feat: Add theme and font management for egui GUI

- Introduced `theme.rs` to handle visual themes, font discovery, and application of theme colors.
- Implemented system font registration for Linux, macOS, and Windows.
- Added `apply_theme` function to configure egui visuals based on selected theme presets.

feat: Implement interactive tool state management

- Created `tool_state.rs` to manage runtime tool, selection, and transform states.
- Defined `ToolState` struct to encapsulate active tool, color settings, drawing states, and AI panel states.
- Included functionality for managing brush presets, text editing, and selection transformations.

feat: Add utility functions for image and file handling

- Developed `utils.rs` with stateless helper functions for color formatting, drawing icons, and cropping images.
- Implemented save dialog builders and error handling for file operations.
- Added flood fill functionality for composite RGBA pixels.

test: Add unit test for bitmap brush stamp functionality

- Created `bitmap_brush_stamp.rs` to verify the behavior of bitmap brush stamping in the engine.
- Ensured that the painted area matches expected dimensions and characteristics.

hcie-egui-app/crates/hcie-gui-egui/src/app/ai_config.rs

@@ -0,0 +1,60 @@
+//! AI chat and ComfyUI/vision configuration types.
+//!
+//! These small data-only structs describe the state used by the AI Assistant
+//! panel and the optional ComfyUI/vision backend. They are grouped here so the
+//! larger `ToolState` does not need to define them inline.
+
+/// A single chat message in the AI Assistant panel.
+#[derive(Clone, Debug, Default, serde::Serialize, serde::Deserialize)]
+pub struct AiChatMessage {
+    pub role: String,
+    pub content: String,
+}
+
+/// URL/model pair used by the built-in AI chat client.
+#[derive(Clone, Debug, Default, serde::Serialize, serde::Deserialize)]
+pub struct AiChatConfig {
+    pub url: String,
+    pub model: String,
+}
+
+/// Last known ComfyUI server status.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum ComfyStatus {
+    #[default]
+    Unknown,
+    Running,
+    Error,
+}
+
+/// ComfyUI server endpoint configuration.
+#[derive(Clone, Debug, Default, serde::Serialize, serde::Deserialize)]
+pub struct ComfyConfig {
+    pub url: String,
+}
+
+/// Which ComfyUI workflow variant is active.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum ComfyMode {
+    #[default]
+    Normal,
+    ObjectRemoval,
+}
+
+/// High-level vision/AI task selected in the UI.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum VisionTask {
+    #[default]
+    Segmentation,
+    BackgroundRemoval,
+    Inpainting,
+    SuperResolution,
+}
+
+/// Preferred execution backend for vision pipelines.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, serde::Serialize, serde::Deserialize)]
+pub enum VisionBackend {
+    #[default]
+    Cpu,
+    Gpu,
+}

hcie-egui-app/crates/hcie-gui-egui/src/app/document_state.rs

@@ -0,0 +1,130 @@
+//! Per-document runtime state.
+//!
+//! Each open image owns an `AppDocument` which wraps the engine instance, GPU
+//! texture handles, viewport state, and bookkeeping such as source path and
+//! modification status.
+
+use crate::app::theme::default_font_bytes;
+use crate::canvas::render::SelectionEdgeCache;
+use eframe::egui;
+use hcie_engine_api::Engine;
+
+/// Current high-level application mode.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum AppMode {
+    #[default]
+    Editor,
+    Viewer,
+}
+
+pub struct AppDocument {
+    pub engine: Engine,
+    pub composite_texture: Option<egui::TextureHandle>,
+    pub layer_textures: std::collections::HashMap<usize, egui::TextureHandle>,
+    pub composite_buffer: Vec<u8>,
+    pub zoom: f32,
+    pub name: String,
+    pub init_snapshot_needed: bool,
+    pub init_snapshot_at: Option<std::time::Instant>,
+    /// Original file path this document was loaded from, if any.
+    pub source_path: Option<std::path::PathBuf>,
+    /// Original format extension this document was loaded as, e.g. "psd" or "kra".
+    pub source_format: Option<String>,
+    /// Whether the document has been modified since it was last saved/loaded.
+    pub modified: bool,
+    pub history_brush_names: std::collections::HashMap<usize, String>,
+    /// Shared marching-ants edge cache for the selection overlay.
+    pub selection_edge_cache: SelectionEdgeCache,
+    /// Per-document pan offset for the canvas viewport.
+    /// Moved from ToolState to AppDocument so each document maintains its own
+    /// independent pan position, preventing cross-document interference.
+    pub pan_offset: egui::Vec2,
+    /// The last egui Context used to render/upload this document's GPU textures.
+    /// Used to detect when a panel is floated/docked (context change) and re-upload textures.
+    pub last_ctx: Option<egui::Context>,
+}
+
+impl AppDocument {
+    pub fn new(name: &str, w: u32, h: u32) -> Self {
+        let mut engine = Engine::new(w, h);
+        engine.set_modified(false);
+        if let Some((font_name, font_bytes)) = default_font_bytes() {
+            let _ = engine.load_font(&font_name, &font_bytes);
+        }
+        engine.pre_tile_all_layers();
+        Self {
+            engine,
+            composite_texture: None,
+            layer_textures: std::collections::HashMap::new(),
+            composite_buffer: vec![],
+            zoom: 1.0,
+            name: name.to_string(),
+            init_snapshot_needed: false,
+            init_snapshot_at: None,
+            source_path: None,
+            source_format: None,
+            modified: false,
+            history_brush_names: std::collections::HashMap::new(),
+            selection_edge_cache: SelectionEdgeCache::default(),
+            pan_offset: egui::Vec2::ZERO,
+            last_ctx: None,
+        }
+    }
+
+    pub fn record_history_description(&mut self, desc: String) {
+        let current = self.engine.history_current();
+        if current >= 0 {
+            let idx = current as usize;
+            self.history_brush_names.retain(|&k, _| k <= idx);
+            self.history_brush_names.insert(idx, desc);
+        }
+    }
+
+    pub fn save_file_name(&self) -> String {
+        if let Some(path) = &self.source_path {
+            path.file_name()
+                .map(|n| n.to_string_lossy().to_string())
+                .unwrap_or_else(|| format!("{}.png", self.name))
+        } else {
+            format!("{}.png", self.name)
+        }
+    }
+
+    pub fn save_file_stem(&self) -> String {
+        if let Some(path) = &self.source_path {
+            path.file_stem()
+                .map(|n| n.to_string_lossy().to_string())
+                .unwrap_or_else(|| self.name.clone())
+        } else {
+            self.name.clone()
+        }
+    }
+
+    pub fn set_source_path(&mut self, path: std::path::PathBuf, format: &str) {
+        self.source_path = Some(path);
+        self.source_format = Some(format.to_lowercase());
+        self.modified = false;
+    }
+
+    pub fn mark_modified(&mut self) {
+        self.modified = true;
+    }
+
+    pub fn try_init_snapshot(&mut self) {
+        if !self.init_snapshot_needed {
+            return;
+        }
+        if let Some(at) = self.init_snapshot_at {
+            if std::time::Instant::now() < at {
+                return;
+            }
+        }
+        if self.engine.get_layer_count() == 0 {
+            self.engine.add_layer("Background");
+        }
+        log::debug!("[try_init_snapshot] Warming up engine allocations and Rayon threadpool");
+        self.engine.pre_tile_all_layers();
+        self.init_snapshot_needed = false;
+        self.init_snapshot_at = None;
+    }
+}

hcie-egui-app/crates/hcie-gui-egui/src/app/settings.rs

@@ -0,0 +1,50 @@
+//! Persistent application settings and dock profiles.
+//!
+//! This module keeps user preferences such as theme, recent files, saved dock
+//! layouts, and viewer-mode state. It is intentionally separate from runtime
+//! tool state so it can be serialized independently.
+
+use egui_panel_adapter::ThemePreset;
+
+/// A single entry in the recent-files list.
+#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
+pub struct RecentFileEntry {
+    pub path: String,
+    pub name: String,
+}
+
+/// A saved dock layout including panel widths and pinned tabs.
+#[derive(Clone, Debug, serde::Serialize, serde::Deserialize)]
+pub struct DockProfile {
+    pub name: String,
+    pub dock_state_json: String,
+    pub left_col1_w: f32,
+    pub left_col2_w: f32,
+    pub right_col1_w: f32,
+    pub right_col2_w: f32,
+    pub last_window_width: f32,
+    pub pinned_panels: Vec<String>,
+}
+
+/// Top-level persistent settings serialized by eframe on exit.
+#[derive(Clone, Debug, Default, serde::Serialize, serde::Deserialize)]
+pub struct Settings {
+    pub theme: ThemePreset,
+    /// When `true`, the operating system draws its own window decorations.
+    /// The custom title bar is always rendered regardless of this value,
+    /// so the out-of-box experience uses the unified custom bar.
+    #[serde(default = "default_show_native_decorations")]
+    pub show_native_decorations: bool,
+    pub debug_mode: bool,
+    #[serde(default)]
+    pub recent_files: Vec<RecentFileEntry>,
+    #[serde(default)]
+    pub dock_profiles: Vec<DockProfile>,
+    /// Last directory used in Viewer mode, for cross-session persistence.
+    #[serde(default)]
+    pub viewer_last_dir: Option<String>,
+}
+
+fn default_show_native_decorations() -> bool {
+    false
+}

hcie-egui-app/crates/hcie-gui-egui/src/app/theme.rs

@@ -0,0 +1,250 @@
+//! Visual theme and font setup for the egui GUI.
+//!
+//! This module centralizes:
+//!   - System font discovery and registration.
+//!   - Application of the shared `ThemeColors` / `ThemePreset` into egui visuals.
+//!   - Helper to retrieve raw default font bytes for the engine text renderer.
+
+use eframe::egui;
+
+pub use egui_panel_adapter::{ThemeColors, ThemePreset};
+
+/// Register discovered system fonts into the egui context.
+///
+/// On Linux/macOS/Windows the first available system sans-serif font is loaded
+/// and used as the default proportional font family so the UI matches the OS.
+pub fn setup_custom_fonts(ctx: &egui::Context) {
+    let mut fonts = egui::FontDefinitions::default();
+
+    for (name, data) in discover_system_fonts() {
+        fonts
+            .font_data
+            .insert(name.clone(), std::sync::Arc::new(data));
+        // Override the default proportional font family so UI uses OS font
+        fonts
+            .families
+            .entry(egui::FontFamily::Proportional)
+            .or_default()
+            .insert(0, name);
+    }
+
+    ctx.set_fonts(fonts);
+}
+
+/// Load the first available system font and return its (file_name, bytes).
+/// This is shared between egui font setup and engine text-renderer registration.
+#[cfg(target_os = "linux")]
+fn discover_system_fonts() -> Vec<(String, egui::FontData)> {
+    let mut res = Vec::new();
+    let paths = [
+        "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf",
+        "/usr/share/fonts/truetype/liberation/LiberationSans-Regular.ttf",
+        "/usr/share/fonts/truetype/noto/NotoSans-Regular.ttf",
+        "/usr/share/fonts/truetype/freefont/FreeSans.ttf",
+    ];
+    for path in &paths {
+        if let Ok(bytes) = std::fs::read(path) {
+            let name = path.rsplit('/').next().unwrap_or("system").to_string();
+            res.push((name, egui::FontData::from_owned(bytes)));
+            break;
+        }
+    }
+    res
+}
+
+#[cfg(target_os = "macos")]
+fn discover_system_fonts() -> Vec<(String, egui::FontData)> {
+    let mut res = Vec::new();
+    let paths = [
+        "/System/Library/Fonts/Helvetica.ttc",
+        "/System/Library/Fonts/HelveticaNeue.ttc",
+        "/Library/Fonts/Arial.ttf",
+    ];
+    for path in &paths {
+        if let Ok(bytes) = std::fs::read(path) {
+            let name = path.rsplit('/').next().unwrap_or("system").to_string();
+            res.push((name, egui::FontData::from_owned(bytes)));
+            break;
+        }
+    }
+    res
+}
+
+#[cfg(target_os = "windows")]
+fn discover_system_fonts() -> Vec<(String, egui::FontData)> {
+    let mut res = Vec::new();
+    let paths = [
+        "C:\\Windows\\Fonts\\arial.ttf",
+        "C:\\Windows\\Fonts\\segoeui.ttf",
+        "C:\\Windows\\Fonts\\calibri.ttf",
+    ];
+    for path in &paths {
+        if let Ok(bytes) = std::fs::read(path) {
+            let name = path.rsplit('\\').next().unwrap_or("system").to_string();
+            res.push((name, egui::FontData::from_owned(bytes)));
+            break;
+        }
+    }
+    res
+}
+
+/// Returns the raw bytes and a normalized name for the first available system font.
+/// Used to seed the engine's `TextRenderer` with a default font on startup.
+pub fn default_font_bytes() -> Option<(String, Vec<u8>)> {
+    let paths: &[(&str, &str)] = &[
+        #[cfg(target_os = "linux")]
+        (
+            "/usr/share/fonts/truetype/dejavu/DejaVuSans.ttf",
+            "DejaVuSans.ttf",
+        ),
+        #[cfg(target_os = "linux")]
+        (
+            "/usr/share/fonts/truetype/liberation/LiberationSans-Regular.ttf",
+            "LiberationSans-Regular.ttf",
+        ),
+        #[cfg(target_os = "linux")]
+        (
+            "/usr/share/fonts/truetype/noto/NotoSans-Regular.ttf",
+            "NotoSans-Regular.ttf",
+        ),
+        #[cfg(target_os = "linux")]
+        (
+            "/usr/share/fonts/truetype/freefont/FreeSans.ttf",
+            "FreeSans.ttf",
+        ),
+        #[cfg(target_os = "macos")]
+        ("/System/Library/Fonts/Helvetica.ttc", "Helvetica.ttc"),
+        #[cfg(target_os = "macos")]
+        (
+            "/System/Library/Fonts/HelveticaNeue.ttc",
+            "HelveticaNeue.ttc",
+        ),
+        #[cfg(target_os = "macos")]
+        ("/Library/Fonts/Arial.ttf", "Arial.ttf"),
+        #[cfg(target_os = "windows")]
+        ("C:\\Windows\\Fonts\\arial.ttf", "arial.ttf"),
+        #[cfg(target_os = "windows")]
+        ("C:\\Windows\\Fonts\\segoeui.ttf", "segoeui.ttf"),
+        #[cfg(target_os = "windows")]
+        ("C:\\Windows\\Fonts\\calibri.ttf", "calibri.ttf"),
+    ];
+    for (path, name) in paths {
+        if let Ok(bytes) = std::fs::read(path) {
+            return Some(((*name).to_string(), bytes));
+        }
+    }
+    None
+}
+
+/// **Purpose:** Applies the system-wide visual theme configurations to the egui context.
+///
+/// **Logic & Workflow:**
+/// 1. Fetches the active `ThemeColors` palette based on the chosen preset.
+/// 2. Configures default Light/Dark visuals on the egui Context.
+/// 3. Propagates all color tokens directly into `style.visuals` structures so that
+///    non-interactive panel elements, idle buttons, hover highlights, active states,
+///    scrollbars, text selections, and dropdowns inherit the theme.
+/// 4. Harmonizes component padding, margins, and roundings for a clean desktop design.
+///
+/// **Arguments:**
+/// * `ctx`: The reference to the active egui Context.
+/// * `theme`: The selected ThemePreset enum.
+pub fn apply_theme(ctx: &egui::Context, theme: ThemePreset) {
+    let colors = ThemeColors::get(theme);
+    let is_light = colors.is_light;
+    ctx.set_visuals(if is_light {
+        egui::Visuals::light()
+    } else {
+        egui::Visuals::dark()
+    });
+    ctx.style_mut(|style| {
+        // ── Rounded corners (consistent 4px everywhere) ──
+        let r4 = egui::CornerRadius::same(4);
+        style.visuals.widgets.noninteractive.corner_radius = r4;
+        style.visuals.widgets.inactive.corner_radius = r4;
+        style.visuals.widgets.hovered.corner_radius = r4;
+        style.visuals.widgets.active.corner_radius = r4;
+        style.visuals.widgets.open.corner_radius = r4;
+
+        // ── Window / popup rounding ──
+        style.visuals.window_corner_radius = egui::CornerRadius::same(6);
+        style.visuals.menu_corner_radius = egui::CornerRadius::same(6);
+
+        // ── Core surface fills (3-tier elevation) ──
+        style.visuals.window_fill = colors.bg_elevated;
+        style.visuals.panel_fill = colors.bg_panel;
+        style.visuals.window_stroke = egui::Stroke::new(1.0, colors.border_high);
+        style.visuals.extreme_bg_color = colors.bg_recessed;
+        style.visuals.faint_bg_color = colors.bg_hover.gamma_multiply(0.4);
+
+        // ── Noninteractive widgets (labels, static elements) ──
+        style.visuals.widgets.noninteractive.bg_fill = colors.bg_panel;
+        style.visuals.widgets.noninteractive.bg_stroke = egui::Stroke::new(1.0, colors.border_low);
+        style.visuals.widgets.noninteractive.fg_stroke =
+            egui::Stroke::new(1.0, colors.text_secondary);
+
+        // ── Inactive widgets (idle buttons, slider tracks, checkboxes) ──
+        style.visuals.widgets.inactive.bg_fill = colors.bg_dark_depth;
+        style.visuals.widgets.inactive.bg_stroke = egui::Stroke::new(1.0, colors.border_high);
+        style.visuals.widgets.inactive.fg_stroke = egui::Stroke::new(1.0, colors.text_primary);
+
+        // ── Hover states ──
+        style.visuals.widgets.hovered.bg_fill = colors.bg_hover;
+        style.visuals.widgets.hovered.bg_stroke = egui::Stroke::new(1.0, colors.accent);
+        style.visuals.widgets.hovered.fg_stroke = egui::Stroke::new(1.2, colors.text_primary);
+
+        // ── Active highlights (clicked buttons, active controls) ──
+        style.visuals.widgets.active.bg_fill = colors.accent;
+        style.visuals.widgets.active.bg_stroke = egui::Stroke::new(1.0, colors.accent);
+        style.visuals.widgets.active.fg_stroke = egui::Stroke::new(1.2, colors.text_primary);
+
+        // ── Open menus and popups ──
+        style.visuals.widgets.open.bg_fill = colors.bg_elevated;
+        style.visuals.widgets.open.bg_stroke = egui::Stroke::new(1.0, colors.border_high);
+
+        // ── Text selection & highlights ──
+        style.visuals.selection.bg_fill = colors.accent.gamma_multiply(0.3);
+        style.visuals.selection.stroke = egui::Stroke::new(1.0, colors.accent);
+
+        // ── Slider trailing fill (shows value range) ──
+        style.visuals.slider_trailing_fill = true;
+
+        // ── Popup shadow for depth ──
+        style.visuals.popup_shadow = egui::Shadow {
+            offset: [0, 4],
+            blur: 16,
+            spread: 0,
+            color: egui::Color32::from_black_alpha(if is_light { 18 } else { 60 }),
+        };
+
+        // ── Font sizes matching Qt 12px default ──
+        style.text_styles.insert(
+            egui::TextStyle::Body,
+            egui::FontId::proportional(12.0),
+        );
+        style.text_styles.insert(
+            egui::TextStyle::Button,
+            egui::FontId::proportional(12.0),
+        );
+        style.text_styles.insert(
+            egui::TextStyle::Small,
+            egui::FontId::proportional(11.0),
+        );
+        style.text_styles.insert(
+            egui::TextStyle::Heading,
+            egui::FontId::proportional(13.5),
+        );
+        style.text_styles.insert(
+            egui::TextStyle::Monospace,
+            egui::FontId::proportional(11.5),
+        );
+
+        // ── Harmonized layout parameters (8px grid) ──
+        style.spacing.item_spacing = egui::vec2(4.0, 4.0);
+        style.spacing.window_margin = egui::Margin::same(6);
+        style.spacing.button_padding = egui::vec2(6.0, 3.0);
+        style.spacing.indent = 12.0;
+        style.spacing.slider_width = 140.0;
+        style.spacing.interact_size = egui::vec2(28.0, 22.0);
+    });
+}

hcie-egui-app/crates/hcie-gui-egui/src/app/tool_state.rs

@@ -0,0 +1,459 @@
+//! Runtime tool, selection, and transform state.
+//!
+//! This module contains the interactive state that changes every frame: the
+//! active tool, color, brush settings, selection operation, text edit, vector
+//! transform, tablet input, and AI/ComfyUI panel state. It is deliberately
+//! separate from persistent `Settings`.
+
+use crate::app::ai_config::{
+    AiChatConfig, AiChatMessage, ComfyConfig, ComfyMode, ComfyStatus, VisionBackend, VisionTask,
+};
+use crate::app::settings::Settings;
+use crate::app::shell::tablet_input::TabletState;
+use crate::app::TOOL_SLOTS;
+use eframe::egui;
+use hcie_engine_api::{Tool, ToolConfigs, VectorEditHandle, VectorShape};
+use std::sync::Arc;
+
+#[derive(Clone)]
+pub struct ToolState {
+    pub active_tool: Tool,
+    pub primary_color: [u8; 4],
+    pub secondary_color: [u8; 4],
+    pub recent_colors: Vec<[u8; 4]>,
+    pub tool_configs: ToolConfigs,
+    pub current_pressure: f32,
+    pub pan_offset: egui::Vec2,
+    pub cursor_canvas_pos: Option<(u32, u32)>,
+    pub selection_rect: Option<[u32; 4]>,
+    /// VisionSelect drag rectangle in canvas coordinates, used for bbox segmentation.
+    pub vision_select_rect: Option<[u32; 4]>,
+    pub is_drawing: bool,
+    pub drag_start_pos: Option<(u32, u32)>,
+    pub last_draw_pos: Option<(u32, u32)>,
+    pub brush_accumulated_dist: f32,
+    pub lasso_points: Vec<(u32, u32)>,
+    pub smart_patch_points: Vec<(u32, u32)>,
+    pub text_edit: TextEditState,
+    pub selected_vector_shape: Option<usize>,
+    pub vector_shapes_snapshot: Option<Vec<VectorShape>>,
+    pub vector_is_new_creation: bool,
+    pub vector_edit_handle: VectorEditHandle,
+    pub vector_drag_last: Option<egui::Pos2>,
+    pub settings: Settings,
+    pub pinned_panels: std::collections::HashSet<String>,
+    /// Set of utility panels that the user has collapsed with the custom
+    /// collapse chevron on the active tab.
+    pub collapsed_panels: std::collections::HashSet<crate::app::dock::HciePane>,
+    pub ai_panel_tab: usize,
+    pub ai_chat_thinking: bool,
+    pub is_ai_processing: bool,
+    pub ai_actions_busy: bool,
+    pub ai_chat_history: Vec<AiChatMessage>,
+    pub ai_chat_config: AiChatConfig,
+    pub ai_chat_models: Vec<String>,
+    pub ai_send_canvas: bool,
+    pub ai_vision_review: bool,
+    pub ai_chat_show_reasoning: bool,
+    pub ai_chat_max_turns: u32,
+    pub ai_chat_buffer: String,
+    pub comfy_status: ComfyStatus,
+    pub comfy_config: ComfyConfig,
+    pub comfy_mode: ComfyMode,
+    pub brush_presets: Vec<hcie_engine_api::BrushPreset>,
+    pub active_brush_preset_id: String,
+    pub comfy_models: Vec<String>,
+    pub selected_model: String,
+    pub vision_task: VisionTask,
+    pub vision_sam_model_path: String,
+    pub vision_birefnet_model_path: String,
+    pub vision_migan_model_path: String,
+    pub vision_backend: VisionBackend,
+    pub script_editor: egui_panel_script::ScriptEditor,
+    pub ai_script_generator: egui_panel_ai_script::AiScriptGenerator,
+    pub vector_shapes_expanded: bool,
+    pub tool_scroll_offset: f32,
+    pub transform: Option<SelectionTransform>,
+    pub transform_drag_handle: TransformHandle,
+    /// Shared tablet/stylus state updated by winit/evdev and read each frame.
+    pub tablet_state: Arc<std::sync::Mutex<TabletState>>,
+    pub active_slot: usize,
+    pub slot_last_used: Vec<usize>,
+    pub active_popup_slot: Option<usize>,
+    pub popup_anchor_pos: Option<egui::Pos2>,
+    pub popup_close_request: bool,
+    pub slot_press_start: Option<(usize, std::time::Instant)>,
+    pub popup_opened_via_drag: bool,
+    /// If true, the left toolbox is rendered as a two-column wide strip.
+    pub toolbox_two_column: bool,
+    /// When set, the active layer is locked to this id while a destructive
+    /// preview dialog (e.g. Adjustments) is open. The Layers panel refuses to
+    /// switch the active layer while this is set, and the app re-asserts the
+    /// locked layer every frame so programmatic layer changes (shortcuts,
+    /// canvas auto-create, etc.) cannot move the filter target to another
+    /// layer. Cleared when the owning dialog closes.
+    pub locked_active_layer: Option<u64>,
+    /// Whether the recent colors popup/expand section is shown.
+    pub show_recent_popup: bool,
+    /// Pending name input used by the brush editor "New Preset" action.
+    pub pending_brush_preset_name: Option<String>,
+    /// Whether the brush editor updates the canvas brush preview live.
+    pub brush_editor_instant_preview: bool,
+    pub is_resizing_brush: bool,
+    pub brush_resize_start_size: f32,
+    pub brush_resize_start_pos: Option<egui::Pos2>,
+    /// Cached brush preset thumbnail textures keyed by preset ID.
+    /// Generated once when ABR/KPP files are loaded or on explicit refresh.
+    pub brush_thumbnail_cache: std::collections::HashMap<String, egui::TextureHandle>,
+    /// When true, all cached thumbnails are regenerated on the next frame.
+    pub brush_thumbnail_dirty: bool,
+}
+
+impl Default for ToolState {
+    fn default() -> Self {
+        let mut pinned = std::collections::HashSet::new();
+        pinned.insert("Tools".to_string());
+        pinned.insert("Brushes & Tips".to_string());
+        pinned.insert("Color Palette".to_string());
+        pinned.insert("Layers".to_string());
+        Self {
+            active_tool: Tool::Brush,
+            primary_color: [0, 0, 0, 255],
+            secondary_color: [255, 255, 255, 255],
+            recent_colors: vec![],
+            tool_configs: ToolConfigs::default(),
+            current_pressure: 1.0,
+            pan_offset: egui::Vec2::ZERO,
+            cursor_canvas_pos: None,
+            selection_rect: None,
+            vision_select_rect: None,
+            is_drawing: false,
+            drag_start_pos: None,
+            last_draw_pos: None,
+            brush_accumulated_dist: 0.0,
+            lasso_points: vec![],
+            smart_patch_points: vec![],
+            text_edit: TextEditState::default(),
+            selected_vector_shape: None,
+            vector_shapes_snapshot: None,
+            vector_is_new_creation: false,
+            vector_edit_handle: VectorEditHandle::None,
+            vector_drag_last: None,
+            settings: Settings::default(),
+            pinned_panels: pinned,
+            collapsed_panels: std::collections::HashSet::new(),
+            ai_panel_tab: 0,
+            ai_chat_thinking: false,
+            is_ai_processing: false,
+            ai_actions_busy: false,
+            ai_chat_history: vec![],
+            ai_chat_config: AiChatConfig {
+                url: "http://127.0.0.1:8188".into(),
+                model: "flux".into(),
+            },
+            ai_chat_models: vec![],
+            ai_send_canvas: false,
+            ai_vision_review: false,
+            ai_chat_show_reasoning: false,
+            ai_chat_max_turns: 10,
+            ai_chat_buffer: String::new(),
+            comfy_status: ComfyStatus::Unknown,
+            comfy_config: ComfyConfig {
+                url: "http://127.0.0.1:8188".into(),
+            },
+            comfy_mode: ComfyMode::Normal,
+            brush_presets: hcie_engine_api::BrushPreset::all_defaults(),
+            active_brush_preset_id: "basic_round".to_string(),
+            comfy_models: vec![],
+            selected_model: String::new(),
+            vision_task: VisionTask::default(),
+            vision_sam_model_path: "models/sam/MobileSAM-F16.gguf".to_string(),
+            vision_birefnet_model_path: "models/birefnet/BiRefNet-lite-F16.gguf".to_string(),
+            vision_migan_model_path: "models/migan/MIGAN-512-places2-F16.gguf".to_string(),
+            vision_backend: VisionBackend::default(),
+            script_editor: egui_panel_script::ScriptEditor::new(),
+            ai_script_generator: egui_panel_ai_script::AiScriptGenerator::new(),
+            vector_shapes_expanded: false,
+            tool_scroll_offset: 0.0,
+            transform: None,
+            transform_drag_handle: TransformHandle::None,
+            tablet_state: Arc::new(std::sync::Mutex::new(TabletState::new())),
+            active_slot: TOOL_SLOTS
+                .iter()
+                .position(|s| s.contains(&Tool::Brush))
+                .unwrap_or(0),
+            slot_last_used: {
+                let mut v = vec![0usize; TOOL_SLOTS.len()];
+                if let Some(si) = TOOL_SLOTS.iter().position(|s| s.contains(&Tool::Brush)) {
+                    if let Some(li) = TOOL_SLOTS[si].iter().position(|&t| t == Tool::Brush) {
+                        v[si] = li;
+                    }
+                }
+                v
+            },
+            active_popup_slot: None,
+            popup_anchor_pos: None,
+            popup_close_request: false,
+            slot_press_start: None,
+            popup_opened_via_drag: false,
+            toolbox_two_column: false,
+            locked_active_layer: None,
+            show_recent_popup: false,
+            pending_brush_preset_name: None,
+            brush_editor_instant_preview: true,
+            is_resizing_brush: false,
+            brush_resize_start_size: 10.0,
+            brush_resize_start_pos: None,
+            brush_thumbnail_cache: std::collections::HashMap::new(),
+            brush_thumbnail_dirty: true,
+        }
+    }
+}
+
+impl ToolState {
+    pub fn active_size(&self) -> f32 {
+        match self.active_tool {
+            Tool::Pen => self.tool_configs.pen.size,
+            Tool::Brush => self.tool_configs.brush.size,
+            Tool::Eraser => self.tool_configs.eraser.size,
+            Tool::Spray => self.tool_configs.spray.radius,
+            _ => 10.0,
+        }
+    }
+
+    pub fn set_active_size(&mut self, size: f32) {
+        match self.active_tool {
+            Tool::Pen => self.tool_configs.pen.size = size,
+            Tool::Brush => self.tool_configs.brush.size = size,
+            Tool::Eraser => self.tool_configs.eraser.size = size,
+            Tool::Spray => self.tool_configs.spray.radius = size,
+            _ => {}
+        }
+    }
+
+    pub fn active_size_mut(&mut self) -> &mut f32 {
+        match self.active_tool {
+            Tool::Pen => &mut self.tool_configs.pen.size,
+            Tool::Brush => &mut self.tool_configs.brush.size,
+            Tool::Eraser => &mut self.tool_configs.eraser.size,
+            Tool::Spray => &mut self.tool_configs.spray.radius,
+            _ => &mut self.tool_configs.pen.size,
+        }
+    }
+
+    pub fn active_opacity(&self) -> f32 {
+        match self.active_tool {
+            Tool::Pen => self.tool_configs.pen.opacity,
+            Tool::Brush => self.tool_configs.brush.opacity,
+            Tool::Eraser => self.tool_configs.eraser.opacity,
+            Tool::Spray => self.tool_configs.spray.opacity,
+            _ => 1.0,
+        }
+    }
+
+    pub fn set_active_opacity(&mut self, opacity: f32) {
+        match self.active_tool {
+            Tool::Pen => self.tool_configs.pen.opacity = opacity,
+            Tool::Brush => self.tool_configs.brush.opacity = opacity,
+            Tool::Eraser => self.tool_configs.eraser.opacity = opacity,
+            Tool::Spray => self.tool_configs.spray.opacity = opacity,
+            _ => {}
+        }
+    }
+
+    pub fn brush_dirty_radius(&self) -> f32 {
+        self.active_size() * 0.5 + 2.0
+    }
+
+    pub fn slot_for_tool(tool: Tool) -> Option<usize> {
+        TOOL_SLOTS.iter().position(|slot| slot.contains(&tool))
+    }
+
+    pub fn set_active_tool_from_slot(&mut self, tool: Tool) {
+        if let Some(slot_idx) = Self::slot_for_tool(tool) {
+            self.active_slot = slot_idx;
+            if let Some(local_idx) = TOOL_SLOTS[slot_idx].iter().position(|&t| t == tool) {
+                self.slot_last_used[slot_idx] = local_idx;
+            }
+        }
+        self.active_tool = tool;
+    }
+}
+
+/// Selection morphological operations shown in the context menu / dialog.
+pub enum SelectionOp {
+    Grow(u32),
+    Shrink(u32),
+    Feather(u32),
+    Erode(u32),
+    Fade(u32),
+}
+
+/// Live text editing state used by the inline canvas text tool.
+///
+/// When the user clicks on the canvas with the Text tool, a draft text
+/// layer is created and its properties are kept here. All changes in the
+/// Properties panel or in the on-canvas text edit are applied to the draft
+/// layer immediately so the user sees a live preview. The edits are only
+/// committed when Accept is pressed; Cancel discards a newly created draft
+/// layer, or reverts an existing text layer to the snapshot stored in
+/// `original_text` and its companion `original_*` fields.
+#[derive(Clone)]
+pub struct TextEditState {
+    pub active: bool,
+    pub layer_id: u64,
+    pub draft_text: String,
+    pub draft_font: String,
+    pub draft_size: f32,
+    pub draft_color: [u8; 4],
+    pub draft_angle: f32,
+    pub draft_alignment: hcie_engine_api::TextAlignment,
+    pub draft_orientation: hcie_engine_api::TextOrientation,
+    pub canvas_x: u32,
+    pub canvas_y: u32,
+    pub accepted: bool,
+    pub cancelled: bool,
+    /// If true, the layer was created by the current inline edit session and
+    /// should be deleted on Cancel. If false, Cancel reverts to `original_*`.
+    pub is_new: bool,
+    /// Snapshot of the layer's text and properties taken when an existing text
+    /// layer enters edit mode. Used to restore the layer on Cancel.
+    pub original_text: String,
+    pub original_font: String,
+    pub original_size: f32,
+    pub original_color: [u8; 4],
+    pub original_angle: f32,
+    pub original_alignment: hcie_engine_api::TextAlignment,
+    pub original_orientation: hcie_engine_api::TextOrientation,
+}
+
+impl Default for TextEditState {
+    fn default() -> Self {
+        Self {
+            active: false,
+            layer_id: 0,
+            draft_text: String::new(),
+            draft_font: "default".to_string(),
+            draft_size: 24.0,
+            draft_color: [0, 0, 0, 255],
+            draft_angle: 0.0,
+            draft_alignment: hcie_engine_api::TextAlignment::Left,
+            draft_orientation: hcie_engine_api::TextOrientation::Horizontal,
+            canvas_x: 0,
+            canvas_y: 0,
+            accepted: false,
+            cancelled: false,
+            is_new: true,
+            original_text: String::new(),
+            original_font: "default".to_string(),
+            original_size: 24.0,
+            original_color: [0, 0, 0, 255],
+            original_angle: 0.0,
+            original_alignment: hcie_engine_api::TextAlignment::Left,
+            original_orientation: hcie_engine_api::TextOrientation::Horizontal,
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum TransformHandle {
+    #[default]
+    None,
+    Move,
+    TopLeft,
+    TopRight,
+    BottomRight,
+    BottomLeft,
+    Top,
+    Bottom,
+    Left,
+    Right,
+}
+
+#[derive(Clone)]
+pub struct SelectionTransform {
+    pub pixels: Vec<u8>,
+    pub width: u32,
+    pub height: u32,
+    pub pos: egui::Vec2,
+    pub size: egui::Vec2,
+}
+
+impl SelectionTransform {
+    pub fn from_engine(engine: &hcie_engine_api::Engine, mask: &[u8], w: u32, h: u32) -> Self {
+        if mask.is_empty() || w == 0 || h == 0 {
+            return Self {
+                pixels: vec![],
+                width: 0,
+                height: 0,
+                pos: egui::Vec2::ZERO,
+                size: egui::Vec2::ZERO,
+            };
+        }
+        let mut min_x = w;
+        let mut min_y = h;
+        let mut max_x = 0u32;
+        let mut max_y = 0u32;
+        let mut has_selection = false;
+
+        for y in 0..h {
+            for x in 0..w {
+                if mask[(y * w + x) as usize] > 0 {
+                    min_x = min_x.min(x);
+                    min_y = min_y.min(y);
+                    max_x = max_x.max(x);
+                    max_y = max_y.max(y);
+                    has_selection = true;
+                }
+            }
+        }
+
+        if !has_selection {
+            return Self {
+                pixels: vec![],
+                width: 0,
+                height: 0,
+                pos: egui::Vec2::ZERO,
+                size: egui::Vec2::ZERO,
+            };
+        }
+
+        let bw = max_x - min_x + 1;
+        let bh = max_y - min_y + 1;
+        let mut pixels = vec![0u8; (bw * bh * 4) as usize];
+
+        let layer_pixels = engine.get_active_layer_pixels().unwrap_or_default();
+        let layer_w = engine.canvas_width() as usize;
+        let w_usize = w as usize;
+        let bw_usize = bw as usize;
+        let bh_usize = bh as usize;
+        let min_x_usize = min_x as usize;
+        let min_y_usize = min_y as usize;
+
+        for y in 0..bh_usize {
+            for x in 0..bw_usize {
+                let src_x = min_x_usize + x;
+                let src_y = min_y_usize + y;
+                let mask_idx = src_y * w_usize + src_x;
+                if mask_idx < mask.len() && mask[mask_idx] > 0 {
+                    let px_idx = (src_y * layer_w + src_x) * 4;
+                    if px_idx + 3 < layer_pixels.len() {
+                        let dst_idx = (y * bw_usize + x) * 4;
+                        pixels[dst_idx] = layer_pixels[px_idx];
+                        pixels[dst_idx + 1] = layer_pixels[px_idx + 1];
+                        pixels[dst_idx + 2] = layer_pixels[px_idx + 2];
+                        pixels[dst_idx + 3] = layer_pixels[px_idx + 3];
+                    }
+                }
+            }
+        }
+
+        Self {
+            pixels,
+            width: bw,
+            height: bh,
+            pos: egui::Vec2::new(min_x as f32, min_y as f32),
+            size: egui::Vec2::new(bw as f32, bh as f32),
+        }
+    }
+}

hcie-egui-app/crates/hcie-gui-egui/src/app/tools/brushes_panel.rs

@@ -4,6 +4,11 @@ use eframe::egui;
 use hcie_engine_api::brush::{BrushStyle, BrushTip};
 use hcie_engine_api::BrushPreset;
 use hcie_engine_api::Tool;
+use std::collections::hash_map::DefaultHasher;
+use std::hash::{Hash, Hasher};
+
+const THUMB_W: u32 = 140;
+const THUMB_H: u32 = 64;
 
 fn matches_category(active_cat: &str, preset_cat: &str) -> bool {
     if active_cat == "All" {
@@ -12,6 +17,9 @@ fn matches_category(active_cat: &str, preset_cat: &str) -> bool {
     if active_cat == "Custom" {
         return preset_cat.eq_ignore_ascii_case("Custom");
     }
+    if active_cat == "Imported" {
+        return preset_cat.eq_ignore_ascii_case("Imported") || preset_cat.eq_ignore_ascii_case("Imported (ABR)");
+    }
     let mapped: &[&str] = match active_cat {
         "Drawing" => &["Basic", "Sketch"],
         "Painting" => &["Paint", "Ink"],
@@ -21,12 +29,158 @@ fn matches_category(active_cat: &str, preset_cat: &str) -> bool {
     mapped.iter().any(|c| c.eq_ignore_ascii_case(preset_cat))
 }
 
-/// Draw a gorgeous custom procedural preview of a brush style inside a rect.
+fn preset_thumb_hash(preset: &BrushPreset) -> u64 {
+    let mut hasher = DefaultHasher::new();
+    preset.style.hash(&mut hasher);
+    preset.tip.size.to_bits().hash(&mut hasher);
+    preset.tip.hardness.to_bits().hash(&mut hasher);
+    preset.tip.opacity.to_bits().hash(&mut hasher);
+    preset.tip.roundness.to_bits().hash(&mut hasher);
+    preset.tip.spacing.to_bits().hash(&mut hasher);
+    preset.tip.bitmap_w.hash(&mut hasher);
+    preset.tip.bitmap_h.hash(&mut hasher);
+    if !preset.tip.bitmap_pixels.is_empty() {
+        let step = (preset.tip.bitmap_pixels.len() / 64).max(1);
+        for (_i, &v) in preset.tip.bitmap_pixels.iter().enumerate().step_by(step) {
+            v.hash(&mut hasher);
+        }
+    }
+    hasher.finish()
+}
+
+fn render_thumb_to_texture(
+    ctx: &egui::Context,
+    preset: &BrushPreset,
+) -> egui::TextureHandle {
+    let w = THUMB_W as usize;
+    let h = THUMB_H as usize;
+    let mut pixels = vec![0u8; w * h * 4];
+    render_thumb_into_rgba(preset, &mut pixels, w, h);
+    let image = egui::ColorImage::from_rgba_unmultiplied([w, h], &pixels);
+    ctx.load_texture(format!("thumb_{}", preset.id), image, egui::TextureOptions::LINEAR)
+}
+
+fn render_thumb_into_rgba(preset: &BrushPreset, buf: &mut [u8], w: usize, h: usize) {
+    let style = preset.style;
+    let gray: [u8; 4] = [200, 200, 200, 255];
+    let x0f = 16.0_f32;
+    let x1f = (w as f32) - 16.0;
+    let y_mid = (h as f32) * 0.5;
+    let n = 45;
+    let mut pts: Vec<(f32, f32, f32)> = Vec::with_capacity(n + 1);
+    for i in 0..=n {
+        let t = i as f32 / n as f32;
+        let x = x0f + t * (x1f - x0f);
+        let angle = t * std::f32::consts::TAU * 1.25;
+        let taper = (t * (1.0 - t) * 4.0).powf(1.1);
+        let y = y_mid + angle.sin() * (h as f32 * 0.22) * taper;
+        pts.push((x, y, t));
+    }
+    match style {
+        BrushStyle::Bitmap => {
+            if preset.tip.bitmap_pixels.is_empty() || preset.tip.bitmap_w == 0 || preset.tip.bitmap_h == 0 {
+                return;
+            }
+            let bw = preset.tip.bitmap_w as f32;
+            let bh = preset.tip.bitmap_h as f32;
+            let scale = (w as f32 / bw).min(h as f32 / bh);
+            let draw_w = bw * scale;
+            let draw_h = bh * scale;
+            let ox = ((w as f32) - draw_w) * 0.5;
+            let oy = ((h as f32) - draw_h) * 0.5;
+            let px = scale.max(1.0);
+            let mut sy = 0u32;
+            let mut py = 0.0;
+            while sy < preset.tip.bitmap_h {
+                let mut sx = 0u32;
+                let mut ppx = 0.0;
+                while sx < preset.tip.bitmap_w {
+                    let mask = preset.tip.bitmap_pixels[(sy * preset.tip.bitmap_w + sx) as usize] as f32 / 255.0;
+                    if mask > 0.01 {
+                        let a = (mask * 255.0).round() as u8;
+                        let rx = (ox + ppx).round() as i32;
+                        let ry = (oy + py).round() as i32;
+                        let rw = px.ceil() as i32;
+                        let rh = px.ceil() as i32;
+                        for dy in 0..rh {
+                            for dx in 0..rw {
+                                let px_i = rx + dx;
+                                let py_i = ry + dy;
+                                if px_i >= 0 && py_i >= 0 && (px_i as usize) < w && (py_i as usize) < h {
+                                    let idx = ((py_i as usize) * w + (px_i as usize)) * 4;
+                                    buf[idx] = gray[0];
+                                    buf[idx + 1] = gray[1];
+                                    buf[idx + 2] = gray[2];
+                                    buf[idx + 3] = a;
+                                }
+                            }
+                        }
+                    }
+                    ppx += px;
+                    sx += 1;
+                }
+                py += px;
+                sy += 1;
+            }
+            return;
+        }
+        _ => {}
+    }
+    let thickness_base = match style {
+        BrushStyle::Square => 2.0,
+        BrushStyle::Pen => 1.0,
+        BrushStyle::Pencil => 1.0,
+        BrushStyle::Airbrush => 6.0,
+        BrushStyle::Oil => 6.5,
+        BrushStyle::Glow => 2.5,
+        BrushStyle::InkPen => 0.9,
+        BrushStyle::Wood => 3.8,
+        _ => 2.0,
+    };
+    for i in 0..n {
+        let (x1, y1, t1) = pts[i];
+        let (x2, y2, _) = pts[i + 1];
+        let p = (t1 * std::f32::consts::PI).sin();
+        let thick = thickness_base * p;
+        let steps_i = (thick * 2.0).ceil() as i32;
+        for step in 0..steps_i.max(1) {
+            let frac = step as f32 / (steps_i.max(1) as f32) - 0.5;
+            let nx = -(y2 - y1);
+            let ny = x2 - x1;
+            let len = (nx * nx + ny * ny).sqrt().max(0.001);
+            let off_x = nx / len * frac * thick;
+            let off_y = ny / len * frac * thick;
+            let sx_f = x1 + off_x;
+            let sy_f = y1 + off_y;
+            let ex_f = x2 + off_x;
+            let ey_f = y2 + off_y;
+            let dist_x = (ex_f - sx_f).abs();
+            let dist_y = (ey_f - sy_f).abs();
+            let steps = (dist_x.max(dist_y).ceil() as i32).max(1);
+            for s in 0..=steps {
+                let t = s as f32 / steps as f32;
+                let px_f = sx_f + (ex_f - sx_f) * t;
+                let py_f = sy_f + (ey_f - sy_f) * t;
+                let r = px_f.round() as i32;
+                let c = py_f.round() as i32;
+                if r >= 0 && c >= 0 && (r as usize) < w && (c as usize) < h {
+                    let idx = ((c as usize) * w + (r as usize)) * 4;
+                    buf[idx] = gray[0];
+                    buf[idx + 1] = gray[1];
+                    buf[idx + 2] = gray[2];
+                    buf[idx + 3] = gray[3];
+                }
+            }
+        }
+    }
+}
+
 pub fn draw_brush_preview(
     painter: &egui::Painter,
     rect: egui::Rect,
     style: hcie_engine_api::tools::BrushStyle,
-    color: egui::Color32,
+    _color: egui::Color32,
+    tip: Option<&BrushTip>,
 ) {
     let _width = rect.width();
     let height = rect.height();
@@ -39,7 +193,6 @@ pub fn draw_brush_preview(
     for i in 0..=n_points {
         let t = i as f32 / n_points as f32;
         let x = x0 + t * (x1 - x0);
-        // Tapered wave formula for S-curve
         let angle = t * std::f32::consts::TAU * 1.25;
         let sine = angle.sin();
         let taper = (t * (1.0 - t) * 4.0).powf(1.1);
@@ -47,12 +200,12 @@ pub fn draw_brush_preview(
         points.push((x, y, t));
     }
 
+    let color = egui::Color32::from_gray(200);
     match style {
         hcie_engine_api::tools::BrushStyle::Default
         | hcie_engine_api::tools::BrushStyle::Round
         | hcie_engine_api::tools::BrushStyle::HardRound
         | hcie_engine_api::tools::BrushStyle::SoftRound => {
-            // Smooth tapered round path
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -65,7 +218,6 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Square => {
-            // Squared-off strokes with flat ends
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -78,7 +230,6 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Noise => {
-            // Grainy jittery stroke
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -92,27 +243,17 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Texture => {
-            // Rough dotted texture stroke
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.15 {
-                    continue;
-                }
+                if p < 0.15 { continue; }
                 let alpha = 0.3 + 0.5 * (x * 23.0).sin().abs();
-                painter.circle_filled(
-                    egui::pos2(x, y),
-                    1.2 + 2.0 * p,
-                    color.linear_multiply(alpha),
-                );
+                painter.circle_filled(egui::pos2(x, y), 1.2 + 2.0 * p, color.linear_multiply(alpha));
             }
         }
         hcie_engine_api::tools::BrushStyle::Spray => {
-            // Scattered spray particles
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.05 {
-                    continue;
-                }
+                if p < 0.05 { continue; }
                 for s in 0..6 {
                     let angle = (x * 9.0 + s as f32 * 1.1).sin() * std::f32::consts::TAU;
                     let dist = (y * 11.0 + s as f32 * 1.7).cos().abs() * 8.0 * p;
@@ -123,28 +264,24 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Pen => {
-            // Crisp thin pen line
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
                 let p = (t1 * std::f32::consts::PI).sin();
-                let thickness = 1.0 + 1.2 * p;
                 painter.line_segment(
                     [egui::pos2(x1, y1), egui::pos2(x2, y2)],
-                    egui::Stroke::new(thickness, color),
+                    egui::Stroke::new(1.0 + 1.2 * p, color),
                 );
             }
         }
         hcie_engine_api::tools::BrushStyle::Airbrush => {
-            // Soft transparent wide overlay
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
                 let p = (t1 * std::f32::consts::PI).sin();
-                let base_color = color.linear_multiply(0.08);
                 painter.line_segment(
                     [egui::pos2(x1, y1), egui::pos2(x2, y2)],
-                    egui::Stroke::new(14.0 * p, base_color),
+                    egui::Stroke::new(14.0 * p, color.linear_multiply(0.08)),
                 );
                 painter.line_segment(
                     [egui::pos2(x1, y1), egui::pos2(x2, y2)],
@@ -153,43 +290,33 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Pencil => {
-            // Thin scratchy slightly noisy line
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
                 let p = (t1 * std::f32::consts::PI).sin();
-                let noise1 = (x1 * 13.0).sin() * 0.35;
-                let noise2 = (x2 * 13.0).sin() * 0.35;
+                let n1 = (x1 * 13.0).sin() * 0.35;
+                let n2 = (x2 * 13.0).sin() * 0.35;
                 painter.line_segment(
-                    [egui::pos2(x1, y1 + noise1), egui::pos2(x2, y2 + noise2)],
+                    [egui::pos2(x1, y1 + n1), egui::pos2(x2, y2 + n2)],
                     egui::Stroke::new(1.0 + 0.8 * p, color.linear_multiply(0.9)),
                 );
             }
         }
         hcie_engine_api::tools::BrushStyle::Charcoal => {
-            // Rough scratchy textured points
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.1 {
-                    continue;
-                }
-                let steps = 4;
-                for s in 0..steps {
+                if p < 0.1 { continue; }
+                for s in 0..4 {
                     let angle = (x * 7.3 + s as f32).sin() * std::f32::consts::TAU;
                     let dist = (x * 11.2 + s as f32).cos().abs() * 3.5 * p;
                     let px = x + angle.cos() * dist;
                     let py = y + angle.sin() * dist;
                     let alpha = 0.25 + 0.55 * (x * 19.3).sin().abs();
-                    painter.circle_filled(
-                        egui::pos2(px, py),
-                        1.0 + 1.2 * p,
-                        color.linear_multiply(alpha),
-                    );
+                    painter.circle_filled(egui::pos2(px, py), 1.0 + 1.2 * p, color.linear_multiply(alpha));
                 }
             }
         }
         hcie_engine_api::tools::BrushStyle::Watercolor => {
-            // Bleeding watercolor blobs with wet edges
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
                 let r = 8.0 * p + 1.5;
@@ -198,12 +325,10 @@ pub fn draw_brush_preview(
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
                 let r = 8.0 * p + 1.5;
-                let edge_color = color.linear_multiply(0.12);
-                painter.circle_stroke(egui::pos2(x, y), r, egui::Stroke::new(0.8, edge_color));
+                painter.circle_stroke(egui::pos2(x, y), r, egui::Stroke::new(0.8, color.linear_multiply(0.12)));
             }
         }
         hcie_engine_api::tools::BrushStyle::Calligraphy => {
-            // Slanted ribbon lines
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
                 let w = 4.2 * p;
@@ -214,165 +339,61 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Leaf => {
-            // Scattered oval leaf shapes with color variation, shadow, and stem
             for (i, &(x, y, t)) in points.iter().enumerate() {
-                if i % 4 != 0 {
-                    continue;
-                }
+                if i % 4 != 0 { continue; }
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.15 {
-                    continue;
-                }
-                // Vary color per leaf (darker/lighter)
+                if p < 0.15 { continue; }
                 let shade = 0.35 + 0.55 * (i as f32 * 0.7).sin().abs();
-                let leaf_color = color.linear_multiply(shade);
-                let leaf_dark = color.linear_multiply(shade * 0.55);
-                // Leaf size with slight variation
                 let size = 1.8 + 2.0 * p;
-                // Slight horizontal offset for natural scatter
                 let lx = x + (i as f32 * 1.3).sin() * 1.5;
-                // Draw leaf as small vertical oval (pill shape)
                 let leaf_rect = egui::Rect::from_center_size(
-                    egui::pos2(lx, y),
-                    egui::vec2(size * 0.45, size * 1.1),
+                    egui::pos2(lx, y), egui::vec2(size * 0.45, size * 1.1),
                 );
-                // Shadow below and slightly to the right
-                let shadow_rect = leaf_rect.translate(egui::vec2(0.4, 0.6));
                 painter.rect_filled(
-                    shadow_rect,
+                    leaf_rect.translate(egui::vec2(0.4, 0.6)),
                     egui::CornerRadius::same((size * 0.22).round() as u8),
-                    leaf_dark.linear_multiply(0.35),
+                    color.linear_multiply(shade * 0.55 * 0.35),
                 );
-                // Leaf body
                 painter.rect_filled(
                     leaf_rect,
                     egui::CornerRadius::same((size * 0.22).round() as u8),
-                    leaf_color,
-                );
-                // Top-half highlight
-                let hl_rect = egui::Rect::from_min_max(
-                    leaf_rect.left_top(),
-                    egui::pos2(leaf_rect.right(), leaf_rect.center().y),
-                );
-                painter.rect_filled(
-                    hl_rect,
-                    egui::CornerRadius::same(1),
-                    leaf_color.linear_multiply(1.25),
-                );
-                // Thin outline
-                painter.rect_stroke(
-                    leaf_rect,
-                    egui::CornerRadius::same((size * 0.22).round() as u8),
-                    egui::Stroke::new(0.4, leaf_dark),
-                    egui::StrokeKind::Outside,
-                );
-                // Tiny stem at bottom
-                let stem_top = egui::pos2(lx, leaf_rect.bottom());
-                let stem_bot = egui::pos2(lx + 0.5, leaf_rect.bottom() + size * 0.5);
-                painter.line_segment(
-                    [stem_top, stem_bot],
-                    egui::Stroke::new(0.5, leaf_dark.linear_multiply(0.6)),
+                    color.linear_multiply(shade),
                 );
             }
         }
         hcie_engine_api::tools::BrushStyle::Rock => {
-            // Irregular rounded rocks with bottom shadow and top highlight
             for (i, &(x, y, t)) in points.iter().enumerate() {
-                if i % 2 != 0 {
-                    continue;
-                }
+                if i % 2 != 0 { continue; }
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.1 {
-                    continue;
-                }
-                // Rock dimensions with variation
-                let rw = 3.0 + 3.5 * p * (0.7 + 0.3 * (i as f32 * 1.3).sin().abs());
-                let rh = 2.0 + 2.5 * p * (0.7 + 0.3 * (i as f32 * 0.9).cos().abs());
-                let rounding = 1.5 + 2.5 * (i as f32 * 0.5).sin().abs();
+                if p < 0.1 { continue; }
+                let rw = 3.0 + 3.5 * p;
+                let rh = 2.0 + 2.5 * p;
                 let shade = 0.40 + 0.40 * (i as f32 * 0.7).sin().abs();
-                let rock_color = color.linear_multiply(shade);
-                let rock_dark = color.linear_multiply(shade * 0.55);
                 let rx = x + (i as f32).sin() * 1.5;
                 let ry = y + (i as f32 * 0.7).cos() * 1.0;
-                let rock_rect =
-                    egui::Rect::from_center_size(egui::pos2(rx, ry), egui::vec2(rw, rh));
-                // Bottom shadow (lower half of rock, darker)
-                let shadow_rect = egui::Rect::from_min_max(
-                    egui::pos2(rock_rect.left(), rock_rect.center().y - rh * 0.1),
-                    rock_rect.right_bottom(),
-                );
-                painter.rect_filled(shadow_rect, egui::CornerRadius::same(1), rock_dark);
-                // Rock body
+                let rock_rect = egui::Rect::from_center_size(egui::pos2(rx, ry), egui::vec2(rw, rh));
                 painter.rect_filled(
-                    rock_rect,
-                    egui::CornerRadius::same(rounding.round() as u8),
-                    rock_color,
-                );
-                // Dark outline
-                painter.rect_stroke(
-                    rock_rect,
-                    egui::CornerRadius::same(rounding.round() as u8),
-                    egui::Stroke::new(0.6, rock_dark.linear_multiply(0.8)),
-                    egui::StrokeKind::Outside,
-                );
-                // Top-left highlight
-                let hl_rect = egui::Rect::from_min_max(
-                    rock_rect.left_top(),
-                    egui::pos2(rock_rect.left() + rw * 0.4, rock_rect.top() + rh * 0.35),
-                );
-                painter.rect_filled(
-                    hl_rect,
-                    egui::CornerRadius::same(1),
-                    rock_color.linear_multiply(1.3),
+                    rock_rect, egui::CornerRadius::same(2), color.linear_multiply(shade),
                 );
             }
         }
         hcie_engine_api::tools::BrushStyle::Meadow => {
-            // Curved grass blades drawn as thin line segments, with color variation and shadow
             for (i, &(x, y, t)) in points.iter().enumerate() {
-                if i % 2 != 0 {
-                    continue;
-                }
+                if i % 2 != 0 { continue; }
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.1 {
-                    continue;
-                }
-                // 2-3 blades per point for density
-                let blade_count = 2 + (i % 2);
-                for b in 0..blade_count {
-                    let offset_x = (i as f32 * 3.7 + b as f32 * 5.1).sin() * 2.5;
-                    let bx = x + offset_x;
-                    let blade_h =
-                        (4.0 + 5.0 * p) * (0.7 + 0.3 * (i as f32 * 1.1 + b as f32).sin().abs());
-                    let wind = (bx * 5.0 + i as f32 * 0.5).sin() * 2.0;
-                    let shade = 0.35 + 0.45 * (b as f32 * 0.7 + p).sin().abs();
-                    let blade_color = color.linear_multiply(shade);
-                    let blade_dark = color.linear_multiply(shade * 0.5);
-                    // Curved blade as 2 line segments (base→mid→tip)
-                    let base = egui::pos2(bx, y);
-                    let mid = egui::pos2(bx + wind * 0.4, y - blade_h * 0.5);
-                    let tip = egui::pos2(bx + wind, y - blade_h);
-                    // Shadow at base
-                    painter.circle_filled(base, 0.8, blade_dark.linear_multiply(0.5));
-                    // Lower half (thicker stem)
-                    painter.line_segment([base, mid], egui::Stroke::new(1.0, blade_color));
-                    // Upper half (thin tip)
-                    painter.line_segment(
-                        [mid, tip],
-                        egui::Stroke::new(0.5, blade_color.linear_multiply(0.9)),
-                    );
-                    // Thin highlight on left side
-                    let hl_start = egui::pos2(base.x - 0.3, base.y - 0.3);
-                    let hl_mid = egui::pos2(mid.x - 0.3, mid.y - 0.3);
-                    painter.line_segment(
-                        [hl_start, hl_mid],
-                        egui::Stroke::new(0.2, blade_color.linear_multiply(1.3)),
-                    );
-                }
+                if p < 0.1 { continue; }
+                let blade_h = 4.0 + 5.0 * p;
+                let wind = (x * 5.0 + i as f32 * 0.5).sin() * 2.0;
+                let shade = 0.35 + 0.45 * (i as f32 * 0.7 + p).sin().abs();
+                let blade_color = color.linear_multiply(shade);
+                let base = egui::pos2(x, y);
+                let mid = egui::pos2(x + wind * 0.4, y - blade_h * 0.5);
+                let tip = egui::pos2(x + wind, y - blade_h);
+                painter.line_segment([base, mid], egui::Stroke::new(1.0, blade_color));
+                painter.line_segment([mid, tip], egui::Stroke::new(0.5, blade_color.linear_multiply(0.9)));
             }
         }
         hcie_engine_api::tools::BrushStyle::Wood => {
-            // Wood grain overlay
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -381,15 +402,9 @@ pub fn draw_brush_preview(
                     [egui::pos2(x1, y1), egui::pos2(x2, y2)],
                     egui::Stroke::new(3.8 * p, color.linear_multiply(0.75)),
                 );
-                let offset = 4.2 * p;
-                painter.line_segment(
-                    [egui::pos2(x1, y1 + offset), egui::pos2(x2, y2 + offset)],
-                    egui::Stroke::new(1.0 * p, color.linear_multiply(0.45)),
-                );
             }
         }
         hcie_engine_api::tools::BrushStyle::Oil => {
-            // Thick oily strokes with sheen highlights
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -405,7 +420,6 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Glow => {
-            // Glowing neon core
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -425,24 +439,14 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Clouds => {
-            // Dreamy circular puffy blobs
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
                 let r = 8.5 * p;
-                painter.circle_filled(
-                    egui::pos2(x, y),
-                    r,
-                    egui::Color32::WHITE.linear_multiply(0.16),
-                );
-                painter.circle_filled(
-                    egui::pos2(x, y - 2.0),
-                    r * 0.8,
-                    egui::Color32::WHITE.linear_multiply(0.24),
-                );
+                painter.circle_filled(egui::pos2(x, y), r, egui::Color32::WHITE.linear_multiply(0.16));
+                painter.circle_filled(egui::pos2(x, y - 2.0), r * 0.8, egui::Color32::WHITE.linear_multiply(0.24));
             }
         }
         hcie_engine_api::tools::BrushStyle::Tree => {
-            // Branch structures
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -452,19 +456,15 @@ pub fn draw_brush_preview(
                     egui::Stroke::new(3.0 * p + 1.0, color),
                 );
                 if i == n_points / 3 || i == 2 * n_points / 3 {
-                    let branch_dir = if i == n_points / 3 { -1.0 } else { 1.0 };
+                    let d = if i == n_points / 3 { -1.0 } else { 1.0 };
                     painter.line_segment(
-                        [
-                            egui::pos2(x1, y1),
-                            egui::pos2(x1 + 6.0, y1 + branch_dir * 8.0),
-                        ],
+                        [egui::pos2(x1, y1), egui::pos2(x1 + 6.0, y1 + d * 8.0)],
                         egui::Stroke::new(1.5 * p, color),
                     );
                 }
             }
         }
         hcie_engine_api::tools::BrushStyle::Bristle => {
-            // Separated bristle hair strands
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -479,42 +479,28 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Crayon => {
-            // Textured crayon look
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.1 {
-                    continue;
-                }
+                if p < 0.1 { continue; }
                 for s in 0..3 {
                     let jx = (x * 17.5 + s as f32 * 5.0).sin() * 2.0 * p;
                     let jy = (y * 23.4 + s as f32 * 9.0).cos() * 2.0 * p;
-                    painter.circle_filled(
-                        egui::pos2(x + jx, y + jy),
-                        1.2 * p,
-                        color.linear_multiply(0.48),
-                    );
+                    painter.circle_filled(egui::pos2(x + jx, y + jy), 1.2 * p, color.linear_multiply(0.48));
                 }
             }
         }
         hcie_engine_api::tools::BrushStyle::Hatch => {
-            // Cross hatches
             for (i, &(x, y, t)) in points.iter().enumerate() {
-                if i % 4 != 0 {
-                    continue;
-                }
+                if i % 4 != 0 { continue; }
                 let p = (t * std::f32::consts::PI).sin();
-                let size = 4.2 * p;
+                let sz = 4.2 * p;
                 painter.line_segment(
-                    [
-                        egui::pos2(x - size, y - size),
-                        egui::pos2(x + size, y + size),
-                    ],
+                    [egui::pos2(x - sz, y - sz), egui::pos2(x + sz, y + sz)],
                     egui::Stroke::new(0.9, color),
                 );
             }
         }
         hcie_engine_api::tools::BrushStyle::WetPaint => {
-            // Wet paint drops
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -524,16 +510,11 @@ pub fn draw_brush_preview(
                     egui::Stroke::new(6.0 * p, color),
                 );
                 if i % 10 == 0 && i > 0 {
-                    painter.circle_filled(
-                        egui::pos2(x1, y1 + 4.2 * p),
-                        2.2 * p,
-                        color.linear_multiply(0.78),
-                    );
+                    painter.circle_filled(egui::pos2(x1, y1 + 4.2 * p), 2.2 * p, color.linear_multiply(0.78));
                 }
             }
         }
         hcie_engine_api::tools::BrushStyle::InkPen => {
-            // Crisp ink pen
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -545,18 +526,17 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Marker => {
-            // Angled wide highlighting tape
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
                 let w = 5.2 * p;
-                let marker_col = color.linear_multiply(0.42);
-                let p1 = egui::pos2(x - w, y + w * 1.8);
-                let p2 = egui::pos2(x + w, y - w * 1.8);
-                painter.line_segment([p1, p2], egui::Stroke::new(3.8, marker_col));
+                let mc = color.linear_multiply(0.42);
+                painter.line_segment(
+                    [egui::pos2(x - w, y + w * 1.8), egui::pos2(x + w, y - w * 1.8)],
+                    egui::Stroke::new(3.8, mc),
+                );
             }
         }
         hcie_engine_api::tools::BrushStyle::Sketch => {
-            // Sketch overlapping lines
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -574,46 +554,27 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Star => {
-            // Tiny star sparkles
             for (i, &(x, y, t)) in points.iter().enumerate() {
-                if i % 6 != 0 {
-                    continue;
-                }
+                if i % 6 != 0 { continue; }
                 let p = (t * std::f32::consts::PI).sin();
                 let r = 4.2 * p;
-                if r < 1.0 {
-                    continue;
-                }
-                painter.line_segment(
-                    [egui::pos2(x - r, y), egui::pos2(x + r, y)],
-                    egui::Stroke::new(1.1, color),
-                );
-                painter.line_segment(
-                    [egui::pos2(x, y - r), egui::pos2(x, y + r)],
-                    egui::Stroke::new(1.1, color),
-                );
+                if r < 1.0 { continue; }
+                painter.line_segment([egui::pos2(x - r, y), egui::pos2(x + r, y)], egui::Stroke::new(1.1, color));
+                painter.line_segment([egui::pos2(x, y - r), egui::pos2(x, y + r)], egui::Stroke::new(1.1, color));
             }
         }
         hcie_engine_api::tools::BrushStyle::Dirt => {
-            // Dusty dirt speckles
             for &(x, y, t) in &points {
                 let p = (t * std::f32::consts::PI).sin();
-                if p < 0.1 {
-                    continue;
-                }
+                if p < 0.1 { continue; }
                 for s in 0..2 {
                     let ox = (x * 47.3 + s as f32 * 11.0).sin() * 6.0 * p;
                     let oy = (y * 53.2 + s as f32 * 17.0).cos() * 6.0 * p;
-                    painter.circle_filled(
-                        egui::pos2(x + ox, y + oy),
-                        0.7,
-                        color.linear_multiply(0.4),
-                    );
+                    painter.circle_filled(egui::pos2(x + ox, y + oy), 0.7, color.linear_multiply(0.4));
                 }
             }
         }
         hcie_engine_api::tools::BrushStyle::Mixer | hcie_engine_api::tools::BrushStyle::Blender => {
-            // Dual gradient smudge ribbon
             for i in 0..n_points {
                 let (x1, y1, t1) = points[i];
                 let (x2, y2, _t2) = points[i + 1];
@@ -626,22 +587,69 @@ pub fn draw_brush_preview(
             }
         }
         hcie_engine_api::tools::BrushStyle::Bitmap => {
-            // Show a simple stroke preview for imported bitmap brushes
-            for i in 0..n_points {
-                let (x1, y1, t1) = points[i];
-                let (x2, y2, _t2) = points[i + 1];
-                let p = (t1 * std::f32::consts::PI).sin();
-                let thickness = 1.0 + 5.0 * p;
-                painter.line_segment(
-                    [egui::pos2(x1, y1), egui::pos2(x2, y2)],
-                    egui::Stroke::new(thickness, color),
-                );
+            if let Some(tip) = tip {
+                render_bitmap_thumbnail(painter, rect, tip, color);
+            } else {
+                for i in 0..n_points {
+                    let (x1, y1, t1) = points[i];
+                    let (x2, y2, _t2) = points[i + 1];
+                    let p = (t1 * std::f32::consts::PI).sin();
+                    let thickness = 1.0 + 5.0 * p;
+                    painter.line_segment(
+                        [egui::pos2(x1, y1), egui::pos2(x2, y2)],
+                        egui::Stroke::new(thickness, color),
+                    );
+                }
             }
         }
     }
 }
 
-/// Convert standard lib-level `hcie_engine_api::BrushStyle` to tool-level `hcie_engine_api::tools::BrushStyle`.
+fn render_bitmap_thumbnail(
+    painter: &egui::Painter,
+    rect: egui::Rect,
+    tip: &BrushTip,
+    color: egui::Color32,
+) {
+    if tip.bitmap_pixels.is_empty() || tip.bitmap_w == 0 || tip.bitmap_h == 0 {
+        return;
+    }
+    let bw = tip.bitmap_w as f32;
+    let bh = tip.bitmap_h as f32;
+    let scale = (rect.width() / bw).min(rect.height() / bh);
+    let draw_w = bw * scale;
+    let draw_h = bh * scale;
+    let offset_x = (rect.width() - draw_w) * 0.5;
+    let offset_y = (rect.height() - draw_h) * 0.5;
+
+    let pixel_size = scale.max(1.0);
+    let mut shapes = Vec::new();
+    let mut y = 0.0;
+    let mut sy = 0u32;
+    while sy < tip.bitmap_h {
+        let mut x = 0.0;
+        let mut sx = 0u32;
+        while sx < tip.bitmap_w {
+            let mask_val = tip.bitmap_pixels[(sy * tip.bitmap_w + sx) as usize] as f32 / 255.0;
+            if mask_val > 0.01 {
+                let a = (mask_val * color.a() as f32).round() as u8;
+                let c = egui::Color32::from_rgba_unmultiplied(color.r(), color.g(), color.b(), a);
+                let p = rect.min + egui::vec2(offset_x + x, offset_y + y);
+                shapes.push(egui::Shape::rect_filled(
+                    egui::Rect::from_min_size(p, egui::vec2(pixel_size, pixel_size)),
+                    0.0,
+                    c,
+                ));
+            }
+            x += pixel_size;
+            sx += 1;
+        }
+        y += pixel_size;
+        sy += 1;
+    }
+    painter.add(egui::Shape::Vec(shapes));
+}
+
 pub fn to_tools_style(style: hcie_engine_api::BrushStyle) -> hcie_engine_api::tools::BrushStyle {
     match style {
         hcie_engine_api::BrushStyle::Round
@@ -1006,8 +1014,8 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
     ui.add_space(6.0);
 
     // 2. Category Tab Filters - Oval Pills with 12px rounding
-    let categories = ["All", "Drawing", "Painting", "Effects", "Custom"];
-    let category_map = |cat: &str| -> Vec<&'static str> {
+    let categories = ["All", "Drawing", "Painting", "Effects", "Custom", "Imported"];
+    let _category_map = |cat: &str| -> Vec<&'static str> {
         match cat {
             "Drawing" => vec!["Basic", "Sketch"],
             "Painting" => vec!["Paint", "Ink"],
@@ -1068,6 +1076,18 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
             app.show_brush_editor = true;
             app.brush_editor_tab = 0;
         }
+        let refresh_btn = ui.add(
+            egui::Button::new(
+                egui::RichText::new("Refresh")
+                    .size(10.0)
+                    .color(colors.text_secondary),
+            )
+            .fill(egui::Color32::TRANSPARENT),
+        );
+        if refresh_btn.clicked() {
+            state.brush_thumbnail_cache.clear();
+            state.brush_thumbnail_dirty = true;
+        }
     });
 
     // 4. Segmented View Toggle Control Block (Unified with flat inner borders and outer rounded corners)
@@ -1238,12 +1258,20 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
                             egui::Stroke::new(0.5, colors.border_low),
                             egui::StrokeKind::Outside,
                         );
-                        draw_brush_preview(
-                            painter,
-                            preview_rect,
-                            to_tools_style(map_brush_style(preset.style)),
-                            primary_srgba,
-                        );
+                        let h = preset_thumb_hash(preset);
+                        let cache_key = format!("{}.{}", preset.id, h);
+                        if state.brush_thumbnail_dirty || !state.brush_thumbnail_cache.contains_key(&cache_key) {
+                            let tex = render_thumb_to_texture(ui.ctx(), preset);
+                            state.brush_thumbnail_cache.insert(cache_key.clone(), tex);
+                        }
+                        if let Some(tex) = state.brush_thumbnail_cache.get(&cache_key) {
+                            painter.image(
+                                tex.id(),
+                                preview_rect,
+                                egui::Rect::from_min_max(egui::pos2(0.0, 0.0), egui::pos2(1.0, 1.0)),
+                                egui::Color32::WHITE,
+                            );
+                        }
 
                         // Swatch Label Details
                         let name_pos = rect.left_top() + egui::vec2(86.0, 8.0);
@@ -1411,12 +1439,20 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
                             egui::Color32::from_gray(28)
                         };
                         painter.rect_filled(preview_rect, egui::CornerRadius::same(2), bg_fill);
-                        draw_brush_preview(
-                            painter,
-                            preview_rect,
-                            to_tools_style(map_brush_style(preset.style)),
-                            primary_srgba,
-                        );
+                        let h = preset_thumb_hash(preset);
+                        let cache_key = format!("{}.{}", preset.id, h);
+                        if state.brush_thumbnail_dirty || !state.brush_thumbnail_cache.contains_key(&cache_key) {
+                            let tex = render_thumb_to_texture(ui.ctx(), preset);
+                            state.brush_thumbnail_cache.insert(cache_key.clone(), tex);
+                        }
+                        if let Some(tex) = state.brush_thumbnail_cache.get(&cache_key) {
+                            painter.image(
+                                tex.id(),
+                                preview_rect,
+                                egui::Rect::from_min_max(egui::pos2(0.0, 0.0), egui::pos2(1.0, 1.0)),
+                                egui::Color32::WHITE,
+                            );
+                        }
 
                         // Name
                         let name_pos =
@@ -1620,7 +1656,7 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
                                 egui::Stroke::new(0.5, colors.border_low),
                                 egui::StrokeKind::Outside,
                             );
-                            draw_brush_preview(painter, preview_rect, style, primary_srgba);
+                            draw_brush_preview(painter, preview_rect, style, primary_srgba, None);
 
                             let name_pos =
                                 egui::pos2(cell_rect.center().x, preview_rect.bottom() + 1.0);
@@ -1695,4 +1731,7 @@ pub fn show_brushes_ui(app: &mut HcieApp, ui: &mut egui::Ui) {
             }
         });
     });
+
+    // Clear dirty flag after all thumbnails have been rendered this frame
+    state.brush_thumbnail_dirty = false;
 }

hcie-egui-app/crates/hcie-gui-egui/src/app/utils.rs

@@ -0,0 +1,273 @@
+//! Small, stateless helper functions used across the app.
+//!
+//! This module gathers image/color utilities, file-dialog builders, save-error
+//! hints, and the flood-fill mask generator so the main app module stays
+//! focused on orchestration.
+
+use eframe::egui;
+
+/// Format an RGBA color as a `#RRGGBB` hex string (alpha is ignored).
+pub fn format_color(c: &[u8; 4]) -> String {
+    format!("#{:02x}{:02x}{:02x}", c[0], c[1], c[2])
+}
+
+/// **Purpose:** Draws a pixel-perfect, highly-refined minimalist pushpin vector icon.
+///
+/// **Logic & Workflow:**
+/// - If `pinned` is true, renders a vertical pushpin (cap, body, ridge, needle).
+/// - If `pinned` is false, renders a slanted 45-degree pushpin pointing down-left.
+pub fn draw_premium_pin(
+    painter: &egui::Painter,
+    center: egui::Pos2,
+    color: egui::Color32,
+    pinned: bool,
+) {
+    if pinned {
+        // Vertical pin (pinned state)
+        let cap_rect =
+            egui::Rect::from_center_size(center - egui::vec2(0.0, 4.0), egui::vec2(8.0, 1.5));
+        painter.rect_filled(cap_rect, 0.5, color);
+
+        let body_rect =
+            egui::Rect::from_center_size(center - egui::vec2(0.0, 1.0), egui::vec2(5.0, 4.5));
+        painter.rect_filled(body_rect, 0.5, color);
+
+        let ridge_rect =
+            egui::Rect::from_center_size(center + egui::vec2(0.0, 1.75), egui::vec2(7.0, 1.0));
+        painter.rect_filled(ridge_rect, 0.0, color);
+
+        let needle_rect =
+            egui::Rect::from_center_size(center + egui::vec2(0.0, 4.75), egui::vec2(1.2, 5.0));
+        painter.rect_filled(needle_rect, 0.0, color);
+    } else {
+        // Slanted pin (45 degrees pointing down-left, i.e., unpinned)
+        let dir = egui::vec2(-1.0, 1.0).normalized();
+        let ortho = egui::vec2(1.0, 1.0).normalized();
+
+        painter.line_segment(
+            [center + dir * 0.5, center + dir * 5.5],
+            egui::Stroke::new(1.3, color),
+        );
+
+        let ridge_c = center - dir * 0.75;
+        painter.line_segment(
+            [ridge_c - ortho * 3.0, ridge_c + ortho * 3.0],
+            egui::Stroke::new(1.2, color),
+        );
+
+        let body_c = ridge_c - dir * 2.0;
+        let p1 = body_c - ortho * 2.0 - dir * 1.5;
+        let p2 = body_c + ortho * 2.0 - dir * 1.5;
+        let p3 = body_c + ortho * 2.0 + dir * 1.5;
+        let p4 = body_c - ortho * 2.0 + dir * 1.5;
+        painter.add(egui::Shape::convex_polygon(
+            vec![p1, p2, p3, p4],
+            color,
+            egui::Stroke::NONE,
+        ));
+
+        let cap_c = ridge_c - dir * 4.25;
+        painter.line_segment(
+            [cap_c - ortho * 3.5, cap_c + ortho * 3.5],
+            egui::Stroke::new(1.5, color),
+        );
+    }
+}
+
+/// Crop an egui ColorImage to the given screen-space rectangle (rounded to pixels).
+pub fn crop_colorimage(img: &egui::ColorImage, rect: egui::Rect) -> Option<egui::ColorImage> {
+    let x0 = rect.min.x.max(0.0).round() as usize;
+    let y0 = rect.min.y.max(0.0).round() as usize;
+    let x1 = (rect.max.x.min(img.width() as f32)).round() as usize;
+    let y1 = (rect.max.y.min(img.height() as f32)).round() as usize;
+    let w = x1.saturating_sub(x0);
+    let h = y1.saturating_sub(y0);
+    if w == 0 || h == 0 {
+        return None;
+    }
+    let mut bytes = Vec::with_capacity(w * h * 4);
+    for y in y0..y1 {
+        for x in x0..x1 {
+            let c = img[(x, y)];
+            bytes.extend_from_slice(&c.to_array());
+        }
+    }
+    Some(egui::ColorImage::from_rgba_unmultiplied([w, h], &bytes))
+}
+
+pub fn save_colorimage(path: &std::path::Path, img: &egui::ColorImage) -> Result<(), String> {
+    let mut bytes: Vec<u8> = Vec::with_capacity(img.width() * img.height() * 4);
+    for c in img.pixels.iter() {
+        bytes.extend_from_slice(&c.to_array());
+    }
+    image::save_buffer(
+        path,
+        &bytes,
+        img.width() as u32,
+        img.height() as u32,
+        image::ColorType::Rgba8,
+    )
+    .map_err(|e| e.to_string())
+}
+
+/// Builds a fallback save path when the user-selected location cannot be written.
+///
+/// The suggestion tries the user's home directory first, then the system temp directory,
+/// preserving the original file stem and extension. This gives the user a concrete,
+/// writable alternative they can select instead of silently failing.
+pub fn suggest_alternative_path(original: &std::path::Path) -> std::path::PathBuf {
+    let stem = original
+        .file_stem()
+        .and_then(|s| s.to_str())
+        .unwrap_or("untitled");
+    let ext = original
+        .extension()
+        .and_then(|e| e.to_str())
+        .unwrap_or("hcie");
+    let file_name = format!("{}_copy.{}", stem, ext);
+
+    if let Some(home) = dirs::home_dir() {
+        let candidate = home.join(&file_name);
+        if candidate.parent().map(|p| p.exists()).unwrap_or(false) {
+            return candidate;
+        }
+    }
+
+    std::env::temp_dir().join(file_name)
+}
+
+/// Builds a Save/Export file dialog with the document's source format selected
+/// by default.
+///
+/// **Purpose:** Ensures the active file-type filter matches the document that
+/// is being saved (e.g. KRA for a Krita file). If the format is unknown, the
+/// helper still builds the dialog with HCIE Native listed first. An "All
+/// Supported Types" filter is appended at the end so the user can pick any
+/// supported format.
+///
+/// **Arguments:**
+/// * `default_format` - Lowercase extension to pre-select (`kra`, `hcie`, `png`, ...).
+/// * `file_stem` - Base name for the suggested file.
+/// * `is_export` - When `true`, appends `_export` to the file stem.
+pub fn build_save_dialog(default_format: &str, file_stem: &str, is_export: bool) -> rfd::FileDialog {
+    let suffix = if is_export { "_export" } else { "" };
+    let file_name = format!("{}{}.{}", file_stem, suffix, default_format);
+
+    let all_supported: &[&str] = &[
+        "png", "jpg", "jpeg", "webp", "bmp", "gif", "tiff", "tif", "avif", "ico", "pnm", "qoi",
+        "hdr", "dds", "tga", "exr", "psd", "kra", "hcie",
+    ];
+    let filters: Vec<(&str, &[&str])> = vec![
+        ("HCIE Native", &["hcie"]),
+        ("KRA", &["kra"]),
+        ("PSD", &["psd"]),
+        ("PNG", &["png"]),
+        ("JPEG", &["jpg", "jpeg"]),
+        ("WebP", &["webp"]),
+        ("AVIF", &["avif"]),
+        ("BMP", &["bmp"]),
+        ("GIF", &["gif"]),
+        ("TIFF", &["tiff", "tif"]),
+        ("ICO", &["ico"]),
+        ("PNM", &["pnm"]),
+        ("QOI", &["qoi"]),
+        ("HDR", &["hdr"]),
+        ("DDS", &["dds"]),
+        ("TGA", &["tga"]),
+        ("OpenEXR", &["exr"]),
+    ];
+
+    // Start with the format matching the document so it is the active filter.
+    let mut dialog = rfd::FileDialog::new().set_file_name(file_name);
+    for (name, exts) in &filters {
+        if exts.contains(&default_format) {
+            dialog = dialog.add_filter(*name, *exts);
+            break;
+        }
+    }
+    // Then add the remaining format filters.
+    for (name, exts) in &filters {
+        if !exts.contains(&default_format) {
+            dialog = dialog.add_filter(*name, *exts);
+        }
+    }
+    // Append a catch-all filter last.
+    dialog.add_filter("All Supported Types", all_supported)
+}
+
+/// Formats a short, actionable error message for the save/export failure dialog.
+///
+/// Detects common I/O errors (permission denied, not found, disk full) and adds a localized
+/// hint so the user understands why the operation failed and what to try next.
+pub fn format_save_error_hint(error: &str) -> &'static str {
+    let lower = error.to_lowercase();
+    if lower.contains("permission denied") || lower.contains("os error 13") {
+        "The selected folder is read-only or you don't have permission to write there."
+    } else if lower.contains("not found") || lower.contains("os error 2") {
+        "The parent folder no longer exists."
+    } else if lower.contains("no space") || lower.contains("os error 28") {
+        "The destination disk is full."
+    } else {
+        "Check that the destination folder exists and is writable."
+    }
+}
+
+/// Flood fill on composite RGBA pixels — works across all layers.
+/// Returns a `w*h` byte mask where 255 = selected, 0 = not selected.
+pub fn composite_flood_fill(
+    pixels: &[u8],
+    w: u32,
+    h: u32,
+    sx: u32,
+    sy: u32,
+    tolerance: i32,
+) -> Vec<u8> {
+    let (w, h) = (w as usize, h as usize);
+    let mut mask = vec![0u8; w * h];
+    if sx as usize >= w || sy as usize >= h || pixels.len() < w * h * 4 {
+        return mask;
+    }
+
+    let seed = (sy as usize * w + sx as usize) * 4;
+    let sr = pixels[seed] as i32;
+    let sg = pixels[seed + 1] as i32;
+    let sb = pixels[seed + 2] as i32;
+    let sa = pixels[seed + 3] as i32;
+
+    let mut queue = std::collections::VecDeque::new();
+    queue.push_back((sx as usize, sy as usize));
+    mask[sy as usize * w + sx as usize] = 255;
+    let mut count = 0usize;
+
+    while let Some((cx, cy)) = queue.pop_front() {
+        count += 1;
+        if count > 500_000 {
+            break;
+        }
+
+        for (dx, dy) in [(0i32, 1i32), (0, -1), (1, 0), (-1, 0)] {
+            let nx = cx as i32 + dx;
+            let ny = cy as i32 + dy;
+            if nx < 0 || nx >= w as i32 || ny < 0 || ny >= h as i32 {
+                continue;
+            }
+            let (nx, ny) = (nx as usize, ny as usize);
+            let ni = ny * w + nx;
+            if mask[ni] != 0 {
+                continue;
+            }
+
+            let pi = ni * 4;
+            let diff = (pixels[pi] as i32 - sr).abs()
+                + (pixels[pi + 1] as i32 - sg).abs()
+                + (pixels[pi + 2] as i32 - sb).abs()
+                + (pixels[pi + 3] as i32 - sa).abs();
+
+            if diff <= tolerance {
+                mask[ni] = 255;
+                queue.push_back((nx, ny));
+            }
+        }
+    }
+    mask
+}

hcie-egui-app/crates/hcie-gui-egui/src/brush_import.rs

@@ -3,6 +3,11 @@ use hcie_engine_api::brush::{BrushStyle, BrushTip};
 use hcie_engine_api::BrushPreset;
 use std::io::{Cursor, Read, Seek, SeekFrom};
 
+/// Parse an ABR brush file and return a list of `BrushPreset` entries.
+///
+/// The ABR format stores sampled bitmap brushes in a `samp` resource block and
+/// parametric/computed brushes in `computedB` markers. Brush names are extracted
+/// from the `desc` block (which contains `Nm  TEXT` tags) when available.
 pub fn import_abr(data: &[u8]) -> Vec<BrushPreset> {
     let mut presets = Vec::new();
     let mut cursor = Cursor::new(data);
@@ -26,6 +31,12 @@ pub fn import_abr(data: &[u8]) -> Vec<BrushPreset> {
                 if end > start && end <= data.len() {
                     presets.extend(harvest_sampled_brushes(&data[start..end], start));
                 }
+            } else if tag == "Brs2" || tag == "brst" {
+                let start = cursor.position() as usize;
+                let end = block_end as usize;
+                if end > start && end <= data.len() {
+                    presets.extend(harvest_brs2_sampled_brushes(&data[start..end], start));
+                }
             }
             pos = (block_end as usize + 1) & !1;
         } else {
@@ -34,6 +45,10 @@ pub fn import_abr(data: &[u8]) -> Vec<BrushPreset> {
     }
 
     presets.extend(harvest_computed_brushes(data));
+
+    let desc_names = extract_desc_block_names(data);
+    apply_desc_names(&mut presets, &desc_names);
+
     presets
 }
 
@@ -133,10 +148,16 @@ fn try_decode_and_scale(
     dst_w: u32,
     dst_h: u32,
 ) -> Option<Vec<u8>> {
-    let decoded = decode_packbits_lenient(data, src_w * src_h);
-    if decoded.len() != src_w * src_h {
+    // Some ABR files store the width as (right - left) but the PackBits stream
+    // contains one extra padding column/row. Accept decoded data that is at least
+    // src_w * src_h and truncate any surplus instead of rejecting the brush.
+    let mut decoded = decode_packbits_lenient(data, src_w * src_h);
+    if decoded.len() < src_w * src_h {
         return None;
     }
+    if decoded.len() > src_w * src_h {
+        decoded.truncate(src_w * src_h);
+    }
     if src_w as u32 == dst_w && src_h as u32 == dst_h {
         return Some(decoded);
     }
@@ -191,6 +212,86 @@ fn decode_packbits_lenient(data: &[u8], expected_size: usize) -> Vec<u8> {
     out
 }
 
+/// Heuristic extraction for sampled brushes embedded in a `Brs2` / `brst`
+/// resource block. Older ABR versions lay out the data as:
+///   [count u32] for each brush [l t r b i32] [depth?] [name pascal]
+///   [encoding byte?] [PackBits image data]
+/// This is intentionally lenient so we do not crash on partially unknown formats.
+fn harvest_brs2_sampled_brushes(data: &[u8], base_pos: usize) -> Vec<BrushPreset> {
+    let mut presets = Vec::new();
+    if data.len() < 4 {
+        return presets;
+    }
+    let count = u32::from_be_bytes([data[0], data[1], data[2], data[3]]) as usize;
+    if count == 0 || count > 1000 {
+        return presets;
+    }
+    let mut i = 4usize;
+    for _ in 0..count {
+        if i + 16 > data.len() {
+            break;
+        }
+        let l = i32::from_be_bytes([data[i], data[i + 1], data[i + 2], data[i + 3]]);
+        let t = i32::from_be_bytes([data[i + 4], data[i + 5], data[i + 6], data[i + 7]]);
+        let r = i32::from_be_bytes([data[i + 8], data[i + 9], data[i + 10], data[i + 11]]);
+        let b = i32::from_be_bytes([data[i + 12], data[i + 13], data[i + 14], data[i + 15]]);
+        i += 16;
+        let w = (r as i64 - l as i64).abs() as u32;
+        let h = (b as i64 - t as i64).abs() as u32;
+        if w == 0 || h == 0 || w > 10000 || h > 10000 {
+            continue;
+        }
+        // Skip depth/name/etc until we find an encoding signature or raw data.
+        // Try to locate a PackBits-like run near expected data offset.
+        let data_start = i;
+        let data_end = (i + (w * h * 2) as usize + 1024).min(data.len());
+        let slice = &data[data_start..data_end];
+        let (final_w, final_h) = if w > 1024 || h > 1024 {
+            let scale = 1024.0 / (w.max(h) as f32);
+            ((w as f32 * scale) as u32, (h as f32 * scale) as u32)
+        } else {
+            (w, h)
+        };
+        if let Some(decoded) = try_decode_and_scale(slice, w as usize, h as usize, final_w, final_h) {
+            presets.push(BrushPreset {
+                id: format!("abr_brs2_{}_{}x{}", base_pos + i, final_w, final_h),
+                name: format!("Brush {}x{}", final_w, final_h),
+                category: "Imported (ABR)".to_string(),
+                tip: BrushTip {
+                    style: BrushStyle::Bitmap,
+                    size: final_w.max(final_h) as f32,
+                    opacity: 1.0,
+                    hardness: 1.0,
+                    spacing: 0.1,
+                    jitter_amount: 0.0,
+                    scatter_amount: 0.0,
+                    angle: 0.0,
+                    roundness: 1.0,
+                    spray_particle_size: 2.0,
+                    spray_density: 100,
+                    bitmap_pixels: decoded,
+                    bitmap_w: final_w,
+                    bitmap_h: final_h,
+                    flow: 1.0,
+                    color_variant: false,
+                    variant_amount: 0.0,
+                    density: 1.0,
+                    drawing_angle: false,
+                    rotation_random: 0.0,
+                },
+                style: BrushStyle::Bitmap,
+                pressure_size: true,
+                pressure_opacity: true,
+                pressure_flow: true,
+                jitter_position: 0.0,
+                jitter_angle: 0.0,
+            });
+        }
+        i = data_end;
+    }
+    presets
+}
+
 fn harvest_computed_brushes(data: &[u8]) -> Vec<BrushPreset> {
     let mut presets = Vec::new();
     let marker = b"computedB";
@@ -304,6 +405,227 @@ fn read_u32(cursor: &mut Cursor<&[u8]>) -> u32 {
     u32::from_be_bytes(buf)
 }
 
-pub fn import_krita_preset(_data: &[u8]) -> Option<BrushPreset> {
-    None
+/// Extract brush names from the `desc` block's `Nm  TEXT` tags.
+///
+/// ABR files store a `desc` resource block that contains `BrshVlLs` (Brush
+/// Value Lists). Each entry has a `Nm  TEXT` field with the brush name in
+/// UTF-16 encoding. The names appear in the same order as the brushes in the
+/// `samp` block, so they can be associated by index.
+fn extract_desc_block_names(data: &[u8]) -> Vec<String> {
+    let mut names = Vec::new();
+    let desc_pos = match find_bytes(data, b"8BIMdesc") {
+        Some(p) => p,
+        None => return names,
+    };
+    let size_pos = desc_pos + 8;
+    if size_pos + 4 > data.len() {
+        return names;
+    }
+    let size = u32::from_be_bytes([
+        data[size_pos],
+        data[size_pos + 1],
+        data[size_pos + 2],
+        data[size_pos + 3],
+    ]) as usize;
+    let block_start = size_pos + 4;
+    let block_end = (block_start + size).min(data.len());
+    if block_end <= block_start {
+        return names;
+    }
+    let block = &data[block_start..block_end];
+
+    let mut idx = 0;
+    while idx < block.len() - 8 {
+        if &block[idx..idx + 8] == b"Nm  TEXT" {
+            let p = idx + 8;
+            if p + 4 > block.len() {
+                break;
+            }
+            let nchars = u32::from_be_bytes([block[p], block[p + 1], block[p + 2], block[p + 3]]) as usize;
+            let text_start = p + 4;
+            if nchars == 0 || text_start + nchars * 2 > block.len() {
+                idx += 1;
+                continue;
+            }
+            let chars: Vec<u16> = block[text_start..text_start + nchars * 2]
+                .chunks_exact(2)
+                .map(|b| u16::from_be_bytes([b[0], b[1]]))
+                .collect();
+            let full = String::from_utf16_lossy(&chars);
+            let name = full
+                .split('=')
+                .last()
+                .unwrap_or(&full)
+                .trim_matches('\x00')
+                .to_string();
+            if !name.is_empty() {
+                names.push(name);
+            }
+            idx = text_start + nchars * 2;
+        } else {
+            idx += 1;
+        }
+    }
+    names
+}
+
+/// Apply names extracted from the `desc` block to presets.
+///
+/// The desc block names appear in the same order as sampled brushes were
+/// collected. Computed brushes already have their names from `Nm  TEXT` tags
+/// inside the computed brush data, so only sampled presets (Bitmap style)
+/// get updated.
+fn apply_desc_names(presets: &mut [BrushPreset], desc_names: &[String]) {
+    if desc_names.is_empty() {
+        return;
+    }
+    let mut name_idx = 0;
+    for preset in presets.iter_mut() {
+        if preset.style == BrushStyle::Bitmap && name_idx < desc_names.len() {
+            let new_name = &desc_names[name_idx];
+            if !new_name.is_empty() {
+                preset.name = new_name.clone();
+            }
+            name_idx += 1;
+        }
+    }
+}
+
+/// Parse an ABR file and prefix generated IDs/names so imports from different
+/// files do not collide.
+pub fn import_abr_with_prefix(data: &[u8], prefix: &str) -> Vec<BrushPreset> {
+    let mut presets = import_abr(data);
+    let safe_prefix = prefix.replace(' ', "_").replace('.', "_");
+    for preset in &mut presets {
+        preset.id = format!("{}_{}", safe_prefix, preset.id);
+        preset.name = format!("{} ({})", preset.name, safe_prefix);
+    }
+    presets
+}
+
+/// Parse a Krita brush preset (`.kpp`).
+///
+/// A `.kpp` file is a ZIP archive. This implementation extracts the `preview.png`
+/// thumbnail, converts it to a grayscale alpha mask, and returns a single
+/// `BrushStyle::Bitmap` preset.
+pub fn import_kpp(data: &[u8], name_hint: &str) -> Option<BrushPreset> {
+    use std::io::Cursor;
+    use zip::ZipArchive;
+
+    let cursor = Cursor::new(data);
+    let mut zip = ZipArchive::new(cursor).ok()?;
+    let mut preview_bytes: Option<Vec<u8>> = None;
+    for i in 0..zip.len() {
+        let mut entry = zip.by_index(i).ok()?;
+        let entry_name = entry.name().to_lowercase();
+        if entry_name.ends_with("preview.png") || entry_name == "preview.png" {
+            let mut buf = Vec::new();
+            if entry.read_to_end(&mut buf).is_ok() && !buf.is_empty() {
+                preview_bytes = Some(buf);
+                break;
+            }
+        }
+    }
+    let preview_bytes = preview_bytes?;
+    let img = image::load_from_memory(&preview_bytes).ok()?;
+    let rgba = img.to_rgba8();
+    let (w, h) = rgba.dimensions();
+    if w == 0 || h == 0 {
+        return None;
+    }
+    // Downscale huge previews so GPU brush stamps stay cheap.
+    let (final_w, final_h) = if w > 512 || h > 512 {
+        let scale = 512.0 / (w.max(h) as f32);
+        ((w as f32 * scale) as u32, (h as f32 * scale) as u32)
+    } else {
+        (w, h)
+    };
+    let mut gray = Vec::with_capacity((final_w * final_h) as usize);
+    for y in 0..final_h {
+        for x in 0..final_w {
+            let src_x = (x as f32 * (w as f32 / final_w as f32)) as u32;
+            let src_y = (y as f32 * (h as f32 / final_h as f32)) as u32;
+            let px = rgba.get_pixel(src_x.min(w - 1), src_y.min(h - 1));
+            // Use perceived luminance from RGB and keep full alpha range.
+            let l = (0.299 * px[0] as f32 + 0.587 * px[1] as f32 + 0.114 * px[2] as f32)
+                .clamp(0.0, 255.0) as u8;
+            let a = px[3];
+            // Mask value = luminance scaled by alpha.
+            gray.push((l as u16 * a as u16 / 255) as u8);
+        }
+    }
+    Some(BrushPreset {
+        id: format!("kpp_imported_{}_{}x{}", name_hint.replace(' ', "_"), final_w, final_h),
+        name: format!("{} (KPP)", name_hint),
+        category: "Imported".to_string(),
+        tip: BrushTip {
+            style: BrushStyle::Bitmap,
+            size: final_w.max(final_h) as f32,
+            opacity: 1.0,
+            hardness: 1.0,
+            spacing: 0.1,
+            jitter_amount: 0.0,
+            scatter_amount: 0.0,
+            angle: 0.0,
+            roundness: 1.0,
+            spray_particle_size: 2.0,
+            spray_density: 100,
+            bitmap_pixels: gray,
+            bitmap_w: final_w,
+            bitmap_h: final_h,
+            flow: 1.0,
+            color_variant: false,
+            variant_amount: 0.0,
+            density: 1.0,
+            drawing_angle: false,
+            rotation_random: 0.0,
+        },
+        style: BrushStyle::Bitmap,
+        pressure_size: true,
+        pressure_opacity: true,
+        pressure_flow: true,
+        jitter_position: 0.0,
+        jitter_angle: 0.0,
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_extract_desc_block_names() {
+        let path = "/mnt/data/Downloads/Square Brushes.abr";
+        let data = match std::fs::read(path) {
+            Ok(d) => d,
+            Err(_) => {
+                eprintln!("Skipping test: {} not found", path);
+                return;
+            }
+        };
+        let names = extract_desc_block_names(&data);
+        assert!(!names.is_empty(), "Should extract names from desc block");
+        assert!(
+            names[0].contains("Hard Square"),
+            "First name should be descriptive, got: {}",
+            names[0]
+        );
+    }
+
+    #[test]
+    fn test_abr_import_with_names() {
+        let path = "/mnt/data/Downloads/Square Brushes.abr";
+        let data = match std::fs::read(path) {
+            Ok(d) => d,
+            Err(_) => {
+                eprintln!("Skipping test: {} not found", path);
+                return;
+            }
+        };
+        let presets = import_abr(&data);
+        let bitmap: Vec<_> = presets.iter().filter(|p| p.style == BrushStyle::Bitmap).collect();
+        assert!(!bitmap.is_empty(), "Should have bitmap presets");
+        let has_names = bitmap.iter().any(|p| !p.name.starts_with("Brush "));
+        assert!(has_names, "Bitmap presets should have descriptive names");
+    }
 }

hcie-egui-app/crates/hcie-gui-egui/src/canvas/mod.rs

@@ -4,6 +4,7 @@ use crate::app::{tools::shape_sync, AppDocument, SelectionTransform, ToolState,
 use crate::event_bus::{AppEvent, EventBus};
 use eframe::egui;
 use hcie_engine_api::{LayerData, Tool, VectorEditHandle, VectorShape, ZOOM_MAX, ZOOM_MIN};
+use hcie_engine_api::brush::BrushStyle;
 
 pub mod render;
 pub mod text_overlay;
@@ -1433,18 +1434,84 @@ impl<'a> egui::Widget for CanvasWidget<'a> {
             if self.state.active_tool.shows_pen_tips() {
                 let screen_x = canvas_rect.min.x + cx as f32 * zoom;
                 let screen_y = canvas_rect.min.y + cy as f32 * zoom;
-                let radius = self.state.active_size() * zoom * 0.5;
                 let color = egui::Color32::from_rgba_unmultiplied(
                     self.state.primary_color[0],
                     self.state.primary_color[1],
                     self.state.primary_color[2],
                     180,
                 );
-                painter.circle_stroke(
-                    egui::pos2(screen_x, screen_y),
-                    radius,
-                    egui::Stroke::new(1.5, color),
-                );
+                let active_tip = self
+                    .state
+                    .brush_presets
+                    .iter()
+                    .find(|p| p.id == self.state.active_brush_preset_id)
+                    .map(|p| &p.tip);
+                if let Some(tip) = active_tip {
+                    if tip.style == BrushStyle::Bitmap
+                        && !tip.bitmap_pixels.is_empty()
+                        && tip.bitmap_w > 0
+                        && tip.bitmap_h > 0
+                    {
+                        let bw = tip.bitmap_w as f32;
+                        let bh = tip.bitmap_h as f32;
+                        let stamp_size = self.state.active_size() * zoom;
+                        let scale = (stamp_size / bw).min(stamp_size / bh);
+                        let draw_w = bw * scale;
+                        let draw_h = bh * scale;
+                        let origin_x = screen_x - draw_w * 0.5;
+                        let origin_y = screen_y - draw_h * 0.5;
+                        let px_size = scale.max(1.0);
+                        let mut shapes = Vec::new();
+                        let mut py = 0.0;
+                        let mut sy = 0u32;
+                        while sy < tip.bitmap_h {
+                            let mut px = 0.0;
+                            let mut sx = 0u32;
+                            while sx < tip.bitmap_w {
+                                let mask =
+                                    tip.bitmap_pixels[(sy * tip.bitmap_w + sx) as usize] as f32
+                                        / 255.0;
+                                if mask > 0.01 {
+                                    let a = (mask * 180.0).round() as u8;
+                                    let c = egui::Color32::from_rgba_unmultiplied(
+                                        color.r(),
+                                        color.g(),
+                                        color.b(),
+                                        a,
+                                    );
+                                    let p = egui::pos2(origin_x + px, origin_y + py);
+                                    shapes.push(egui::Shape::rect_filled(
+                                        egui::Rect::from_min_size(
+                                            p,
+                                            egui::vec2(px_size, px_size),
+                                        ),
+                                        0.0,
+                                        c,
+                                    ));
+                                }
+                                px += px_size;
+                                sx += 1;
+                            }
+                            py += px_size;
+                            sy += 1;
+                        }
+                        painter.add(egui::Shape::Vec(shapes));
+                    } else {
+                        let radius = self.state.active_size() * zoom * 0.5;
+                        painter.circle_stroke(
+                            egui::pos2(screen_x, screen_y),
+                            radius,
+                            egui::Stroke::new(1.5, color),
+                        );
+                    }
+                } else {
+                    let radius = self.state.active_size() * zoom * 0.5;
+                    painter.circle_stroke(
+                        egui::pos2(screen_x, screen_y),
+                        radius,
+                        egui::Stroke::new(1.5, color),
+                    );
+                }
             }
         }