diff --git a/hcie-document/src/lib.rs b/hcie-document/src/lib.rs
index b2f365c..59e1b1b 100644
--- a/hcie-document/src/lib.rs
+++ b/hcie-document/src/lib.rs
@@ -88,7 +88,7 @@ impl Document {
     }
 
     pub fn delete_layer(&mut self, idx: usize) {
-        if self.layers.len() <= 1 || idx >= self.layers.len() { return; }
+        if idx >= self.layers.len() { return; }
 
         let layer = &self.layers[idx];
         let action = LayerDeleteAction {
diff --git a/hcie-engine-api/src/ffi.rs b/hcie-engine-api/src/ffi.rs
index 68a0c1b..f80e6f5 100644
--- a/hcie-engine-api/src/ffi.rs
+++ b/hcie-engine-api/src/ffi.rs
@@ -225,7 +225,7 @@ pub unsafe extern "C" fn hcie_engine_flatten_image(handle: *mut EngineHandle) {
 #[no_mangle]
 pub unsafe extern "C" fn hcie_engine_clear_active_layer(handle: *mut EngineHandle) {
     with_engine(handle, |e| {
-        e.clear_active_layer_pixels();
+        e.clear_active_layer_pixels_undoable();
     });
 }
 
diff --git a/hcie-engine-api/src/layer_property_ops.rs b/hcie-engine-api/src/layer_property_ops.rs
index 986fb72..4104665 100644
--- a/hcie-engine-api/src/layer_property_ops.rs
+++ b/hcie-engine-api/src/layer_property_ops.rs
@@ -97,6 +97,11 @@ impl Engine {
         self.below_cache_dirty = true;
     }
 
+    /// Return the index of the currently active layer.
+    pub fn active_layer_index(&self) -> usize {
+        self.document.active_layer
+    }
+
     /// Switch the active (selected) layer by ID.
     pub fn set_active_layer(&mut self, id: u64) {
         if let Some(idx) = self.document.layer_index_by_id(id) {
@@ -270,6 +275,32 @@ impl Engine {
         self.below_cache_dirty = true;
     }
 
+    /// Push a full-layer pixel snapshot for the currently active layer.
+    ///
+    /// **Purpose:** Lets callers that already modified the active layer pixels
+    /// through `set_active_layer_pixels` still record an undo step without
+    /// needing access to the internal `Document` type.
+    ///
+    /// **Arguments:**
+    /// * `before_pixels` — the layer RGBA buffer captured before the change.
+    /// * `layer_idx` — index of the layer to snapshot (typically the active layer).
+    /// * `description` — human-readable history entry label.
+    ///
+    /// **Side Effects:** Appends a `DrawAction` to the document history.
+    pub fn push_active_layer_snapshot(
+        &mut self,
+        before_pixels: Vec<u8>,
+        layer_idx: usize,
+        description: &str,
+    ) {
+        self.document.push_draw_snapshot(
+            layer_idx,
+            before_pixels,
+            None,
+            description.to_string(),
+        );
+    }
+
     pub fn undo(&mut self) -> bool {
         if self.document.can_undo() {
             self.document.undo();
diff --git a/hcie-engine-api/src/lib.rs b/hcie-engine-api/src/lib.rs
index 15a9fb2..86df77e 100644
--- a/hcie-engine-api/src/lib.rs
+++ b/hcie-engine-api/src/lib.rs
@@ -3400,11 +3400,32 @@ impl Engine {
     }
 
     /// Clear pixels only within the active selection mask. If no selection, clears all.
+    /// Records a full-layer draw snapshot so the operation is undoable.
     pub fn clear_selection_pixels(&mut self) {
-        let mask = self.cached_selection_mask.clone();
+        let mask = self.document.selection_mask.clone();
+        let active_idx = self.document.active_layer;
+        log::debug!(
+            "[Engine::clear_selection_pixels] active_layer={}, selection_active={}, document_mask_len={:?}, stroke_cache_mask_len={:?}",
+            active_idx,
+            self.document.selection_active,
+            mask.as_ref().map(Vec::len),
+            self.cached_selection_mask.as_ref().map(Vec::len),
+        );
         if let Some(ref mask_data) = mask {
             let w = self.document.canvas_width as usize;
             let h = self.document.canvas_height as usize;
+            let selected_pixels = mask_data.iter().filter(|coverage| **coverage > 0).count();
+            log::debug!(
+                "[Engine::clear_selection_pixels] clearing selected region: canvas={}x{}, selected_pixels={}",
+                w,
+                h,
+                selected_pixels,
+            );
+            let before_pixels = self
+                .document
+                .active_layer()
+                .map(|layer| layer.pixels.clone())
+                .unwrap_or_default();
             if let Some(layer) = self.document.active_layer_mut() {
                 for y in 0..h {
                     for x in 0..w {
@@ -3418,14 +3439,45 @@ impl Engine {
                     }
                 }
                 layer.dirty = true;
-                self.document.composite_dirty = true;
-                self.document.modified = true;
             }
+            self.document.push_draw_snapshot(
+                active_idx,
+                before_pixels,
+                None,
+                "Clear Selection".to_string(),
+            );
+            self.document.composite_dirty = true;
+            self.document.modified = true;
         } else {
-            self.clear_active_layer_pixels();
+            log::debug!(
+                "[Engine::clear_selection_pixels] no active document mask; clearing the entire active layer"
+            );
+            self.clear_active_layer_pixels_undoable();
         }
     }
 
+    /// Clears the entire active layer and records an undo snapshot.
+    pub fn clear_active_layer_pixels_undoable(&mut self) {
+        let active_idx = self.document.active_layer;
+        let before_pixels = self
+            .document
+            .active_layer()
+            .map(|layer| layer.pixels.clone())
+            .unwrap_or_default();
+        if let Some(layer) = self.document.active_layer_mut() {
+            layer.pixels.fill(0);
+            layer.dirty = true;
+        }
+        self.document.push_draw_snapshot(
+            active_idx,
+            before_pixels,
+            None,
+            "Clear Layer".to_string(),
+        );
+        self.document.composite_dirty = true;
+        self.document.modified = true;
+    }
+
     pub fn set_active_layer_pixels(&mut self, pixels: Vec<u8>) {
         if let Some(layer) = self.document.active_layer_mut() {
             layer.pixels = pixels;
diff --git a/hcie-engine-api/tests/selection_clear.rs b/hcie-engine-api/tests/selection_clear.rs
new file mode 100644
index 0000000..2b53c7b
--- /dev/null
+++ b/hcie-engine-api/tests/selection_clear.rs
@@ -0,0 +1,54 @@
+//! Selection pixel-clearing regression tests.
+//!
+//! **Purpose:** Verifies that destructive selection operations use the active
+//! document selection mask rather than the brush stroke's temporary mask cache.
+//!
+//! **Logic & Workflow:** Each test creates an opaque raster layer through the
+//! public engine API, installs a deterministic selection mask, clears selected
+//! pixels, and compares alpha values inside and outside that mask.
+//!
+//! **Side Effects / Dependencies:** Uses only in-memory `hcie-engine-api` state;
+//! no files, network services, GUI runtime, or engine internals are accessed.
+
+use hcie_engine_api::Engine;
+
+/// Confirms that selection clearing removes internal pixels and preserves all
+/// pixels external to the selection.
+///
+/// **Purpose:** Prevents a regression where `clear_selection_pixels` consulted
+/// an empty stroke cache and consequently cleared the complete active layer.
+///
+/// **Logic & Workflow:** Creates a 3×3 opaque layer, selects only its center
+/// pixel, invokes selection clearing, then checks every resulting alpha value.
+///
+/// **Arguments & Returns:** Takes no arguments and returns nothing; assertion
+/// failures report whether an internal or external pixel was handled wrongly.
+///
+/// **Side Effects / Dependencies:** Mutates only the local in-memory engine and
+/// records the normal undo snapshot generated by the clear operation.
+#[test]
+fn clear_selection_pixels_clears_inside_and_preserves_outside() {
+    let mut engine = Engine::new(3, 3);
+    engine.set_active_layer_pixels(vec![255; 3 * 3 * 4]);
+
+    let mut mask = vec![0; 3 * 3];
+    mask[4] = 255;
+    engine.set_selection_mask(mask);
+
+    engine.clear_selection_pixels();
+
+    let pixels = engine
+        .get_active_layer_pixels()
+        .expect("a new engine must have an active raster layer");
+    for pixel_index in 0..9 {
+        let alpha = pixels[pixel_index * 4 + 3];
+        if pixel_index == 4 {
+            assert_eq!(alpha, 0, "selected center pixel must be cleared");
+        } else {
+            assert_eq!(
+                alpha, 255,
+                "unselected pixel {pixel_index} must be preserved"
+            );
+        }
+    }
+}
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/app.rs b/hcie-iced-app/crates/hcie-iced-gui/src/app.rs
index 187254a..a123c44 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/app.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/app.rs
@@ -12,6 +12,8 @@
 //! These sections are optimized for 4K performance. Modifying them
 //! may cause rendering regressions or performance degradation.
 
+mod transform_dirty;
+
 use crate::ai_chat::{self, AiChatState, ChatMessage, SYSTEM_PROMPT};
 use crate::dialogs;
 use crate::dock::manager::DockDragState;
@@ -22,6 +24,7 @@ use crate::panels;
 use crate::selection;
 use crate::selection::{CropState, SelectionTransform, TransformHandle};
 use crate::theme::ThemeState;
+use self::transform_dirty::preview_bounds;
 use hcie_engine_api::{
     BlendMode, BrushStyle, BrushTip, Engine, FilterType, LayerStyle, Tool, ZOOM_MAX, ZOOM_MIN,
 };
@@ -382,6 +385,12 @@ pub struct IcedDocument {
     pub transform_original: Option<SelectionTransform>,
     /// Source pixels and placement removed when a move transform began, for exact Cancel restore.
     pub transform_source: Option<SelectionTransform>,
+    /// Original active-layer pixels for the transform's single history transaction.
+    pub transform_layer_baseline: Option<Vec<u8>>,
+    /// Original engine selection mask restored when a transform is cancelled.
+    pub transform_selection_baseline: Option<Vec<u8>>,
+    /// Composite snapshot without the floating transform, used as the base for each preview frame.
+    pub transform_preview_base: Option<Vec<u8>>,
     /// Internal clipboard for copy/paste operations
     pub internal_clipboard: Option<SelectionTransform>,
     /// Selection mask (alpha channel) for the current selection
@@ -1053,91 +1062,173 @@ fn is_vector_shape_tool(tool: Tool) -> bool {
     )
 }
 
-/// Composite a floating selection transform's pixels back onto the active layer.
+/// Clears mask-covered alpha values without creating an engine history entry.
 ///
-/// The transform supports translation, uniform scaling (via `size / pixel-dims`),
-/// and rotation (in radians). Each destination pixel is sampled from the
-/// source transform buffer by inverting the affine transform. Source pixels
-/// with zero alpha are skipped so transparent gaps do not overwrite the layer.
+/// **Purpose:** Starts a move transaction while deferring history creation until Apply, avoiding
+/// the engine's standalone `Clear Selection` snapshot used by the Delete command.
 ///
-/// This mirrors egui's `apply_transform_to_layer` but adds rotation support
-/// (egui only handled scale + translation).
+/// **Logic & Workflow:** Visits one mask byte per canvas pixel and clears only the corresponding
+/// layer alpha byte when coverage is non-zero, matching `Engine::clear_selection_pixels`.
+///
+/// **Arguments:** `pixels` is active-layer RGBA data and `mask` is one-byte selection coverage.
+/// **Returns:** Nothing. **Side Effects / Dependencies:** Mutates `pixels`; performs no allocation,
+/// engine call, or history operation.
+fn clear_masked_pixels_without_history(pixels: &mut [u8], mask: &[u8]) {
+    for (index, coverage) in mask.iter().copied().enumerate() {
+        let alpha_index = index * 4 + 3;
+        if coverage > 0 && alpha_index < pixels.len() {
+            pixels[alpha_index] = 0;
+        }
+    }
+}
+
+/// Restores a rectangular region from a stable transform preview baseline.
+///
+/// **Purpose:** Removes the prior floating preview without restoring the full canvas per pointer
+/// event. **Logic & Workflow:** Copies each row in the clipped exclusive rectangle from `source`
+/// to `destination`. **Arguments:** Buffers are full-canvas RGBA data, `canvas_width` is their row
+/// stride, and `bounds` is `[x0, y0, x1, y1]`. **Returns:** Nothing.
+/// **Side Effects / Dependencies:** Mutates only `destination` rows inside `bounds`; no allocation.
+fn restore_preview_region(
+    destination: &mut [u8],
+    source: &[u8],
+    canvas_width: u32,
+    bounds: [u32; 4],
+) {
+    let row_bytes = (bounds[2] - bounds[0]) as usize * 4;
+    for y in bounds[1]..bounds[3] {
+        let start = (y as usize * canvas_width as usize + bounds[0] as usize) * 4;
+        let end = start + row_bytes;
+        if end <= destination.len() && end <= source.len() {
+            destination[start..end].copy_from_slice(&source[start..end]);
+        }
+    }
+}
+
+/// Applies a floating transform and records exactly one caller-labelled layer snapshot.
+///
+/// **Purpose:** Commits move and paste transforms atomically using the same inverse-affine sampler
+/// as preview. **Logic & Workflow:** Reads the current non-preview layer, composites the transform,
+/// installs final pixels, and pushes the supplied original baseline only when pixels changed.
+///
+/// **Arguments:** `engine` is the API boundary, `tr` is floating geometry, canvas dimensions define
+/// raster clipping, `before_pixels` is the transaction baseline, and `history_name` labels undo.
+/// **Returns:** Nothing. **Side Effects / Dependencies:** Mutates the active layer and may append one
+/// engine history snapshot; emits DEBUG timing and transaction-boundary logs.
 fn apply_transform_to_layer(
     engine: &mut hcie_engine_api::Engine,
     tr: &selection::SelectionTransform,
     canvas_w: u32,
     canvas_h: u32,
+    before_pixels: Vec<u8>,
+    history_name: &str,
 ) {
+    let started = std::time::Instant::now();
     if tr.is_empty() || canvas_w == 0 || canvas_h == 0 {
         return;
     }
     let Some(mut dest) = engine.get_active_layer_pixels() else {
         return;
     };
-
-    let src_w = tr.width as f32;
-    let src_h = tr.height as f32;
-    let scale_x = if src_w > 0.0 { tr.size.x / src_w } else { 1.0 };
-    let scale_y = if src_h > 0.0 { tr.size.y / src_h } else { 1.0 };
-    let px = tr.pos.x.round() as f32;
-    let py = tr.pos.y.round() as f32;
-
-    // Destination footprint in canvas pixels.
-    let dst_w = tr.size.x.round().max(1.0) as i32;
-    let dst_h = tr.size.y.round().max(1.0) as i32;
-
-    let cos = tr.rotation.cos();
-    let sin = tr.rotation.sin();
-    let has_rotation = tr.rotation.abs() > 1e-4;
-
-    // Center of the destination box in canvas space.
-    let dst_cx = px + dst_w as f32 / 2.0;
-    let dst_cy = py + dst_h as f32 / 2.0;
-
-    for dy in 0..dst_h {
-        for dx in 0..dst_w {
-            let dst_x = px + dx as f32;
-            let dst_y = py + dy as f32;
-            if dst_x < 0.0 || dst_x >= canvas_w as f32 || dst_y < 0.0 || dst_y >= canvas_h as f32 {
-                continue;
-            }
-
-            // Map destination pixel back into source texture space.
-            let (sx, sy) = if has_rotation {
-                // Vector from dst center, inverse-rotate, then map into src space.
-                let rel_x = dst_x - dst_cx;
-                let rel_y = dst_y - dst_cy;
-                let inv_x = rel_x * cos + rel_y * sin;
-                let inv_y = -rel_x * sin + rel_y * cos;
-                let center_src_x = src_w / 2.0;
-                let center_src_y = src_h / 2.0;
-                (
-                    (inv_x / scale_x + center_src_x),
-                    (inv_y / scale_y + center_src_y),
-                )
-            } else {
-                let nx = dx as f32 / scale_x.max(1e-6);
-                let ny = dy as f32 / scale_y.max(1e-6);
-                (nx, ny)
-            };
-
-            let sxi = sx.round() as i32;
-            let syi = sy.round() as i32;
-            if sxi < 0 || sxi >= tr.width as i32 || syi < 0 || syi >= tr.height as i32 {
-                continue;
-            }
-            let src_idx = (syi as u32 * tr.width + sxi as u32) as usize * 4;
-            if src_idx + 3 >= tr.pixels.len() || tr.pixels[src_idx + 3] == 0 {
-                continue;
-            }
-            let dst_idx = (dst_y as u32 * canvas_w + dst_x as u32) as usize * 4;
-            if dst_idx + 3 < dest.len() {
-                dest[dst_idx..dst_idx + 4].copy_from_slice(&tr.pixels[src_idx..src_idx + 4]);
-            }
-        }
+    let active_idx = engine.active_layer_index();
+    let bounds = selection::transform::composite_transform(&mut dest, canvas_w, canvas_h, tr);
+    log::debug!(
+        "[TransformApply] begin history_name={history_name:?}, active_layer={active_idx}, bounds={bounds:?}"
+    );
+    if before_pixels != dest {
+        engine.set_active_layer_pixels(dest);
+        engine.push_active_layer_snapshot(before_pixels, active_idx, history_name);
     }
+    log::debug!(
+        "[TransformApply] end history_name={history_name:?}, elapsed_us={}",
+        started.elapsed().as_micros()
+    );
+}
 
-    engine.set_active_layer_pixels(dest);
+#[cfg(test)]
+mod transform_transaction_tests {
+    use super::apply_transform_to_layer;
+    use crate::selection::SelectionTransform;
+
+    /// Verifies that move commit creates one correctly named history boundary.
+    ///
+    /// **Purpose:** Prevents reintroduction of a preliminary `Clear Selection` snapshot before the
+    /// final move. **Logic & Workflow:** Starts from a transparent layer, applies one floating pixel
+    /// with an explicit original baseline, and checks history growth and description.
+    /// **Arguments & Returns:** No arguments or return value; assertions report transaction errors.
+    /// **Side Effects / Dependencies:** Uses an in-memory engine only and performs no I/O.
+    #[test]
+    fn move_commit_pushes_one_named_snapshot() {
+        let mut engine = hcie_engine_api::Engine::new(4, 4);
+        let baseline = engine.get_active_layer_pixels().unwrap();
+        let history_before = engine.history_len();
+        let transform = SelectionTransform {
+            pixels: vec![255, 0, 0, 255],
+            width: 1,
+            height: 1,
+            pos: iced::Vector::new(2.0, 1.0),
+            size: iced::Vector::new(1.0, 1.0),
+            rotation: 0.0,
+        };
+
+        apply_transform_to_layer(&mut engine, &transform, 4, 4, baseline, "Move Selection");
+
+        assert_eq!(engine.history_len(), history_before + 1);
+        assert_eq!(
+            engine.history_description(history_before).as_deref(),
+            Some("Move Selection")
+        );
+    }
+}
+
+/// Renders the current floating selection and publishes only its old/new union as dirty.
+///
+/// **Purpose:** Keeps interactive transforms responsive while retaining the protected RefCell
+/// dirty-region accumulator and shader partial-upload path.
+///
+/// **Logic & Workflow:** Restores only the previous transformed AABB from the stable base, invokes
+/// the shared inverse-affine compositor for the current AABB, unions both with any pending dirty
+/// region, and updates the shader Arc in place when uniquely owned. A full-buffer Arc clone is used
+/// only when Iced still owns the prior frame's immutable Arc.
+///
+/// **Arguments:** `doc` contains transform/composite state and `previous_bounds` identifies stale
+/// preview pixels. **Returns:** Nothing. **Side Effects / Dependencies:** Mutates preview buffers,
+/// the dirty-region RefCell, and render generation; logs bounds and elapsed time at DEBUG level.
+fn render_transform_preview(doc: &mut IcedDocument, previous_bounds: Option<[u32; 4]>) {
+    let started = std::time::Instant::now();
+    let canvas_width = doc.engine.canvas_width();
+    let canvas_height = doc.engine.canvas_height();
+    if let (Some(base), Some(bounds)) = (doc.transform_preview_base.as_ref(), previous_bounds) {
+        restore_preview_region(&mut doc.composite_raw, base, canvas_width, bounds);
+    }
+    let current_bounds = doc.selection_transform.as_ref().and_then(|transform| {
+        selection::transform::composite_transform(
+            &mut doc.composite_raw,
+            canvas_width,
+            canvas_height,
+            transform,
+        )
+    });
+    let changed_bounds = match (previous_bounds, current_bounds) {
+        (Some(previous), Some(current)) => Some(union_regions(Some(previous), current)),
+        (Some(bounds), None) | (None, Some(bounds)) => Some(bounds),
+        (None, None) => None,
+    };
+    if let Some(bounds) = changed_bounds {
+        let pending = doc.dirty_region.replace(None);
+        let upload_bounds = union_regions(pending, bounds);
+        doc.dirty_region.replace(Some(upload_bounds));
+        if let Some(shader_pixels) = Arc::get_mut(&mut doc.composite_pixels) {
+            restore_preview_region(shader_pixels, &doc.composite_raw, canvas_width, upload_bounds);
+        } else {
+            doc.composite_pixels = Arc::new(doc.composite_raw.clone());
+        }
+        doc.render_generation = doc.render_generation.wrapping_add(1);
+        log::debug!(
+            "[TransformPreview] previous={previous_bounds:?}, current={current_bounds:?}, upload={upload_bounds:?}, elapsed_us={}",
+            started.elapsed().as_micros()
+        );
+    }
 }
 
 impl HcieIcedApp {
@@ -1206,6 +1297,9 @@ impl HcieIcedApp {
             transform_drag_start: None,
             transform_original: None,
             transform_source: None,
+            transform_layer_baseline: None,
+            transform_selection_baseline: None,
+            transform_preview_base: None,
             internal_clipboard: None,
             selection_mask: None,
             selection_mask_dirty: std::cell::Cell::new(false),
@@ -1242,8 +1336,9 @@ impl HcieIcedApp {
             last_cursor_pos: None,
             canvas_cursor_pos: None,
             active_dialog: ActiveDialog::None,
-            active_tool_slot: 0,
+            active_tool_slot: crate::sidebar::slot_for_tool(hcie_engine_api::Tool::Brush).unwrap_or(0),
             sub_tools_open: false,
+            sidebar_expanded: settings.panel_layout.sidebar_expanded,
             slot_last_used: vec![0; 20],
             dialog_input: String::new(),
             dialog_input2: String::new(),
@@ -1331,7 +1426,6 @@ impl HcieIcedApp {
             vector_drag_session: None,
             bool_shape_a: None,
             bool_shape_b: None,
-            sidebar_expanded: settings.panel_layout.sidebar_expanded,
         };
 
         if let Some(panel) = app
@@ -2267,30 +2361,34 @@ impl HcieIcedApp {
                                     h,
                                 );
                                 if !tr.is_empty() {
-                                    // Clear pixels within the selection area (not the
-                                    // whole layer), then drop the selection mask.
-                                    if let Some(mut layer_pixels) =
-                                        doc.engine.get_active_layer_pixels()
-                                    {
-                                        let cw = w as usize;
-                                        for y in 0..h as usize {
-                                            for x in 0..cw {
-                                                let midx = y * cw + x;
-                                                if midx < mask_data.len() && mask_data[midx] > 0 {
-                                                    let pidx = midx * 4;
-                                                    if pidx + 3 < layer_pixels.len() {
-                                                        layer_pixels[pidx..pidx + 4].fill(0);
-                                                    }
-                                                }
-                                            }
-                                        }
-                                        doc.engine.set_active_layer_pixels(layer_pixels);
-                                    }
+                                    let Some(original_layer) = doc.engine.get_active_layer_pixels()
+                                    else {
+                                        return Task::none();
+                                    };
+                                    let mut cut_layer = original_layer.clone();
+                                    clear_masked_pixels_without_history(&mut cut_layer, &mask_data);
+                                    log::debug!(
+                                        "[TransformMove] begin atomic transaction bounds={:?}, selected_pixels={}",
+                                        preview_bounds(&tr, w, h),
+                                        mask_data.iter().filter(|coverage| **coverage > 0).count()
+                                    );
+                                    doc.engine.set_active_layer_pixels(cut_layer);
                                     doc.engine.selection_clear();
-                                    doc.selection_mask = Some(mask_data);
+                                    doc.selection_mask = Some(mask_data.clone());
                                     doc.selection_mask_dirty.set(true);
                                     doc.transform_source = Some(tr.clone());
+                                    doc.transform_layer_baseline = Some(original_layer);
+                                    doc.transform_selection_baseline = Some(mask_data);
                                     doc.selection_transform = Some(tr);
+                                    doc.transform_drag_handle = TransformHandle::Move;
+                                    doc.transform_drag_start = Some((canvas_x, canvas_y));
+                                    // Force a composite refresh so the cleared source
+                                    // area is visible immediately.
+                                    doc.engine.mark_composite_dirty();
+                                    self.refresh_composite_if_needed();
+                                    let doc = &mut self.documents[self.active_doc];
+                                    doc.transform_preview_base = Some(doc.composite_raw.clone());
+                                    render_transform_preview(doc, None);
                                 }
                             }
                         }
@@ -2964,10 +3062,6 @@ impl HcieIcedApp {
                         // - Style exists → clone and toggle enabled flag
                         let new_style = match existing {
                             None => {
-                                println!(
-                                    "LayerStyleToggle: Style {} not found, creating new",
-                                    disc
-                                );
                                 match disc {
                                     "DropShadow" => LayerStyle::DropShadow {
                                         enabled: true,
@@ -3078,19 +3172,11 @@ impl HcieIcedApp {
                                     | LayerStyle::PatternOverlay { enabled, .. }
                                     | LayerStyle::Stroke { enabled, .. } => {
                                         *enabled = !*enabled;
-                                        println!(
-                                            "LayerStyleToggle: Style {} found, toggling to {}",
-                                            disc, *enabled
-                                        );
                                     }
                                 }
                                 cloned
                             }
                         };
-                        println!(
-                            "LayerStyleToggle: Calling update_layer_style with new_style: {:?}",
-                            new_style
-                        );
                         self.documents[self.active_doc]
                             .engine
                             .update_layer_style(layer_id, new_style);
@@ -4361,7 +4447,7 @@ impl HcieIcedApp {
                     .filter_map(|i| engine.history_description(i).map(|d| (i, d)))
                     .collect();
                 let history_current = engine.history_current();
-                self.documents.push(IcedDocument {
+                let doc = IcedDocument {
                     engine,
                     composite_pixels: Arc::new(composite_raw.clone()),
                     composite_raw,
@@ -4384,12 +4470,15 @@ impl HcieIcedApp {
                     transform_drag_start: None,
                     transform_original: None,
                     transform_source: None,
+                    transform_layer_baseline: None,
+                    transform_selection_baseline: None,
+                    transform_preview_base: None,
                     internal_clipboard: None,
                     selection_mask: None,
                     selection_mask_dirty: std::cell::Cell::new(false),
                     selection_bounds: None,
-            selection_history: Vec::new(),
-            selection_history_marker: 0,
+                    selection_history: Vec::new(),
+                    selection_history_marker: 0,
                     crop_state: CropState::default(),
                     lasso_points: Vec::new(),
                     polygon_points: Vec::new(),
@@ -4405,8 +4494,17 @@ impl HcieIcedApp {
                     selected_vector_shape: None,
                     vector_cycle_index: 0,
                     vector_edit_handle: hcie_engine_api::VectorEditHandle::None,
-                });
-                self.active_doc = self.documents.len() - 1;
+                };
+                if self.show_welcome && self.documents.len() == 1 {
+                    // Replace the placeholder empty document created for the
+                    // welcome screen instead of appending a second tab.
+                    self.documents = vec![doc];
+                    self.active_doc = 0;
+                } else {
+                    self.documents.push(doc);
+                    self.active_doc = self.documents.len() - 1;
+                }
+                self.show_welcome = false;
                 self.active_dialog = ActiveDialog::None;
             }
 
@@ -4673,29 +4771,9 @@ impl HcieIcedApp {
                 doc.quick_mask = !doc.quick_mask;
             }
             Message::ClearPixels => {
-                let mask = self.documents[self.active_doc]
+                self.documents[self.active_doc]
                     .engine
-                    .get_selection_mask()
-                    .map(ToOwned::to_owned);
-                if let (Some(mask), Some(mut pixels)) = (
-                    mask,
-                    self.documents[self.active_doc]
-                        .engine
-                        .get_active_layer_pixels(),
-                ) {
-                    for (index, alpha) in mask.into_iter().enumerate() {
-                        if alpha != 0 && index * 4 + 3 < pixels.len() {
-                            pixels[index * 4..index * 4 + 4].fill(0);
-                        }
-                    }
-                    self.documents[self.active_doc]
-                        .engine
-                        .set_active_layer_pixels(pixels);
-                } else {
-                    self.documents[self.active_doc]
-                        .engine
-                        .clear_active_layer_pixels();
-                }
+                    .clear_selection_pixels();
                 self.documents[self.active_doc].modified = true;
                 self.refresh_composite_if_needed();
             }
@@ -4711,6 +4789,12 @@ impl HcieIcedApp {
             }
             Message::TransformDragMove(x, y) => {
                 let doc = &mut self.documents[self.active_doc];
+                let canvas_w = doc.engine.canvas_width();
+                let canvas_h = doc.engine.canvas_height();
+                let previous_preview_bounds = doc
+                    .selection_transform
+                    .as_ref()
+                    .and_then(|tr| preview_bounds(tr, canvas_w, canvas_h));
                 if let (Some(start), Some(ref mut tr)) =
                     (doc.transform_drag_start, &mut doc.selection_transform)
                 {
@@ -4722,54 +4806,33 @@ impl HcieIcedApp {
                             tr.pos = iced::Vector::new(tr.pos.x + dx, tr.pos.y + dy);
                             doc.transform_drag_start = Some((x, y));
                         }
-                        TransformHandle::TopLeft => {
-                            tr.pos = iced::Vector::new(tr.pos.x + dx, tr.pos.y + dy);
-                            tr.size = iced::Vector::new(tr.size.x - dx, tr.size.y - dy);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::TopRight => {
-                            tr.size = iced::Vector::new(tr.size.x + dx, tr.size.y - dy);
-                            tr.pos = iced::Vector::new(tr.pos.x, tr.pos.y + dy);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::BottomLeft => {
-                            tr.size = iced::Vector::new(tr.size.x - dx, tr.size.y + dy);
-                            tr.pos = iced::Vector::new(tr.pos.x + dx, tr.pos.y);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::BottomRight => {
-                            tr.size = iced::Vector::new(tr.size.x + dx, tr.size.y + dy);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::Top => {
-                            tr.pos = iced::Vector::new(tr.pos.x, tr.pos.y + dy);
-                            tr.size = iced::Vector::new(tr.size.x, tr.size.y - dy);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::Bottom => {
-                            tr.size = iced::Vector::new(tr.size.x, tr.size.y + dy);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::Left => {
-                            tr.pos = iced::Vector::new(tr.pos.x + dx, tr.pos.y);
-                            tr.size = iced::Vector::new(tr.size.x - dx, tr.size.y);
-                            doc.transform_drag_start = Some((x, y));
-                        }
-                        TransformHandle::Right => {
-                            tr.size = iced::Vector::new(tr.size.x + dx, tr.size.y);
+                        TransformHandle::TopLeft
+                        | TransformHandle::TopRight
+                        | TransformHandle::BottomLeft
+                        | TransformHandle::BottomRight
+                        | TransformHandle::Top
+                        | TransformHandle::Bottom
+                        | TransformHandle::Left
+                        | TransformHandle::Right => {
+                            tr.resize_from_delta(doc.transform_drag_handle, dx, dy);
                             doc.transform_drag_start = Some((x, y));
                         }
                         TransformHandle::Rotate => {
-                            // Calculate rotation from center
-                            let center_x = tr.pos.x + tr.size.x / 2.0;
-                            let center_y = tr.pos.y + tr.size.y / 2.0;
-                            let angle = (y - center_y).atan2(x - center_x);
-                            tr.rotation = angle;
+                            if let Some(original) = doc.transform_original.as_ref() {
+                                tr.rotation = selection::transform::rotation_from_drag(
+                                    original,
+                                    start,
+                                    (x, y),
+                                );
+                            }
                         }
                         TransformHandle::None => {}
                     }
                     tr.sanitize_geometry(self.modifiers.shift());
                 }
+                let doc = &mut self.documents[self.active_doc];
+                render_transform_preview(doc, previous_preview_bounds);
+                return Task::perform(async {}, |_| Message::CompositeRefresh);
             }
             Message::TransformDragEnd => {
                 let doc = &mut self.documents[self.active_doc];
@@ -4779,39 +4842,70 @@ impl HcieIcedApp {
             Message::TransformApply => {
                 let tr_taken = self.documents[self.active_doc].selection_transform.take();
                 if let Some(tr) = tr_taken {
-                    let canvas_w = self.documents[self.active_doc].engine.canvas_width();
-                    let canvas_h = self.documents[self.active_doc].engine.canvas_height();
+                    let doc = &mut self.documents[self.active_doc];
+                    let canvas_w = doc.engine.canvas_width();
+                    let canvas_h = doc.engine.canvas_height();
+                    let was_move = doc.transform_source.is_some();
+                    let before_pixels = doc
+                        .transform_layer_baseline
+                        .take()
+                        .or_else(|| doc.engine.get_active_layer_pixels());
+                    let Some(before_pixels) = before_pixels else {
+                        return Task::none();
+                    };
                     apply_transform_to_layer(
-                        &mut self.documents[self.active_doc].engine,
+                        &mut doc.engine,
                         &tr,
                         canvas_w,
                         canvas_h,
+                        before_pixels,
+                        if was_move {
+                            "Move Selection"
+                        } else {
+                            "Transform Apply"
+                        },
                     );
-                    self.documents[self.active_doc].engine.selection_clear();
-                    self.documents[self.active_doc].selection_bounds = None;
-                    self.documents[self.active_doc].selection_mask = None;
-                    self.documents[self.active_doc].selection_mask_dirty.set(true);
-                    self.documents[self.active_doc].transform_drag_handle = TransformHandle::None;
-                    self.documents[self.active_doc].transform_drag_start = None;
-                    self.documents[self.active_doc].transform_original = None;
-                    self.documents[self.active_doc].transform_source = None;
-                    self.documents[self.active_doc].modified = true;
+                    doc.engine.selection_clear();
+                    doc.selection_bounds = None;
+                    doc.selection_mask = None;
+                    doc.selection_mask_dirty.set(true);
+                    doc.transform_drag_handle = TransformHandle::None;
+                    doc.transform_drag_start = None;
+                    doc.transform_original = None;
+                    doc.transform_source = None;
+                    doc.transform_selection_baseline = None;
+                    doc.transform_preview_base = None;
+                    doc.modified = true;
                     self.refresh_composite_if_needed();
                     return Task::perform(async {}, |_| Message::CompositeRefresh);
                 }
             }
             Message::TransformCancel => {
                 let doc = &mut self.documents[self.active_doc];
-                if let Some(source) = doc.transform_source.take() {
-                    let width = doc.engine.canvas_width();
-                    let height = doc.engine.canvas_height();
-                    apply_transform_to_layer(&mut doc.engine, &source, width, height);
+                log::debug!(
+                    "[TransformCancel] begin restore_layer={}, restore_selection={}",
+                    doc.transform_source.is_some() && doc.transform_layer_baseline.is_some(),
+                    doc.transform_selection_baseline.is_some()
+                );
+                let original_layer = doc.transform_layer_baseline.take();
+                if doc.transform_source.is_some() {
+                    if let Some(original_layer) = original_layer {
+                        doc.engine.set_active_layer_pixels(original_layer);
+                    }
+                }
+                if let Some(mask) = doc.transform_selection_baseline.take() {
+                    doc.engine.set_selection_mask(mask.clone());
+                    doc.selection_mask = Some(mask);
+                    doc.selection_mask_dirty.set(true);
                 }
                 doc.selection_transform = None;
+                doc.transform_source = None;
                 doc.transform_original = None;
                 doc.transform_drag_start = None;
                 doc.transform_drag_handle = TransformHandle::None;
+                doc.transform_preview_base = None;
                 self.refresh_composite_if_needed();
+                log::debug!("[TransformCancel] end without history snapshot");
             }
 
             // ── Vector tools ──────────────────────────────
@@ -6204,30 +6298,31 @@ impl HcieIcedApp {
                             transform.height,
                         );
                         doc.internal_clipboard = Some(transform);
-                        if let Some(mut pixels) = doc.engine.get_active_layer_pixels() {
-                            for (index, alpha) in mask.into_iter().enumerate() {
-                                if alpha != 0 && index * 4 + 3 < pixels.len() {
-                                    pixels[index * 4..index * 4 + 4].fill(0);
-                                }
-                            }
-                            doc.engine.set_active_layer_pixels(pixels);
-                            doc.modified = true;
-                        }
+                        // Record an undoable snapshot of the source pixels before
+                        // clearing them, then clear the selected region via the engine.
+                        doc.engine.clear_selection_pixels();
+                        doc.modified = true;
                     }
                 }
                 self.refresh_composite_if_needed();
             }
             Message::PasteImage => {
-                let doc = &self.documents[self.active_doc];
-
                 // Check internal clipboard first
-                if let Some(ref transform) = doc.internal_clipboard {
+                if let Some(transform) = self.documents[self.active_doc].internal_clipboard.clone()
+                {
                     // Enter transform mode with the clipboard content
-                    let mut placed = transform.clone();
+                    let mut placed = transform;
                     placed.pos.x += 10.0;
                     placed.pos.y += 10.0;
-                    self.documents[self.active_doc].selection_transform = Some(placed);
-                    self.documents[self.active_doc].transform_drag_handle = TransformHandle::None;
+                    let doc = &mut self.documents[self.active_doc];
+                    doc.transform_layer_baseline = doc.engine.get_active_layer_pixels();
+                    doc.transform_selection_baseline =
+                        doc.engine.get_selection_mask().map(ToOwned::to_owned);
+                    doc.transform_source = None;
+                    doc.transform_preview_base = Some(doc.composite_raw.clone());
+                    doc.selection_transform = Some(placed);
+                    doc.transform_drag_handle = TransformHandle::None;
+                    render_transform_preview(doc, None);
                     return Task::perform(async {}, |_| Message::CompositeRefresh);
                 }
 
@@ -6270,10 +6365,17 @@ impl HcieIcedApp {
             }
             Message::ImagePasted(Ok(Some((pixels, w, h)))) => {
                 log::info!("Pasted image: {}x{}", w, h);
-                let canvas_w = self.documents[self.active_doc].engine.canvas_width();
-                let canvas_h = self.documents[self.active_doc].engine.canvas_height();
-                self.documents[self.active_doc].selection_transform =
+                let doc = &mut self.documents[self.active_doc];
+                let canvas_w = doc.engine.canvas_width();
+                let canvas_h = doc.engine.canvas_height();
+                doc.transform_layer_baseline = doc.engine.get_active_layer_pixels();
+                doc.transform_selection_baseline =
+                    doc.engine.get_selection_mask().map(ToOwned::to_owned);
+                doc.transform_source = None;
+                doc.transform_preview_base = Some(doc.composite_raw.clone());
+                doc.selection_transform =
                     selection::clipboard::centered_transform(pixels, w, h, canvas_w, canvas_h);
+                render_transform_preview(doc, None);
             }
             Message::ImagePasted(Ok(None)) => {
                 log::info!("No image in clipboard");
@@ -6761,6 +6863,9 @@ impl HcieIcedApp {
                     transform_drag_start: None,
                     transform_original: None,
                     transform_source: None,
+                    transform_layer_baseline: None,
+                    transform_selection_baseline: None,
+                    transform_preview_base: None,
                     internal_clipboard: None,
                     selection_mask: None,
                     selection_mask_dirty: std::cell::Cell::new(false),
@@ -7446,6 +7551,7 @@ impl HcieIcedApp {
         );
 
         // Toolbox — 36px strip (single column) or 72px (2 columns) on the left edge
+        log::info!("[view] sidebar_expanded={}", self.sidebar_expanded);
         let toolbox = crate::sidebar::view(
             &self.tool_state,
             &self.fg_color,
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/app/transform_dirty.rs b/hcie-iced-app/crates/hcie-iced-gui/src/app/transform_dirty.rs
new file mode 100644
index 0000000..a0e61ce
--- /dev/null
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/app/transform_dirty.rs
@@ -0,0 +1,86 @@
+//! Selection-transform preview invalidation utilities.
+//!
+//! **Purpose:** Computes canvas-clipped dirty bounds for floating selection
+//! previews so both their previous and current positions can be uploaded to the
+//! persistent GPU texture during interactive movement.
+//!
+//! **Logic & Workflow:** Preview geometry is rounded exactly like the CPU
+//! compositor, clamped to the canvas origin, and clipped at the right and
+//! bottom canvas edges. Empty or fully out-of-canvas rectangles return `None`.
+//!
+//! **Side Effects / Dependencies:** The module is deterministic and has no I/O,
+//! global state, allocation, engine dependency, or GPU dependency.
+
+/// Calculates the clipped pixel bounds occupied by a transform preview.
+///
+/// **Purpose:** Produces the dirty rectangle that must be restored or redrawn
+/// when a floating selection changes position or dimensions.
+///
+/// **Logic & Workflow:** Delegates to the shared rotated-corner AABB calculation
+/// used by both preview and apply, clips it to the canvas, and rejects empty rectangles.
+///
+/// **Arguments:**
+/// - `transform`: Floating selection source and affine geometry.
+/// - `canvas_width`, `canvas_height`: Clipping dimensions of the document.
+///
+/// **Returns:** `Some([x0, y0, x1, y1])` for a non-empty clipped rectangle, or
+/// `None` when the preview cannot affect the canvas.
+///
+/// **Side Effects / Dependencies:** None.
+pub(crate) fn preview_bounds(
+    transform: &crate::selection::SelectionTransform,
+    canvas_width: u32,
+    canvas_height: u32,
+) -> Option<[u32; 4]> {
+    crate::selection::transform::transformed_bounds(transform, canvas_width, canvas_height)
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::selection::SelectionTransform;
+    use iced::Vector;
+
+    use super::preview_bounds;
+
+    fn transform(x: f32, y: f32) -> SelectionTransform {
+        SelectionTransform {
+            pixels: vec![255; 30 * 40 * 4],
+            width: 30,
+            height: 40,
+            pos: Vector::new(x, y),
+            size: Vector::new(30.0, 40.0),
+            rotation: 0.0,
+        }
+    }
+
+    /// Verifies that consecutive preview positions expose both the old and new
+    /// rectangles needed by the caller's dirty-region union.
+    ///
+    /// **Purpose:** Guards against stale GPU pixels remaining at an old drag
+    /// position when only the current preview rectangle is uploaded.
+    ///
+    /// **Logic & Workflow:** Computes two partially overlapping positions and
+    /// confirms their bounds preserve the complete restoration/redraw extent.
+    ///
+    /// **Arguments & Returns:** Takes no arguments and returns nothing;
+    /// assertion failures identify incorrect transform bounds.
+    ///
+    /// **Side Effects / Dependencies:** None.
+    #[test]
+    fn consecutive_positions_retain_old_and_new_extents() {
+        let previous = preview_bounds(&transform(10.0, 20.0), 100, 100).unwrap();
+        let current = preview_bounds(&transform(25.0, 30.0), 100, 100).unwrap();
+
+        assert_eq!(previous, [10, 20, 40, 60]);
+        assert_eq!(current, [25, 30, 55, 70]);
+        assert_eq!(
+            [
+                previous[0].min(current[0]),
+                previous[1].min(current[1]),
+                previous[2].max(current[2]),
+                previous[3].max(current[3]),
+            ],
+            [10, 20, 55, 70],
+        );
+    }
+}
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/canvas/mod.rs b/hcie-iced-app/crates/hcie-iced-gui/src/canvas/mod.rs
index 0c1e9fa..e1cb666 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/canvas/mod.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/canvas/mod.rs
@@ -167,7 +167,12 @@ impl OverlayProgram {
     }
 
     /// Test which transform handle is at the given viewport position.
-    pub fn hit_test_handle(&self, viewport_x: f32, viewport_y: f32) -> TransformHandle {
+    pub fn hit_test_handle(
+        &self,
+        viewport_x: f32,
+        viewport_y: f32,
+        pane_size: Size,
+    ) -> TransformHandle {
         let Some(ref tr) = self.selection_transform else {
             return TransformHandle::None;
         };
@@ -175,54 +180,13 @@ impl OverlayProgram {
             return TransformHandle::None;
         }
 
-        let (origin_x, origin_y, _, _) = self.canvas_origin(iced::Size::new(0.0, 0.0));
+        let (origin_x, origin_y, _, _) = self.canvas_origin(pane_size);
 
         // Convert viewport to canvas coordinates
         let canvas_x = (viewport_x - origin_x) / self.zoom;
         let canvas_y = (viewport_y - origin_y) / self.zoom;
 
-        let handle_size = TransformHandle::HANDLE_SIZE / self.zoom;
-        let half = handle_size / 2.0;
-
-        let x = tr.pos.x;
-        let y = tr.pos.y;
-        let w = tr.size.x;
-        let h = tr.size.y;
-
-        // Check rotation handle first (it's outside the box)
-        let rotate_y = y - TransformHandle::ROTATE_OFFSET / self.zoom;
-        let rotate_x = x + w / 2.0;
-        let rotate_radius = 4.0 / self.zoom;
-        let dx = canvas_x - rotate_x;
-        let dy = canvas_y - rotate_y;
-        if dx * dx + dy * dy <= rotate_radius * rotate_radius {
-            return TransformHandle::Rotate;
-        }
-
-        // Check corner and edge handles
-        let handles = [
-            (TransformHandle::TopLeft, x, y),
-            (TransformHandle::TopRight, x + w, y),
-            (TransformHandle::BottomLeft, x, y + h),
-            (TransformHandle::BottomRight, x + w, y + h),
-            (TransformHandle::Top, x + w / 2.0, y),
-            (TransformHandle::Bottom, x + w / 2.0, y + h),
-            (TransformHandle::Left, x, y + h / 2.0),
-            (TransformHandle::Right, x + w, y + h / 2.0),
-        ];
-
-        for (handle, hx, hy) in &handles {
-            if (canvas_x - hx).abs() <= half && (canvas_y - hy).abs() <= half {
-                return *handle;
-            }
-        }
-
-        // Check if inside the selection box (for move)
-        if canvas_x >= x && canvas_x <= x + w && canvas_y >= y && canvas_y <= y + h {
-            return TransformHandle::Move;
-        }
-
-        TransformHandle::None
+        tr.hit_test(canvas_x, canvas_y, self.zoom)
     }
 
     /// Draw transform handles for selection.
@@ -233,25 +197,17 @@ impl OverlayProgram {
         origin_x: f32,
         origin_y: f32,
     ) {
-        let handle_size = TransformHandle::HANDLE_SIZE / self.zoom.max(1.0);
+        let handle_size = TransformHandle::HANDLE_SIZE;
         let half = handle_size / 2.0;
 
-        // Calculate handle positions in viewport coordinates
-        let x = origin_x + tr.pos.x * self.zoom;
-        let y = origin_y + tr.pos.y * self.zoom;
-        let w = tr.size.x * self.zoom;
-        let h = tr.size.y * self.zoom;
-
-        let handles = [
-            (TransformHandle::TopLeft, x, y),
-            (TransformHandle::TopRight, x + w, y),
-            (TransformHandle::BottomLeft, x, y + h),
-            (TransformHandle::BottomRight, x + w, y + h),
-            (TransformHandle::Top, x + w / 2.0, y),
-            (TransformHandle::Bottom, x + w / 2.0, y + h),
-            (TransformHandle::Left, x, y + h / 2.0),
-            (TransformHandle::Right, x + w, y + h / 2.0),
-        ];
+        let handles = TransformHandle::RESIZE_HANDLES.map(|handle| {
+            let (canvas_x, canvas_y) = tr.handle_position(handle, self.zoom);
+            (
+                handle,
+                origin_x + canvas_x * self.zoom,
+                origin_y + canvas_y * self.zoom,
+            )
+        });
 
         let handle_color = iced::Color::from_rgb(1.0, 1.0, 1.0);
         let handle_stroke_color = iced::Color::from_rgb(0.0, 0.0, 0.0);
@@ -268,29 +224,38 @@ impl OverlayProgram {
                 &rect,
                 Stroke {
                     style: canvas::stroke::Style::Solid(handle_stroke_color),
-                    width: 1.0 / self.zoom.max(1.0),
+                    width: 1.0,
                     ..Default::default()
                 },
             );
         }
 
         // Draw rotation handle (circle above top center)
-        let rotate_y = y - TransformHandle::ROTATE_OFFSET / self.zoom.max(1.0);
-        let rotate_x = x + w / 2.0;
-        let rotate_radius = 4.0 / self.zoom.max(1.0);
+        let (rotate_canvas_x, rotate_canvas_y) =
+            tr.handle_position(TransformHandle::Rotate, self.zoom);
+        let rotate_y = origin_y + rotate_canvas_y * self.zoom;
+        let rotate_x = origin_x + rotate_canvas_x * self.zoom;
+        let rotate_radius = 4.0;
         let rotate_circle = Path::circle(Point::new(rotate_x, rotate_y), rotate_radius);
         frame.fill(&rotate_circle, handle_color);
         frame.stroke(
             &rotate_circle,
             Stroke {
                 style: canvas::stroke::Style::Solid(handle_stroke_color),
-                width: 1.0 / self.zoom.max(1.0),
+                width: 1.0,
                 ..Default::default()
             },
         );
 
         // Draw line from top center to rotation handle
-        let line = Path::line(Point::new(x + w / 2.0, y), Point::new(rotate_x, rotate_y));
+        let (top_canvas_x, top_canvas_y) = tr.handle_position(TransformHandle::Top, self.zoom);
+        let line = Path::line(
+            Point::new(
+                origin_x + top_canvas_x * self.zoom,
+                origin_y + top_canvas_y * self.zoom,
+            ),
+            Point::new(rotate_x, rotate_y),
+        );
         frame.stroke(
             &line,
             Stroke {
@@ -1169,11 +1134,25 @@ impl canvas::Program<Message> for OverlayProgram {
             if let Some(ref tr) = self.selection_transform {
                 if !tr.is_empty() {
                     // Draw dotted bounding box
-                    let x = origin_x + tr.pos.x * self.zoom;
-                    let y = origin_y + tr.pos.y * self.zoom;
-                    let w = tr.size.x * self.zoom;
-                    let h = tr.size.y * self.zoom;
-                    let bbox = Path::rectangle(Point::new(x, y), Size::new(w, h));
+                    let corners = [
+                        tr.handle_position(TransformHandle::TopLeft, self.zoom),
+                        tr.handle_position(TransformHandle::TopRight, self.zoom),
+                        tr.handle_position(TransformHandle::BottomRight, self.zoom),
+                        tr.handle_position(TransformHandle::BottomLeft, self.zoom),
+                    ];
+                    let bbox = Path::new(|builder| {
+                        builder.move_to(Point::new(
+                            origin_x + corners[0].0 * self.zoom,
+                            origin_y + corners[0].1 * self.zoom,
+                        ));
+                        for corner in &corners[1..] {
+                            builder.line_to(Point::new(
+                                origin_x + corner.0 * self.zoom,
+                                origin_y + corner.1 * self.zoom,
+                            ));
+                        }
+                        builder.close();
+                    });
                     frame.stroke(
                         &bbox,
                         Stroke {
@@ -1301,7 +1280,8 @@ impl canvas::Program<Message> for OverlayProgram {
 
                 // Update hovered handle
                 if self.selection_transform.is_some() {
-                    state.hovered_handle = self.hit_test_handle(position.x, position.y);
+                    state.hovered_handle =
+                        self.hit_test_handle(local_pos.x, local_pos.y, bounds.size());
                 } else {
                     state.hovered_handle = TransformHandle::None;
                 }
@@ -1349,6 +1329,23 @@ impl canvas::Program<Message> for OverlayProgram {
         if !cursor.is_over(bounds) {
             return mouse::Interaction::default();
         }
+        match state.hovered_handle {
+            TransformHandle::Move => return mouse::Interaction::Grab,
+            TransformHandle::Top | TransformHandle::Bottom => {
+                return mouse::Interaction::ResizingVertically
+            }
+            TransformHandle::Left | TransformHandle::Right => {
+                return mouse::Interaction::ResizingHorizontally
+            }
+            TransformHandle::TopLeft | TransformHandle::BottomRight => {
+                return mouse::Interaction::ResizingDiagonallyDown
+            }
+            TransformHandle::TopRight | TransformHandle::BottomLeft => {
+                return mouse::Interaction::ResizingDiagonallyUp
+            }
+            TransformHandle::Rotate => return mouse::Interaction::Pointer,
+            TransformHandle::None => {}
+        }
         match state.hovered_vector_handle {
             H::Move => mouse::Interaction::Grab,
             H::Top | H::Bottom => mouse::Interaction::ResizingVertically,
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/panels/menus.rs b/hcie-iced-app/crates/hcie-iced-gui/src/panels/menus.rs
index ae7648c..cc6923e 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/panels/menus.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/panels/menus.rs
@@ -10,12 +10,13 @@
 //! - Hover: #b3d9ff (light blue)
 //! - Shortcuts: #666666 (gray, right-aligned)
 //! - Separators: 1px #cccccc lines
-//! - Sub-menus: indicated by ">" arrow on the right
+//! - Sub-menus: indicated by a readable `›` arrow in a stable right gutter
 
 use crate::app::Message;
 use crate::dock::state::{DockState, PaneType};
+use crate::panels::typography;
 use crate::theme::ThemeColors;
-use iced::widget::{column, container, horizontal_rule, mouse_area, row, text};
+use iced::widget::{column, container, horizontal_rule, mouse_area, row, text, Space};
 use iced::{Element, Length};
 
 /// Identifies one implemented menu operation independently of menu position or label.
@@ -157,6 +158,74 @@ impl MenuItem {
     }
 }
 
+/// Builds one aligned dropdown or context-menu row with stable semantic gutters.
+///
+/// **Purpose:** Gives every menu entry identical label alignment regardless of whether it is
+/// checked, has a shortcut, or opens a submenu.
+/// **Logic & Workflow:** The helper reserves fixed-width leading checkmark, trailing shortcut,
+/// and trailing arrow columns around a fill-width label, then vertically centers all content in
+/// the shared compact row height. Empty text and space widgets retain the unused column widths.
+/// **Arguments:** `item` supplies owned display strings, `is_checked` selects the checkmark, and
+/// `colors` supplies theme-aware foreground colors.
+/// **Returns:** A message-compatible row element with no interaction of its own.
+/// **Side Effects / Dependencies:** None; callers wrap the row in the existing command button.
+fn menu_item_row(
+    item: &MenuItem,
+    is_checked: bool,
+    colors: ThemeColors,
+) -> Element<'static, Message> {
+    let checkmark: Element<'static, Message> = if is_checked {
+        container(
+            text("✓")
+                .size(typography::MENU_LABEL)
+                .color(iced::Color::from_rgba(0.2, 0.6, 0.2, 1.0)),
+        )
+        .width(typography::MENU_CHECK_GUTTER)
+        .align_x(iced::alignment::Horizontal::Center)
+        .into()
+    } else {
+        Space::with_width(typography::MENU_CHECK_GUTTER).into()
+    };
+
+    let shortcut = container(
+        text(item.shortcut.clone())
+            .size(typography::MENU_SHORTCUT)
+            .color(colors.menu_shortcut),
+    )
+    .width(typography::MENU_SHORTCUT_GUTTER)
+    .align_x(iced::alignment::Horizontal::Right);
+
+    let submenu_arrow = container(
+        text(if item.has_submenu {
+            typography::MENU_SUBMENU_ARROW
+        } else {
+            ""
+        })
+        .size(typography::MENU_SHORTCUT)
+        .color(colors.menu_shortcut),
+    )
+    .width(typography::MENU_ARROW_GUTTER)
+    .align_x(iced::alignment::Horizontal::Right);
+
+    row![
+        checkmark,
+        text(item.label.clone())
+            .size(typography::MENU_LABEL)
+            .color(if item.enabled {
+                colors.menu_text
+            } else {
+                colors.menu_shortcut
+            })
+            .width(Length::Fill),
+        shortcut,
+        submenu_arrow,
+    ]
+    .spacing(0)
+    .align_y(iced::Alignment::Center)
+    .height(Length::Fill)
+    .into()
+}
+
 /// All menu definitions matching Photopea's menu structure exactly.
 #[derive(Clone)]
 struct MenuDef {
@@ -539,19 +608,11 @@ pub fn dropdown_overlay(
             items.push(
                 container(horizontal_rule(1))
                     .width(Length::Fill)
-                    .padding([2, 8])
+                    .padding([2, typography::MENU_ROW_HORIZONTAL_PADDING])
                     .into(),
             );
         } else {
-            let lbl = item.label.clone();
-            let sht = item.shortcut.clone();
-            let has_sub = item.has_submenu;
             let enabled = item.enabled;
-            let label_color = if enabled {
-                colors.menu_text
-            } else {
-                colors.menu_shortcut
-            };
 
             // Check if this is a Window menu item that should show a checkmark
             let is_window_panel = menu_idx == 7 && item_idx <= 10;
@@ -577,46 +638,7 @@ pub fn dropdown_overlay(
                 false
             };
 
-            // Photopea-style: label left, shortcut right in gray, submenu arrow ">" if needed
-            // Add checkmark prefix for open panels in Window menu
-            let label_row: Element<'static, Message> = {
-                let mut row_items = vec![];
-                if is_checked {
-                    row_items.push(
-                        text("✓ ")
-                            .size(13)
-                            .color(iced::Color::from_rgba(0.2, 0.6, 0.2, 1.0))
-                            .into(),
-                    );
-                }
-                row_items.push(
-                    text(lbl)
-                        .size(13)
-                        .font(iced::Font {
-                            weight: iced::font::Weight::Semibold,
-                            ..iced::Font::default()
-                        })
-                        .color(label_color)
-                        .width(Length::Fill)
-                        .into(),
-                );
-                if !sht.is_empty() {
-                    row_items.push(
-                        text(sht)
-                            .size(12)
-                            .font(iced::Font {
-                                weight: iced::font::Weight::Medium,
-                                ..iced::Font::default()
-                            })
-                            .color(colors.menu_shortcut)
-                            .into(),
-                    );
-                }
-                if has_sub {
-                    row_items.push(text(">").size(12).color(colors.menu_shortcut).into());
-                }
-                row(row_items).spacing(16).into()
-            };
+            let label_row = menu_item_row(item, is_checked, colors);
 
             let c = colors;
 
@@ -625,37 +647,46 @@ pub fn dropdown_overlay(
                     .command
                     .clone()
                     .expect("enabled menu leaves must have commands");
-                let btn =
-                    iced::widget::button(container(label_row).width(Length::Fill).padding([6, 16]))
-                        .on_press(Message::MenuCommand(command))
-                        .padding(0)
-                        .style(
-                            move |_theme: &iced::Theme, status: iced::widget::button::Status| {
-                                match status {
-                                    // Photopea-style hover: light blue highlight
-                                    iced::widget::button::Status::Hovered => {
-                                        iced::widget::button::Style {
-                                            background: Some(iced::Background::Color(c.menu_hover)),
-                                            text_color: c.menu_text,
-                                            border: iced::Border::default(),
-                                            ..Default::default()
-                                        }
-                                    }
-                                    _ => iced::widget::button::Style {
-                                        background: Some(iced::Background::Color(c.menu_bg)),
-                                        text_color: c.menu_text,
-                                        border: iced::Border::default(),
-                                        ..Default::default()
-                                    },
-                                }
+                let btn = iced::widget::button(
+                    container(label_row)
+                        .width(Length::Fill)
+                        .height(typography::MENU_ROW_HEIGHT)
+                        .padding([
+                            typography::MENU_ROW_VERTICAL_PADDING,
+                            typography::MENU_ROW_HORIZONTAL_PADDING,
+                        ]),
+                )
+                .on_press(Message::MenuCommand(command))
+                .padding(0)
+                .style(
+                    move |_theme: &iced::Theme, status: iced::widget::button::Status| {
+                        match status {
+                            // Photopea-style hover: light blue highlight
+                            iced::widget::button::Status::Hovered => iced::widget::button::Style {
+                                background: Some(iced::Background::Color(c.menu_hover)),
+                                text_color: c.menu_text,
+                                border: iced::Border::default(),
+                                ..Default::default()
                             },
-                        );
+                            _ => iced::widget::button::Style {
+                                background: Some(iced::Background::Color(c.menu_bg)),
+                                text_color: c.menu_text,
+                                border: iced::Border::default(),
+                                ..Default::default()
+                            },
+                        }
+                    },
+                );
                 items.push(btn.into());
             } else {
                 // Photopea-style disabled: lighter text
                 let disabled_item = container(label_row)
                     .width(Length::Fill)
-                    .padding([6, 16])
+                    .height(typography::MENU_ROW_HEIGHT)
+                    .padding([
+                        typography::MENU_ROW_VERTICAL_PADDING,
+                        typography::MENU_ROW_HORIZONTAL_PADDING,
+                    ])
                     .style(move |_theme| iced::widget::container::Style {
                         background: Some(iced::Background::Color(colors.menu_bg)),
                         text_color: Some(colors.menu_shortcut),
@@ -762,54 +793,39 @@ pub fn canvas_context_menu<'a>(
                         fill_mode: iced::widget::rule::FillMode::Full,
                     }),
                 )
-                .padding([4, 0])
+                .padding([4, typography::MENU_ROW_HORIZONTAL_PADDING])
                 .into(),
             );
         } else {
-            let label = text(item.label.clone())
-                .size(13)
-                .font(iced::Font {
-                    weight: iced::font::Weight::Semibold,
-                    ..iced::Font::default()
-                })
-                .style(move |_theme| iced::widget::text::Style {
-                    color: Some(colors.menu_text),
-                });
-            let mut label_row = row![label].align_y(iced::Alignment::Center);
-
-            if !item.shortcut.is_empty() {
-                label_row = label_row.push(iced::widget::Space::with_width(Length::Fill));
-                label_row = label_row.push(text(item.shortcut).size(12).style(move |_theme| {
-                    iced::widget::text::Style {
-                        color: Some(colors.menu_shortcut),
-                    }
-                }));
-            }
+            let label_row = menu_item_row(&item, false, colors);
 
             let c = colors;
-            let menu_item =
-                iced::widget::button(container(label_row).width(Length::Fill).padding([7, 16]))
-                    .padding(0)
-                    .style(
-                        move |_theme: &iced::Theme, status: iced::widget::button::Status| {
-                            match status {
-                                iced::widget::button::Status::Hovered => {
-                                    iced::widget::button::Style {
-                                        background: Some(iced::Background::Color(c.menu_hover)),
-                                        text_color: c.menu_text,
-                                        border: iced::Border::default(),
-                                        ..Default::default()
-                                    }
-                                }
-                                _ => iced::widget::button::Style {
-                                    background: Some(iced::Background::Color(c.menu_bg)),
-                                    text_color: c.menu_text,
-                                    border: iced::Border::default(),
-                                    ..Default::default()
-                                },
-                            }
-                        },
-                    );
+            let menu_item = iced::widget::button(
+                container(label_row)
+                    .width(Length::Fill)
+                    .height(typography::MENU_ROW_HEIGHT)
+                    .padding([
+                        typography::MENU_ROW_VERTICAL_PADDING,
+                        typography::MENU_ROW_HORIZONTAL_PADDING,
+                    ]),
+            )
+            .padding(0)
+            .style(
+                move |_theme: &iced::Theme, status: iced::widget::button::Status| match status {
+                    iced::widget::button::Status::Hovered => iced::widget::button::Style {
+                        background: Some(iced::Background::Color(c.menu_hover)),
+                        text_color: c.menu_text,
+                        border: iced::Border::default(),
+                        ..Default::default()
+                    },
+                    _ => iced::widget::button::Style {
+                        background: Some(iced::Background::Color(c.menu_bg)),
+                        text_color: c.menu_text,
+                        border: iced::Border::default(),
+                        ..Default::default()
+                    },
+                },
+            );
 
             let menu_item = if let Some(command) = item.command {
                 menu_item.on_press(Message::MenuCommand(command))
@@ -980,4 +996,16 @@ mod tests {
         assert!(cut.enabled);
         assert_eq!(cut.command, Some(MenuCommand::Cut));
     }
+
+    /// Guards the compact menu geometry and Unicode submenu marker used by both popup types.
+    #[test]
+    fn shared_menu_metrics_keep_rows_compact_and_gutters_stable() {
+        assert!((24.0..=26.0).contains(&typography::MENU_ROW_HEIGHT));
+        assert!((10..=12).contains(&typography::MENU_ROW_HORIZONTAL_PADDING));
+        assert!((4..=5).contains(&typography::MENU_ROW_VERTICAL_PADDING));
+        assert!(typography::MENU_CHECK_GUTTER > 0.0);
+        assert!(typography::MENU_SHORTCUT_GUTTER > 0.0);
+        assert!(typography::MENU_ARROW_GUTTER > 0.0);
+        assert_eq!(typography::MENU_SUBMENU_ARROW, "›");
+    }
 }
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/panels/styles.rs b/hcie-iced-app/crates/hcie-iced-gui/src/panels/styles.rs
index 904bd21..9a1c83d 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/panels/styles.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/panels/styles.rs
@@ -11,6 +11,91 @@
 
 use crate::theme::ThemeColors;
 
+/// Distance between a hovered control and its balloon tooltip, in logical pixels.
+///
+/// **Purpose:** Keeps the balloon visually detached from narrow toolbox and
+/// toolbar controls instead of appearing attached to their outer edge.
+///
+/// **Logic & Workflow:** Iced applies this value along the tooltip placement
+/// axis after positioning the overlay beside the hovered control.
+///
+/// **Side Effects / Dependencies:** Consumed only by Iced tooltip layout.
+const TOOLTIP_CONTROL_GAP: u16 = 14;
+
+/// Builds the opaque elevated surface used by balloon-style tooltips.
+///
+/// **Purpose:** Keeps tooltip text readable over the canvas and every panel by
+/// drawing a fully opaque, theme-consistent surface with a rounded outline and
+/// subtle elevation shadow.
+///
+/// **Logic & Workflow:** Uses the active panel color as the tooltip fill,
+/// selects the high-contrast theme border, rounds the outline, and adds a small
+/// downward shadow to separate the balloon from the hovered control.
+///
+/// **Arguments:** `colors` contains the active application theme tokens.
+///
+/// **Returns:** An Iced 0.13 container style suitable for a tooltip overlay.
+///
+/// **Side Effects / Dependencies:** None. The returned style is deterministic
+/// and does not read or mutate application state.
+pub fn tooltip_balloon_background(colors: ThemeColors) -> iced::widget::container::Style {
+    let mut background = colors.bg_panel;
+    background.a = 1.0;
+
+    iced::widget::container::Style {
+        text_color: Some(colors.text_primary),
+        background: Some(iced::Background::Color(background)),
+        border: iced::Border::default()
+            .rounded(5)
+            .color(colors.border_high)
+            .width(1),
+        shadow: iced::Shadow {
+            color: iced::Color::from_rgba(0.0, 0.0, 0.0, 0.32),
+            offset: iced::Vector::new(0.0, 2.0),
+            blur_radius: 6.0,
+        },
+        ..Default::default()
+    }
+}
+
+/// Wraps an interactive control in a shared opaque balloon-style tooltip.
+///
+/// **Purpose:** Applies identical tooltip typography, spacing, viewport
+/// behavior, and visual treatment to toolbox and toolbar tool controls.
+///
+/// **Logic & Workflow:** Converts the supplied control and owned label into
+/// Iced elements, places the balloon at `position`, leaves a visible gap from
+/// the hovered control, applies compact internal padding, and delegates the
+/// overlay appearance to [`tooltip_balloon_background`].
+///
+/// **Arguments:** `content` is the hovered control; `label` is its tooltip
+/// text; `position` selects the overlay side; and `colors` supplies active
+/// theme tokens.
+///
+/// **Returns:** An Iced 0.13 element that preserves the wrapped control's
+/// messages and interaction behavior while displaying the styled tooltip.
+///
+/// **Side Effects / Dependencies:** Rendering depends on Iced's tooltip
+/// overlay system. Constructing the element performs no I/O or state mutation.
+pub fn balloon_tooltip<'a, Message: 'a>(
+    content: impl Into<iced::Element<'a, Message>>,
+    label: impl Into<String>,
+    position: iced::widget::tooltip::Position,
+    colors: ThemeColors,
+) -> iced::Element<'a, Message> {
+    iced::widget::tooltip(
+        content,
+        iced::widget::text(label.into())
+            .size(11)
+            .color(colors.text_primary),
+        position,
+    )
+    .gap(TOOLTIP_CONTROL_GAP)
+    .padding(7)
+    .style(move |_theme| tooltip_balloon_background(colors))
+    .into()
+}
+
 /// Panel background — #2a2a2a (Photopea panel color).
 pub fn panel_background(colors: ThemeColors) -> iced::widget::container::Style {
     iced::widget::container::Style {
@@ -175,3 +260,28 @@ pub fn modern_panel_header(colors: ThemeColors, focused: bool) -> iced::widget::
         ..Default::default()
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::tooltip_balloon_background;
+    use crate::theme::{ThemeColors, ThemePreset};
+
+    /// Verifies tooltip surfaces remain opaque and readable in dark and light themes.
+    #[test]
+    fn tooltip_balloon_is_opaque_and_uses_theme_contrast_tokens() {
+        for preset in [ThemePreset::Photopea, ThemePreset::ProLight] {
+            let colors = ThemeColors::get(preset);
+            let style = tooltip_balloon_background(colors);
+            let background = match style.background.unwrap() {
+                iced::Background::Color(background) => background,
+                iced::Background::Gradient(_) => panic!("tooltip background must be a solid color"),
+            };
+
+            assert_eq!(background.a, 1.0);
+            assert_eq!(style.text_color, Some(colors.text_primary));
+            assert_eq!(style.border.color, colors.border_high);
+            assert_eq!(style.border.width, 1.0);
+            assert!(style.shadow.blur_radius > 0.0);
+        }
+    }
+}
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/panels/title_bar.rs b/hcie-iced-app/crates/hcie-iced-gui/src/panels/title_bar.rs
index d890523..1cbcb0f 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/panels/title_bar.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/panels/title_bar.rs
@@ -9,6 +9,7 @@
 //! - Window controls: standard minimize/maximize/close
 
 use crate::app::Message;
+use crate::panels::typography;
 use crate::theme::ThemeColors;
 use iced::widget::{button, container, mouse_area, row, text};
 use iced::{Element, Length};
@@ -21,11 +22,11 @@ pub(crate) const MENU_LABELS: &[&str] = &[
 /// Horizontal title-menu metrics shared by button layout and dropdown placement.
 ///
 /// **Purpose:** Keeps menu buttons and dropdown anchors in one deterministic layout model.
-/// **Logic & Workflow:** Widths include the measured 13px semibold label advance plus the
-/// title button's 16px horizontal padding. [`menu_anchor_x`] sums these exact rendered widths.
+/// **Logic & Workflow:** Widths include the measured 12px medium label advance plus the
+/// title button's 20px horizontal padding. [`menu_anchor_x`] sums these exact rendered widths.
 /// **Side Effects / Dependencies:** Values depend on the title bar font and padding below.
 pub(crate) const MENU_BUTTON_WIDTHS: &[f32] =
-    &[42.0, 42.0, 52.0, 56.0, 60.0, 51.0, 47.0, 67.0, 50.0];
+    &[46.0, 46.0, 56.0, 60.0, 64.0, 55.0, 51.0, 71.0, 54.0];
 pub(crate) const MENU_LEFT_INSET: f32 = 4.0;
 /// Unified menu/title bar height shared with dropdown placement.
 pub(crate) const MENU_BAR_HEIGHT: f32 = 28.0;
@@ -58,17 +59,21 @@ pub fn view<'a>(
     colors: ThemeColors,
     active_menu: Option<usize>,
 ) -> Element<'a, Message> {
-    // ── Menu items — Photopea style: 12px, tight padding ──
+    // ── Menu items — readable 12px medium labels with balanced padding ──
     let mut menu_items = row![].spacing(0);
     for (idx, &label) in MENU_LABELS.iter().enumerate() {
         let is_open = active_menu == Some(idx);
         let c = colors;
-        let btn = button(text(label).size(13).font(iced::Font {
-            weight: iced::font::Weight::Semibold,
-            ..iced::Font::default()
-        }))
+        let btn = button(
+            text(label)
+                .size(typography::MENU_BAR_LABEL)
+                .font(iced::Font {
+                    weight: iced::font::Weight::Medium,
+                    ..iced::Font::default()
+                }),
+        )
         .on_press(Message::MenuOpen(idx))
-        .padding([3, 8])
+        .padding([3, 10])
         .width(MENU_BUTTON_WIDTHS[idx])
         .style(
             move |_theme: &iced::Theme, status: iced::widget::button::Status| {
@@ -232,8 +237,8 @@ mod tests {
     #[test]
     fn menu_anchors_are_deterministic_across_viewport_widths() {
         assert_eq!(menu_anchor_x(0, 1280.0, 260.0), 4.0);
-        assert_eq!(menu_anchor_x(3, 1280.0, 260.0), 140.0);
-        assert_eq!(menu_anchor_x(8, 1280.0, 260.0), 421.0);
+        assert_eq!(menu_anchor_x(3, 1280.0, 260.0), 152.0);
+        assert_eq!(menu_anchor_x(8, 1280.0, 260.0), 453.0);
         assert_eq!(menu_anchor_x(8, 500.0, 260.0), 240.0);
         assert_eq!(menu_anchor_x(8, 180.0, 260.0), 0.0);
     }
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/panels/toolbar.rs b/hcie-iced-app/crates/hcie-iced-gui/src/panels/toolbar.rs
index 1d20fec..a8704c6 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/panels/toolbar.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/panels/toolbar.rs
@@ -208,7 +208,7 @@ fn svg_btn(
         text("?").size(12).color(c.text_primary).into()
     };
 
-    iced::widget::tooltip(
+    styles::balloon_tooltip(
         button(icon).on_press(msg).padding([2, 4]).style(
             move |_theme: &iced::Theme, status: iced::widget::button::Status| match status {
                 iced::widget::button::Status::Hovered => iced::widget::button::Style {
@@ -225,10 +225,10 @@ fn svg_btn(
                 },
             },
         ),
-        text(tip_owned).size(11),
+        tip_owned,
         iced::widget::tooltip::Position::Bottom,
+        colors,
     )
-    .into()
 }
 
 fn small_btn(label: &str, colors: ThemeColors) -> Element<'static, Message> {
@@ -268,10 +268,10 @@ fn sep(colors: ThemeColors) -> Element<'static, Message> {
 
 /// Displays a compact toolbar value while moving its full meaning into a tooltip.
 fn compact_value(value: String, tip: &str, colors: ThemeColors) -> Element<'static, Message> {
-    iced::widget::tooltip(
+    styles::balloon_tooltip(
         container(text(value).size(10).color(colors.text_primary)).padding([1, 3]),
-        text(tip.to_string()).size(11),
+        tip,
         iced::widget::tooltip::Position::Bottom,
+        colors,
     )
-    .into()
 }
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/panels/typography.rs b/hcie-iced-app/crates/hcie-iced-gui/src/panels/typography.rs
index a83d4c6..9278730 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/panels/typography.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/panels/typography.rs
@@ -1,8 +1,9 @@
-//! Shared typography metrics for docked panels.
+//! Shared typography and compact menu metrics for the Iced interface.
 //!
-//! Purpose: Keep panel body, section, and dock-title text readable and consistent.
-//! Logic & Workflow: Panel views use these constants instead of local pixel sizes so narrow
-//! layouts can increase readability without diverging. Side Effects / Dependencies: None.
+//! Purpose: Keep panel text and menu rows readable, aligned, and consistent.
+//! Logic & Workflow: Panel and menu views use these constants instead of local pixel sizes;
+//! fixed menu gutters keep labels stable when checkmarks, shortcuts, or submenus are absent.
+//! Side Effects / Dependencies: None.
 
 /// Standard readable body text size used by panel labels and values.
 pub const BODY: u16 = 12;
@@ -10,3 +11,24 @@ pub const BODY: u16 = 12;
 pub const SECTION: u16 = 13;
 /// Dock title size used by pane title bars.
 pub const TITLE: u16 = 13;
+
+/// Normal-sized text used by labels in the top application menu bar.
+pub const MENU_BAR_LABEL: u16 = 12;
+/// Normal-sized text used by dropdown and context-menu labels.
+pub const MENU_LABEL: u16 = 13;
+/// Slightly smaller normal text used by menu keyboard shortcuts.
+pub const MENU_SHORTCUT: u16 = 12;
+/// Compact row height that vertically centers menu text in a 24-26px target.
+pub const MENU_ROW_HEIGHT: f32 = 26.0;
+/// Horizontal inset applied to both sides of every menu row.
+pub const MENU_ROW_HORIZONTAL_PADDING: u16 = 11;
+/// Vertical inset applied above and below the contents of every menu row.
+pub const MENU_ROW_VERTICAL_PADDING: u16 = 4;
+/// Reserved leading column width for checked and unchecked menu entries.
+pub const MENU_CHECK_GUTTER: f32 = 18.0;
+/// Reserved trailing column width for present and absent keyboard shortcuts.
+pub const MENU_SHORTCUT_GUTTER: f32 = 82.0;
+/// Reserved trailing column width for present and absent submenu arrows.
+pub const MENU_ARROW_GUTTER: f32 = 14.0;
+/// Readable single-character marker used for submenu navigation.
+pub const MENU_SUBMENU_ARROW: &str = "›";
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/selection/transform.rs b/hcie-iced-app/crates/hcie-iced-gui/src/selection/transform.rs
index 876ca56..838bf3d 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/selection/transform.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/selection/transform.rs
@@ -37,10 +37,11 @@ impl SelectionTransform {
         let mut max_x = 0u32;
         let mut max_y = 0u32;
 
-        // Find bounding box of non-zero mask pixels
+        // Find bounding box of non-zero mask pixels.
+        // The mask is one byte per pixel (w*h bytes), NOT RGBA (w*h*4 bytes).
         for y in 0..canvas_h {
             for x in 0..canvas_w {
-                let idx = ((y * canvas_w + x) * 4 + 3) as usize;
+                let idx = (y * canvas_w + x) as usize;
                 if idx < mask.len() && mask[idx] > 0 {
                     min_x = min_x.min(x);
                     min_y = min_y.min(y);
@@ -57,9 +58,9 @@ impl SelectionTransform {
         let width = max_x - min_x + 1;
         let height = max_y - min_y + 1;
 
-        // Extract RGBA pixels within the bounding box
+        // Extract RGBA pixels within the bounding box from the active layer.
         let mut pixels = vec![0u8; (width * height * 4) as usize];
-        let comp = engine.get_composite_pixels();
+        let layer_pixels = engine.get_active_layer_pixels().unwrap_or_default();
 
         for y in 0..height {
             for x in 0..width {
@@ -68,18 +69,20 @@ impl SelectionTransform {
                 let src_idx = ((src_y * canvas_w + src_x) * 4) as usize;
                 let dst_idx = ((y * width + x) * 4) as usize;
 
-                if src_idx + 3 < comp.len() && dst_idx + 3 < pixels.len() {
-                    let mask_idx = ((src_y * canvas_w + src_x) * 4 + 3) as usize;
+                if src_idx + 3 < layer_pixels.len() && dst_idx + 3 < pixels.len() {
+                    // Mask is one byte per pixel
+                    let mask_idx = (src_y * canvas_w + src_x) as usize;
                     let alpha = if mask_idx < mask.len() {
                         mask[mask_idx]
                     } else {
                         0
                     };
 
-                    pixels[dst_idx] = comp[src_idx];
-                    pixels[dst_idx + 1] = comp[src_idx + 1];
-                    pixels[dst_idx + 2] = comp[src_idx + 2];
-                    pixels[dst_idx + 3] = alpha;
+                    pixels[dst_idx] = layer_pixels[src_idx];
+                    pixels[dst_idx + 1] = layer_pixels[src_idx + 1];
+                    pixels[dst_idx + 2] = layer_pixels[src_idx + 2];
+                    pixels[dst_idx + 3] =
+                        ((layer_pixels[src_idx + 3] as u16 * alpha as u16) / 255) as u8;
                 }
             }
         }
@@ -117,46 +120,11 @@ impl SelectionTransform {
     /// **Returns:** The nearest resize/rotate/move handle or `None`. **Side Effects:** None.
     pub fn hit_test(&self, x: f32, y: f32, zoom: f32) -> TransformHandle {
         let half = TransformHandle::HANDLE_SIZE / zoom.max(0.01) * 0.5;
-        let points = [
-            (TransformHandle::TopLeft, self.pos.x, self.pos.y),
-            (
-                TransformHandle::TopRight,
-                self.pos.x + self.size.x,
-                self.pos.y,
-            ),
-            (
-                TransformHandle::BottomLeft,
-                self.pos.x,
-                self.pos.y + self.size.y,
-            ),
-            (
-                TransformHandle::BottomRight,
-                self.pos.x + self.size.x,
-                self.pos.y + self.size.y,
-            ),
-            (
-                TransformHandle::Top,
-                self.pos.x + self.size.x * 0.5,
-                self.pos.y,
-            ),
-            (
-                TransformHandle::Bottom,
-                self.pos.x + self.size.x * 0.5,
-                self.pos.y + self.size.y,
-            ),
-            (
-                TransformHandle::Left,
-                self.pos.x,
-                self.pos.y + self.size.y * 0.5,
-            ),
-            (
-                TransformHandle::Right,
-                self.pos.x + self.size.x,
-                self.pos.y + self.size.y * 0.5,
-            ),
-        ];
-        let rotate_x = self.pos.x + self.size.x * 0.5;
-        let rotate_y = self.pos.y - TransformHandle::ROTATE_OFFSET / zoom.max(0.01);
+        let points = TransformHandle::RESIZE_HANDLES.map(|handle| {
+            let (hx, hy) = self.handle_position(handle, zoom);
+            (handle, hx, hy)
+        });
+        let (rotate_x, rotate_y) = self.handle_position(TransformHandle::Rotate, zoom);
         if (x - rotate_x).hypot(y - rotate_y) <= half {
             return TransformHandle::Rotate;
         }
@@ -165,10 +133,11 @@ impl SelectionTransform {
                 return handle;
             }
         }
-        if x >= self.pos.x
-            && x <= self.pos.x + self.size.x
-            && y >= self.pos.y
-            && y <= self.pos.y + self.size.y
+        let (local_x, local_y) = self.inverse_rotate_point(x, y);
+        if local_x >= self.pos.x
+            && local_x <= self.pos.x + self.size.x
+            && local_y >= self.pos.y
+            && local_y <= self.pos.y + self.size.y
         {
             TransformHandle::Move
         } else {
@@ -176,6 +145,131 @@ impl SelectionTransform {
         }
     }
 
+    /// Returns a transform handle's position after rotating it around the selection center.
+    ///
+    /// **Purpose:** Keeps painted handles, pointer hit-testing, and cursor routing on the same
+    /// geometry for translated, scaled, and rotated selections.
+    ///
+    /// **Logic & Workflow:** Resolves the handle in the unrotated box, applies the transform's
+    /// forward rotation around its center, and places the rotate handle at a screen-constant
+    /// offset above the top edge before rotation.
+    ///
+    /// **Arguments:** `handle` identifies the requested control and `zoom` converts the rotate
+    /// offset from screen pixels to canvas units. **Returns:** The canvas-space `(x, y)` point.
+    ///
+    /// **Side Effects / Dependencies:** None; the calculation uses only transform geometry.
+    pub fn handle_position(&self, handle: TransformHandle, zoom: f32) -> (f32, f32) {
+        let x = self.pos.x;
+        let y = self.pos.y;
+        let w = self.size.x;
+        let h = self.size.y;
+        let point = match handle {
+            TransformHandle::TopLeft => (x, y),
+            TransformHandle::TopRight => (x + w, y),
+            TransformHandle::BottomLeft => (x, y + h),
+            TransformHandle::BottomRight => (x + w, y + h),
+            TransformHandle::Top => (x + w * 0.5, y),
+            TransformHandle::Bottom => (x + w * 0.5, y + h),
+            TransformHandle::Left => (x, y + h * 0.5),
+            TransformHandle::Right => (x + w, y + h * 0.5),
+            TransformHandle::Rotate => (
+                x + w * 0.5,
+                y - TransformHandle::ROTATE_OFFSET / zoom.max(0.01),
+            ),
+            TransformHandle::Move | TransformHandle::None => (x + w * 0.5, y + h * 0.5),
+        };
+        self.rotate_point(point.0, point.1)
+    }
+
+    /// Rotates a canvas point forward around this transform's center.
+    ///
+    /// **Purpose:** Supplies one forward-affine definition for handles and bounds.
+    /// **Logic & Workflow:** Translates to the center, applies the standard 2D rotation matrix,
+    /// then translates back. **Arguments:** `x` and `y` are canvas coordinates. **Returns:** The
+    /// rotated point. **Side Effects / Dependencies:** None.
+    pub fn rotate_point(&self, x: f32, y: f32) -> (f32, f32) {
+        let cx = self.pos.x + self.size.x * 0.5;
+        let cy = self.pos.y + self.size.y * 0.5;
+        let dx = x - cx;
+        let dy = y - cy;
+        let cos = self.rotation.cos();
+        let sin = self.rotation.sin();
+        (cx + dx * cos - dy * sin, cy + dx * sin + dy * cos)
+    }
+
+    /// Inverse-rotates a canvas point into the transform's unrotated box space.
+    ///
+    /// **Purpose:** Allows move hit-testing and inverse-affine pixel sampling to agree.
+    /// **Logic & Workflow:** Applies the transpose of the forward rotation matrix around the
+    /// transform center. **Arguments:** `x` and `y` are canvas coordinates. **Returns:** The
+    /// corresponding unrotated point. **Side Effects / Dependencies:** None.
+    pub fn inverse_rotate_point(&self, x: f32, y: f32) -> (f32, f32) {
+        let cx = self.pos.x + self.size.x * 0.5;
+        let cy = self.pos.y + self.size.y * 0.5;
+        let dx = x - cx;
+        let dy = y - cy;
+        let cos = self.rotation.cos();
+        let sin = self.rotation.sin();
+        (cx + dx * cos + dy * sin, cy - dx * sin + dy * cos)
+    }
+
+    /// Resizes a potentially rotated transform while anchoring the opposite edge or corner.
+    ///
+    /// **Purpose:** Makes drag deltas follow the visual handle axes after rotation instead of the
+    /// canvas axes. **Logic & Workflow:** Projects the canvas delta into local box space, moves the
+    /// selected local edges, clamps them to a one-pixel minimum, then rotates the local center shift
+    /// back into canvas space and rebuilds `pos`/`size` around the shifted center.
+    ///
+    /// **Arguments:** `handle` is a resize handle and `canvas_dx`/`canvas_dy` are incremental pointer
+    /// deltas. **Returns:** Nothing. **Side Effects / Dependencies:** Mutates geometry only; move,
+    /// rotate, and none handles are ignored.
+    pub fn resize_from_delta(&mut self, handle: TransformHandle, canvas_dx: f32, canvas_dy: f32) {
+        let cos = self.rotation.cos();
+        let sin = self.rotation.sin();
+        let local_dx = canvas_dx * cos + canvas_dy * sin;
+        let local_dy = -canvas_dx * sin + canvas_dy * cos;
+        let mut left = -self.size.x * 0.5;
+        let mut right = self.size.x * 0.5;
+        let mut top = -self.size.y * 0.5;
+        let mut bottom = self.size.y * 0.5;
+        if matches!(
+            handle,
+            TransformHandle::TopLeft | TransformHandle::BottomLeft | TransformHandle::Left
+        ) {
+            left = (left + local_dx).min(right - 1.0);
+        }
+        if matches!(
+            handle,
+            TransformHandle::TopRight | TransformHandle::BottomRight | TransformHandle::Right
+        ) {
+            right = (right + local_dx).max(left + 1.0);
+        }
+        if matches!(
+            handle,
+            TransformHandle::TopLeft | TransformHandle::TopRight | TransformHandle::Top
+        ) {
+            top = (top + local_dy).min(bottom - 1.0);
+        }
+        if matches!(
+            handle,
+            TransformHandle::BottomLeft | TransformHandle::BottomRight | TransformHandle::Bottom
+        ) {
+            bottom = (bottom + local_dy).max(top + 1.0);
+        }
+        if matches!(
+            handle,
+            TransformHandle::Move | TransformHandle::Rotate | TransformHandle::None
+        ) {
+            return;
+        }
+        let local_center_x = (left + right) * 0.5;
+        let local_center_y = (top + bottom) * 0.5;
+        let center_x = self.pos.x + self.size.x * 0.5 + local_center_x * cos - local_center_y * sin;
+        let center_y = self.pos.y + self.size.y * 0.5 + local_center_x * sin + local_center_y * cos;
+        self.size = Vector::new(right - left, bottom - top);
+        self.pos = Vector::new(center_x - self.size.x * 0.5, center_y - self.size.y * 0.5);
+    }
+
     /// Enforces positive finite geometry and optionally preserves source aspect ratio.
     ///
     /// **Arguments:** `lock_aspect` applies the source pixel ratio when true. **Returns:** Nothing.
@@ -232,6 +326,18 @@ impl TransformHandle {
     /// Size of rotation handle offset from top center.
     pub const ROTATE_OFFSET: f32 = 20.0;
 
+    /// Resize handles in hit-test priority order, with corners preceding edge handles.
+    pub const RESIZE_HANDLES: [Self; 8] = [
+        Self::TopLeft,
+        Self::TopRight,
+        Self::BottomLeft,
+        Self::BottomRight,
+        Self::Top,
+        Self::Bottom,
+        Self::Left,
+        Self::Right,
+    ];
+
     /// Get cursor icon hint for this handle.
     pub fn cursor_hint(&self) -> &'static str {
         match self {
@@ -245,3 +351,137 @@ impl TransformHandle {
         }
     }
 }
+
+/// Computes the canvas-clipped axis-aligned pixel footprint of a transformed selection.
+///
+/// **Purpose:** Prevents rotated corners from being clipped and gives preview restoration and
+/// partial GPU upload code the exact same destination extent as the rasterizer.
+///
+/// **Logic & Workflow:** Rotates all four box corners, floors the minimum coordinates, ceils the
+/// maximum coordinates, then clips the exclusive rectangle to the canvas.
+///
+/// **Arguments:** `transform` supplies affine geometry; `canvas_width` and `canvas_height` define
+/// clipping limits. **Returns:** `Some([x0, y0, x1, y1])` or `None` for an empty/off-canvas result.
+///
+/// **Side Effects / Dependencies:** None and performs no allocation.
+pub fn transformed_bounds(
+    transform: &SelectionTransform,
+    canvas_width: u32,
+    canvas_height: u32,
+) -> Option<[u32; 4]> {
+    if transform.is_empty() || canvas_width == 0 || canvas_height == 0 {
+        return None;
+    }
+    let corners = [
+        transform.rotate_point(transform.pos.x, transform.pos.y),
+        transform.rotate_point(transform.pos.x + transform.size.x, transform.pos.y),
+        transform.rotate_point(transform.pos.x, transform.pos.y + transform.size.y),
+        transform.rotate_point(
+            transform.pos.x + transform.size.x,
+            transform.pos.y + transform.size.y,
+        ),
+    ];
+    let min_x = corners.iter().map(|p| p.0).fold(f32::INFINITY, f32::min);
+    let min_y = corners.iter().map(|p| p.1).fold(f32::INFINITY, f32::min);
+    let max_x = corners
+        .iter()
+        .map(|p| p.0)
+        .fold(f32::NEG_INFINITY, f32::max);
+    let max_y = corners
+        .iter()
+        .map(|p| p.1)
+        .fold(f32::NEG_INFINITY, f32::max);
+    let x0 = min_x.floor().max(0.0).min(canvas_width as f32) as u32;
+    let y0 = min_y.floor().max(0.0).min(canvas_height as f32) as u32;
+    let x1 = max_x.ceil().max(0.0).min(canvas_width as f32) as u32;
+    let y1 = max_y.ceil().max(0.0).min(canvas_height as f32) as u32;
+    (x0 < x1 && y0 < y1).then_some([x0, y0, x1, y1])
+}
+
+/// Calculates rotation from the pointer's angular delta relative to drag start.
+///
+/// **Purpose:** Prevents the rotate handle from jumping to an absolute pointer angle on press.
+/// **Logic & Workflow:** Measures start and current angles around the original transform center and
+/// adds their difference to the original rotation. **Arguments:** `original` is drag-start geometry;
+/// `start` and `current` are canvas pointer coordinates. **Returns:** The updated angle in radians.
+/// **Side Effects / Dependencies:** None.
+pub fn rotation_from_drag(
+    original: &SelectionTransform,
+    start: (f32, f32),
+    current: (f32, f32),
+) -> f32 {
+    let center_x = original.pos.x + original.size.x * 0.5;
+    let center_y = original.pos.y + original.size.y * 0.5;
+    let start_angle = (start.1 - center_y).atan2(start.0 - center_x);
+    let current_angle = (current.1 - center_y).atan2(current.0 - center_x);
+    original.rotation + current_angle - start_angle
+}
+
+/// Source-over composites a transformed selection into an existing canvas buffer.
+///
+/// **Purpose:** Provides one inverse-affine nearest-neighbor sampler for both interactive preview
+/// and final apply, including scaling, rotation, negative placement, and rotated AABB coverage.
+///
+/// **Logic & Workflow:** Iterates only the clipped transformed AABB, maps each destination pixel
+/// center through inverse rotation and scale into source pixel-center space, and alpha-composites
+/// valid source samples onto `destination` without allocating another image.
+///
+/// **Arguments:** `destination` is canvas RGBA data, `canvas_width`/`canvas_height` describe its
+/// stride and clipping area, and `transform` supplies source pixels and affine geometry.
+/// **Returns:** The affected clipped AABB, or `None` if no rasterization is possible.
+///
+/// **Side Effects / Dependencies:** Mutates only pixels inside the returned bounds; no I/O or
+/// allocation is performed.
+pub fn composite_transform(
+    destination: &mut [u8],
+    canvas_width: u32,
+    canvas_height: u32,
+    transform: &SelectionTransform,
+) -> Option<[u32; 4]> {
+    let bounds = transformed_bounds(transform, canvas_width, canvas_height)?;
+    if destination.len() < canvas_width as usize * canvas_height as usize * 4 {
+        return None;
+    }
+    let source_width = transform.width as f32;
+    let source_height = transform.height as f32;
+    let center_x = transform.pos.x + transform.size.x * 0.5;
+    let center_y = transform.pos.y + transform.size.y * 0.5;
+    let cos = transform.rotation.cos();
+    let sin = transform.rotation.sin();
+    for y in bounds[1]..bounds[3] {
+        for x in bounds[0]..bounds[2] {
+            let dx = x as f32 + 0.5 - center_x;
+            let dy = y as f32 + 0.5 - center_y;
+            let local_x = dx * cos + dy * sin + transform.size.x * 0.5;
+            let local_y = -dx * sin + dy * cos + transform.size.y * 0.5;
+            let source_x = local_x / transform.size.x.max(1.0e-6) * source_width - 0.5;
+            let source_y = local_y / transform.size.y.max(1.0e-6) * source_height - 0.5;
+            let sx = source_x.round() as i32;
+            let sy = source_y.round() as i32;
+            if sx < 0 || sy < 0 || sx >= transform.width as i32 || sy >= transform.height as i32 {
+                continue;
+            }
+            let source_index = (sy as usize * transform.width as usize + sx as usize) * 4;
+            let destination_index = (y as usize * canvas_width as usize + x as usize) * 4;
+            if source_index + 3 >= transform.pixels.len() {
+                continue;
+            }
+            let source_alpha = transform.pixels[source_index + 3] as f32 / 255.0;
+            if source_alpha <= 0.0 {
+                continue;
+            }
+            let destination_alpha = destination[destination_index + 3] as f32 / 255.0;
+            let output_alpha = source_alpha + destination_alpha * (1.0 - source_alpha);
+            for channel in 0..3 {
+                let source = transform.pixels[source_index + channel] as f32;
+                let destination_channel = destination[destination_index + channel] as f32;
+                destination[destination_index + channel] = ((source * source_alpha
+                    + destination_channel * destination_alpha * (1.0 - source_alpha))
+                    / output_alpha)
+                    .round() as u8;
+            }
+            destination[destination_index + 3] = (output_alpha * 255.0).round() as u8;
+        }
+    }
+    Some(bounds)
+}
diff --git a/hcie-iced-app/crates/hcie-iced-gui/src/sidebar/mod.rs b/hcie-iced-app/crates/hcie-iced-gui/src/sidebar/mod.rs
index 59721c6..60560f6 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/src/sidebar/mod.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/src/sidebar/mod.rs
@@ -163,6 +163,7 @@ pub fn view<'a>(
     expanded: bool,
 ) -> Element<'a, Message> {
     let sidebar_width = if expanded { 72 } else { 36 };
+    log::info!("[sidebar] expanded={} active_slot={} sub_tools_open={}", expanded, active_slot, sub_tools_open);
 
     // Tool buttons — single column or 2-column grid depending on expanded state
     let mut tool_list = column![].spacing(1);
@@ -536,7 +537,7 @@ fn tool_button<'a>(
     );
 
     let popup_affordance: Element<'a, Message> = if has_sub_tools {
-        iced::widget::tooltip(
+        styles::balloon_tooltip(
             button(text("▸").size(12).color(colors.text_primary))
                 .on_press(Message::SubtoolsToggle(slot_idx))
                 .padding(0)
@@ -553,10 +554,10 @@ fn tool_button<'a>(
                     border: iced::Border::default(),
                     ..Default::default()
                 }),
-            text(format!("Open {} sub-tools", slot.label)).size(11),
+            format!("Open {} sub-tools", slot.label),
             iced::widget::tooltip::Position::Right,
+            colors,
         )
-        .into()
     } else {
         iced::widget::Space::with_width(0).into()
     };
@@ -611,47 +612,57 @@ fn tool_button<'a>(
                         .into()
                 };
 
-            let item = button(container(popup_icon).width(32).height(28).center(18))
-                .on_press(Message::ToolSelected(tool))
-                .padding(0)
+            // Wrap the icon in a fixed-size, centered container so the popup
+            // button always occupies 32×28 pixels even when the SVG is still
+            // loading or the text fallback is used.
+            let icon_container = container(popup_icon)
+                .width(20)
+                .height(20)
+                .center_x(Length::Fill)
+                .center_y(Length::Fill);
+            let item_content = container(icon_container)
                 .width(32)
-                .height(28)
-                .style(
-                    move |_theme: &iced::Theme, status: iced::widget::button::Status| match status {
-                        iced::widget::button::Status::Hovered => iced::widget::button::Style {
-                            background: Some(iced::Background::Color(if is_tool_active {
-                                c.accent_green
-                            } else {
-                                c.bg_hover
-                            })),
-                            text_color: c.text_primary,
-                            border: iced::Border::default()
-                                .color(if is_tool_active {
-                                    c.accent
-                                } else {
-                                    c.border_high
-                                })
-                                .width(if is_tool_active { 1 } else { 0 }),
-                            ..Default::default()
-                        },
-                        _ => iced::widget::button::Style {
-                            background: Some(iced::Background::Color(if is_tool_active {
-                                c.accent_green
-                            } else {
-                                c.bg_active
-                            })),
-                            text_color: c.text_primary,
-                            border: iced::Border::default()
-                                .color(if is_tool_active {
-                                    c.accent
-                                } else {
-                                    c.border_high
-                                })
-                                .width(if is_tool_active { 1 } else { 0 }),
-                            ..Default::default()
-                        },
+                .height(28);
+
+            let item = button(
+                container(item_content)
+                    .width(32)
+                    .height(28)
+                    .center_x(Length::Fill)
+                    .center_y(Length::Fill),
+            )
+            .on_press(Message::ToolSelected(tool))
+            .padding(0)
+            .width(32)
+            .height(28)
+            .style(
+                move |_theme: &iced::Theme, status: iced::widget::button::Status| match status {
+                    iced::widget::button::Status::Hovered => iced::widget::button::Style {
+                        background: Some(iced::Background::Color(if is_tool_active {
+                            c.accent_green
+                        } else {
+                            c.bg_hover
+                        })),
+                        text_color: c.text_primary,
+                        border: iced::Border::default()
+                            .color(if is_tool_active { c.accent } else { c.border_high })
+                            .width(if is_tool_active { 1 } else { 0 }),
+                        ..Default::default()
                     },
-                );
+                    _ => iced::widget::button::Style {
+                        background: Some(iced::Background::Color(if is_tool_active {
+                            c.accent_green
+                        } else {
+                            c.bg_active
+                        })),
+                        text_color: c.text_primary,
+                        border: iced::Border::default()
+                            .color(if is_tool_active { c.accent } else { c.border_high })
+                            .width(if is_tool_active { 1 } else { 0 }),
+                        ..Default::default()
+                    },
+                },
+            );
 
             let shortcut = tool_shortcut(tool);
             let tooltip_text = if shortcut.is_empty() {
@@ -659,10 +670,11 @@ fn tool_button<'a>(
             } else {
                 format!("{tool_name} ({shortcut})")
             };
-            popup_row = popup_row.push(iced::widget::tooltip(
+            popup_row = popup_row.push(styles::balloon_tooltip(
                 item,
-                text(tooltip_text).size(11),
+                tooltip_text,
                 iced::widget::tooltip::Position::Right,
+                colors,
             ));
             if (tool_index + 1) % 2 == 0 || tool_index + 1 == slot.tools.len() {
                 popup_grid = popup_grid.push(popup_row);
@@ -684,10 +696,11 @@ fn tool_button<'a>(
                 ..Default::default()
             });
 
-        let parent = container(iced::widget::tooltip(
+        let parent = container(styles::balloon_tooltip(
             btn_element,
-            iced::widget::text(format!("{} (sub-tools open)", slot.label)).size(11),
+            format!("{} (sub-tools open)", slot.label),
             iced::widget::tooltip::Position::Right,
+            colors,
         ))
         .width(68);
         container(column![parent, popup].spacing(1))
@@ -696,12 +709,12 @@ fn tool_button<'a>(
     } else {
         // Tooltip on hover
         let tooltip_text = slot.label.to_string();
-        iced::widget::tooltip(
+        styles::balloon_tooltip(
             btn_element,
-            iced::widget::text(tooltip_text).size(11),
+            tooltip_text,
             iced::widget::tooltip::Position::Right,
+            colors,
         )
-        .into()
     }
 }
 
diff --git a/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs b/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs
index 071190e..096453b 100644
--- a/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs
+++ b/hcie-iced-app/crates/hcie-iced-gui/tests/selection_test.rs
@@ -2,6 +2,9 @@
 
 use hcie_iced_gui::selection::clipboard::centered_transform;
 use hcie_iced_gui::selection::state::{combine_masks, mask_bounds, selected_spans};
+use hcie_iced_gui::selection::transform::{
+    composite_transform, rotation_from_drag, transformed_bounds,
+};
 use hcie_iced_gui::selection::{CropState, SelectionMode, SelectionTransform, TransformHandle};
 
 #[test]
@@ -122,3 +125,91 @@ fn clipboard_transform_is_centered_and_transform_geometry_is_safe() {
     assert!(transform.size.x > 0.0 && transform.size.y > 0.0);
     assert!((transform.size.x / transform.size.y - 2.0).abs() < 0.001);
 }
+
+/// Verifies that the shared inverse-affine rasterizer preserves identity placement exactly.
+///
+/// **Purpose:** Guards preview/apply parity for the common unscaled move path.
+/// **Logic & Workflow:** Composites a two-pixel opaque source into an empty canvas and compares the
+/// exact affected pixels and returned bounds. **Arguments & Returns:** No arguments or return value;
+/// failed assertions identify sampling drift. **Side Effects / Dependencies:** None.
+#[test]
+fn inverse_affine_identity_sampling_is_exact() {
+    let transform = SelectionTransform {
+        pixels: vec![255, 0, 0, 255, 0, 255, 0, 255],
+        width: 2,
+        height: 1,
+        pos: iced::Vector::new(1.0, 2.0),
+        size: iced::Vector::new(2.0, 1.0),
+        rotation: 0.0,
+    };
+    let mut canvas = vec![0; 4 * 4 * 4];
+    assert_eq!(
+        composite_transform(&mut canvas, 4, 4, &transform),
+        Some([1, 2, 3, 3])
+    );
+    assert_eq!(&canvas[(2 * 4 + 1) * 4..(2 * 4 + 3) * 4], transform.pixels);
+}
+
+/// Verifies that rotated bounds include every corner rather than clipping to the unrotated box.
+///
+/// **Purpose:** Protects dirty restoration, partial upload, and final apply from rotated-corner
+/// clipping. **Logic & Workflow:** Rotates a square by 45 degrees and checks its expanded integer
+/// AABB. **Arguments & Returns:** No arguments or return value. **Side Effects / Dependencies:** None.
+#[test]
+fn rotated_bounds_expand_to_cover_corners() {
+    let transform = SelectionTransform {
+        pixels: vec![255; 2 * 2 * 4],
+        width: 2,
+        height: 2,
+        pos: iced::Vector::new(4.0, 4.0),
+        size: iced::Vector::new(2.0, 2.0),
+        rotation: std::f32::consts::FRAC_PI_4,
+    };
+    assert_eq!(transformed_bounds(&transform, 10, 10), Some([3, 3, 7, 7]));
+}
+
+/// Verifies rotated handle hit-testing and opposite-corner anchoring during resize.
+///
+/// **Purpose:** Guards cursor routing and rotated scaling geometry together.
+/// **Logic & Workflow:** Hit-tests the transformed top-left point, resizes from that handle, and
+/// confirms the opposite corner remains fixed. **Arguments & Returns:** None. **Side Effects:** None.
+#[test]
+fn rotated_handle_hit_test_and_resize_share_geometry() {
+    let mut transform = SelectionTransform {
+        pixels: vec![255; 4 * 2 * 4],
+        width: 4,
+        height: 2,
+        pos: iced::Vector::new(4.0, 4.0),
+        size: iced::Vector::new(4.0, 2.0),
+        rotation: std::f32::consts::FRAC_PI_2,
+    };
+    let top_left = transform.handle_position(TransformHandle::TopLeft, 1.0);
+    assert_eq!(
+        transform.hit_test(top_left.0, top_left.1, 1.0),
+        TransformHandle::TopLeft
+    );
+    let anchored = transform.handle_position(TransformHandle::BottomRight, 1.0);
+    transform.resize_from_delta(TransformHandle::TopLeft, 0.0, 1.0);
+    let after = transform.handle_position(TransformHandle::BottomRight, 1.0);
+    assert!((anchored.0 - after.0).abs() < 0.001);
+    assert!((anchored.1 - after.1).abs() < 0.001);
+}
+
+/// Verifies rotation uses drag-start delta and retains pre-existing rotation.
+///
+/// **Purpose:** Prevents the first rotate move from jumping to an absolute angle.
+/// **Logic & Workflow:** Starts from a non-zero rotation and applies a quarter-turn pointer delta.
+/// **Arguments & Returns:** None. **Side Effects / Dependencies:** None.
+#[test]
+fn rotation_drag_adds_delta_to_original_angle() {
+    let transform = SelectionTransform {
+        pixels: vec![255; 4],
+        width: 1,
+        height: 1,
+        pos: iced::Vector::new(4.5, 4.5),
+        size: iced::Vector::new(1.0, 1.0),
+        rotation: 0.25,
+    };
+    let angle = rotation_from_drag(&transform, (6.0, 5.0), (5.0, 6.0));
+    assert!((angle - (0.25 + std::f32::consts::FRAC_PI_2)).abs() < 0.001);
+}