Simplify: extract paint_glyph, drop unused param and redundant comments

- Add paint_glyph(painter, rect, glyph) to render.rs; draw_glyph now
  delegates to it, eliminating the duplicated rect_filled+text pattern
  that appeared in four places across editor.rs and glyph_picker.rs
- Remove unused _board param from show_editor_panel and its call site
- Drop redundant section-header comments in glyph_picker.rs (the
  ui.label() calls immediately below already name each section)
- Remove extracted fg/bg/cur_ch locals in the char grid loop now that
  paint_glyph accepts a Glyph directly
- Fix CLAUDE.md update phase description (stale from pre-refactor)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

CLAUDE.md

@@ -38,8 +38,9 @@ The game is a single Rust binary using **eframe 0.33 / egui 0.33** for the GUI.
 `update` is structured in phases:
 - Input handling — arrow keys move the player (Play mode only)
 - `egui::TopBottomPanel::top` — menu bar (File → Exit, Play/Edit mode toggle)
-- `egui::SidePanel::right` — archetype palette panel (Edit mode only; declared before CentralPanel)
+- `editor::show_editor_panel` — archetype palette panel (Edit mode only; declared before CentralPanel)
-- `egui::CentralPanel::default` — game viewport; rendered with `ui.painter()`; click-to-paint in Edit mode
+- `egui::CentralPanel::default` — game viewport; rendered with `render::draw_board`; click-to-paint in Edit mode
+- `glyph_picker::show` — floating picker dialog (Edit mode only, when open)
 
 ### Modules
 

src/editor.rs

@@ -1,8 +1,8 @@
 use eframe::egui;
-use egui::{Align2, FontId, Sense, vec2};
+use egui::{Sense, vec2};
 
-use crate::game::{Archetype, Board, Glyph, ALL_ARCHETYPES};
+use crate::game::{Archetype, Glyph, ALL_ARCHETYPES};
-use crate::render::{CELL_H, CELL_W, PALETTE_PANEL_W};
+use crate::render::{CELL_H, CELL_W, PALETTE_PANEL_W, paint_glyph};
 
 /// Which tab is active in the editor side panel.
 #[derive(Copy, Clone, PartialEq, Eq)]
@@ -43,12 +43,11 @@ impl EditorState {
 ///
 /// Shows tab bar (Palette / Board / World) and, on the Palette tab, the
 /// scrollable archetype list and current-glyph preview button.
-pub(crate) fn show_editor_panel(ctx: &egui::Context, editor: &mut EditorState, _board: &Board) {
+pub(crate) fn show_editor_panel(ctx: &egui::Context, editor: &mut EditorState) {
     egui::SidePanel::right("palette_panel")
         .resizable(true)
         .default_width(PALETTE_PANEL_W)
         .show(ctx, |ui| {
-            // Tab bar
             ui.horizontal(|ui| {
                 ui.selectable_value(&mut editor.tab, EditorTab::Palette, "Palette");
                 ui.selectable_value(&mut editor.tab, EditorTab::Board,   "Board");
@@ -72,12 +71,7 @@ pub(crate) fn show_editor_panel(ctx: &egui::Context, editor: &mut EditorState, _
                                 ui.horizontal(|ui| {
                                     let (r, cell_resp) = ui.allocate_exact_size(
                                         vec2(CELL_W, CELL_H), Sense::click());
-                                    {
+                                    paint_glyph(ui.painter(), r, &glyph);
-                                        let p = ui.painter();
-                                        p.rect_filled(r, 0.0, glyph.bg);
-                                        p.text(r.center(), Align2::CENTER_CENTER,
-                                            glyph.ch, FontId::monospace(CELL_H), glyph.fg);
-                                    }
                                     let label_resp =
                                         ui.selectable_label(is_selected, archetype.name());
                                     if cell_resp.clicked() || label_resp.clicked() {
@@ -94,17 +88,7 @@ pub(crate) fn show_editor_panel(ctx: &egui::Context, editor: &mut EditorState, _
                     // Paint a preview cell showing the current glyph, sized like a board cell.
                     let (cell_rect, glyph_btn) =
                         ui.allocate_exact_size(vec2(CELL_W, CELL_H), Sense::click());
-                    {
+                    paint_glyph(ui.painter(), cell_rect, &editor.glyph);
-                        let p = ui.painter();
-                        p.rect_filled(cell_rect, 0.0, editor.glyph.bg);
-                        p.text(
-                            cell_rect.center(),
-                            Align2::CENTER_CENTER,
-                            editor.glyph.ch,
-                            FontId::monospace(CELL_H),
-                            editor.glyph.fg,
-                        );
-                    }
                     if glyph_btn.clicked() {
                         editor.glyph_picker_open = true;
                     }

src/glyph_picker.rs

@@ -1,8 +1,8 @@
 use eframe::egui;
-use egui::{Align2, Color32, FontId, Rect, Sense, Stroke, vec2};
+use egui::{Color32, Rect, Sense, Stroke, vec2};
 
 use crate::game::{Archetype, Glyph};
-use crate::render::{CELL_H, CELL_W, pos_to_cell};
+use crate::render::{CELL_H, CELL_W, paint_glyph, pos_to_cell};
 
 /// Renders the floating glyph-picker dialog and updates `glyph` in place.
 ///
@@ -32,22 +32,17 @@ pub(crate) fn show(
         .resizable(false)
         .open(open)
         .show(ctx, |ui| {
-            // ----- Board palette -----
             ui.label("Board palette");
             ui.horizontal_wrapped(|ui| {
                 for &g in &board_glyphs {
                     let (r, resp) =
                         ui.allocate_exact_size(vec2(CELL_W, CELL_H), Sense::click());
-                    {
                     let p = ui.painter();
-                        p.rect_filled(r, 0.0, g.bg);
+                    paint_glyph(p, r, &g);
-                        p.text(r.center(), Align2::CENTER_CENTER, g.ch,
-                            FontId::monospace(CELL_H), g.fg);
                     if g == *glyph {
                         p.rect_stroke(r, 0.0, Stroke::new(1.0, Color32::WHITE),
                             egui::epaint::StrokeKind::Middle);
                     }
-                    }
                     if resp.clicked() {
                         *glyph = g;
                     }
@@ -56,7 +51,6 @@ pub(crate) fn show(
 
             ui.separator();
 
-            // ----- Colors -----
             ui.label("Colors");
             ui.horizontal(|ui| {
                 ui.label("FG");
@@ -69,7 +63,6 @@ pub(crate) fn show(
 
             ui.separator();
 
-            // ----- Character grid -----
             // 16 columns × 6 rows covering printable ASCII 0x20–0x7E.
             ui.label("Character");
             const CHAR_COLS: usize = 16;
@@ -79,9 +72,6 @@ pub(crate) fn show(
             let grid_size = vec2(CHAR_COLS as f32 * CELL_W, rows as f32 * CELL_H);
             let (grid_rect, grid_resp) =
                 ui.allocate_exact_size(grid_size, Sense::click());
-            let fg = glyph.fg;
-            let bg = glyph.bg;
-            let cur_ch = glyph.ch;
             {
                 let p = ui.painter();
                 for (i, &ch) in chars.iter().enumerate() {
@@ -90,10 +80,8 @@ pub(crate) fn show(
                     let tl = grid_rect.min
                         + vec2(col as f32 * CELL_W, row as f32 * CELL_H);
                     let cell = Rect::from_min_size(tl, vec2(CELL_W, CELL_H));
-                    p.rect_filled(cell, 0.0, bg);
+                    paint_glyph(p, cell, &Glyph { ch, fg: glyph.fg, bg: glyph.bg });
-                    p.text(cell.center(), Align2::CENTER_CENTER, ch,
+                    if ch == glyph.ch {
-                        FontId::monospace(CELL_H), fg);
-                    if ch == cur_ch {
                         p.rect_stroke(cell, 0.0, Stroke::new(1.0, Color32::WHITE),
                             egui::epaint::StrokeKind::Middle);
                     }

src/main.rs

@@ -95,7 +95,7 @@ impl eframe::App for App {
         // --- Editor side panel ---
         // Must be declared before CentralPanel so egui allocates its space first.
         if self.mode == AppMode::Edit {
-            show_editor_panel(ctx, &mut self.editor, &self.state.board);
+            show_editor_panel(ctx, &mut self.editor);
         }
 
         // --- Board rendering ---

src/render.rs

@@ -49,11 +49,17 @@ pub(crate) const MIN_WINDOW_W: f32 = CELL_W * 10.0 + 2.0 * PANEL_MARGIN;
 /// Minimum window height: enough room for 5 cells plus menu and margins.
 pub(crate) const MIN_WINDOW_H: f32 = CELL_H * 5.0 + MENU_H + 2.0 * PANEL_MARGIN;
 
-/// Draws a single cell at grid position `(x, y)` using the given glyph.
+/// Paints a glyph into an already-allocated `rect`.
 ///
-/// Each cell is rendered as two layers:
+/// Unlike [`draw_glyph`], this does not compute the rect from grid coordinates —
-/// 1. A filled rectangle in `glyph.bg` covering the full cell area.
+/// the caller owns the rect (typically from [`egui::Ui::allocate_exact_size`])
-/// 2. A monospace character (`glyph.ch`) in `glyph.fg`, centered in the cell.
+/// and handles interaction. Use this when you need the click [`egui::Response`].
+pub(crate) fn paint_glyph(painter: &egui::Painter, rect: Rect, glyph: &Glyph) {
+    painter.rect_filled(rect, 0.0, glyph.bg);
+    painter.text(rect.center(), Align2::CENTER_CENTER, glyph.ch, FontId::monospace(CELL_H), glyph.fg);
+}
+
+/// Draws a single cell at grid position `(x, y)` using the given glyph.
 ///
 /// `origin` is the pixel position of cell `(0, 0)` — the top-left corner of
 /// the board within the panel. Cell positions are computed from `origin` using
@@ -61,9 +67,7 @@ pub(crate) const MIN_WINDOW_H: f32 = CELL_H * 5.0 + MENU_H + 2.0 * PANEL_MARGIN;
 pub(crate) fn draw_glyph(painter: &egui::Painter, origin: Pos2, x: usize, y: usize, glyph: &Glyph) {
     let tl = origin + vec2(x as f32 * CELL_W, y as f32 * CELL_H);
     let rect = Rect::from_min_size(tl, vec2(CELL_W, CELL_H));
-    let center = rect.center();
+    paint_glyph(painter, rect, glyph);
-    painter.rect_filled(rect, 0.0, glyph.bg);
-    painter.text(center, Align2::CENTER_CENTER, glyph.ch, FontId::monospace(CELL_H), glyph.fg);
 }
 
 /// Draws all board cells then the player overlay at `origin`.