fix(app): render terminal art at exact cell geometry

Native font glyph bounds do not reliably fill terminal cells, and long box-drawing runs accumulate advance drift. Paint block and box glyphs from cell geometry while preserving the original Unicode cell model for selection and copying.

packages/app/src/terminal/native-renderer/colors.ts

@@ -39,6 +39,7 @@ const FLAG_STRIKETHROUGH = 1 << 5;
 interface ResolvedCellStyle {
   key: string;
   style: TextStyle;
+  foregroundColor: string;
 }
 
 interface ResolvedCellColors {
@@ -227,7 +228,7 @@ export function createTerminalCellStyleResolver(theme: ITheme): TerminalCellStyl
       });
       const cachedStyle = styleCache.get(key);
       if (cachedStyle) {
-        return { key, style: cachedStyle };
+        return { key, style: cachedStyle, foregroundColor: colors.foreground };
       }
 
       const style = createTextStyle({
@@ -237,7 +238,7 @@ export function createTerminalCellStyleResolver(theme: ITheme): TerminalCellStyl
         flags,
       });
       styleCache.set(key, style);
-      return { key, style };
+      return { key, style, foregroundColor: colors.foreground };
     },
   };
 }

packages/app/src/terminal/native-renderer/terminal-custom-glyph.test.ts

@@ -0,0 +1,88 @@
+import { describe, expect, it } from "vitest";
+
+import { resolveTerminalCustomGlyph } from "./terminal-custom-glyph";
+
+describe("native terminal custom glyphs", () => {
+  it("fills the complete cell for the full block used by the Claude mascot", () => {
+    expect(resolveTerminalCustomGlyph("█")).toEqual({
+      kind: "rects",
+      rects: [{ x: 0, y: 0, width: 1, height: 1 }],
+    });
+  });
+
+  it("draws every Claude mascot block from exact cell fractions", () => {
+    const mascot = ["▐▛███▜▌", "▝▜█████▛▘", "▘▘ ▝▝"];
+    const customGlyphs = mascot
+      .join("")
+      .replaceAll(" ", "")
+      .split("")
+      .map(resolveTerminalCustomGlyph);
+
+    expect(customGlyphs).not.toContain(null);
+    expect(resolveTerminalCustomGlyph("▐")).toEqual({
+      kind: "rects",
+      rects: [{ x: 0.5, y: 0, width: 0.5, height: 1 }],
+    });
+    expect(resolveTerminalCustomGlyph("▛")).toEqual({
+      kind: "rects",
+      rects: [
+        { x: 0, y: 0, width: 0.5, height: 0.5 },
+        { x: 0.5, y: 0, width: 0.5, height: 0.5 },
+        { x: 0, y: 0.5, width: 0.5, height: 0.5 },
+      ],
+    });
+    expect(resolveTerminalCustomGlyph("▝")).toEqual({
+      kind: "rects",
+      rects: [{ x: 0.5, y: 0, width: 0.5, height: 0.5 }],
+    });
+  });
+
+  it("connects the rounded Claude welcome frame to every cell edge", () => {
+    expect(resolveTerminalCustomGlyph("─")).toEqual({
+      kind: "path",
+      path: "M0,.5 L1,.5",
+      strokeWidth: 1,
+    });
+    expect(resolveTerminalCustomGlyph("│")).toEqual({
+      kind: "path",
+      path: "M.5,0 L.5,1",
+      strokeWidth: 1,
+    });
+    expect(resolveTerminalCustomGlyph("╭")).toEqual({
+      kind: "path",
+      path: "M.5,1 L.5,.75 Q.5,.5 .75,.5 L1,.5",
+      strokeWidth: 1,
+    });
+    expect(resolveTerminalCustomGlyph("╮")).toEqual({
+      kind: "path",
+      path: "M0,.5 L.25,.5 Q.5,.5 .5,.75 L.5,1",
+      strokeWidth: 1,
+    });
+    expect(resolveTerminalCustomGlyph("╰")).toEqual({
+      kind: "path",
+      path: "M.5,0 L.5,.25 Q.5,.5 .75,.5 L1,.5",
+      strokeWidth: 1,
+    });
+    expect(resolveTerminalCustomGlyph("╯")).toEqual({
+      kind: "path",
+      path: "M0,.5 L.25,.5 Q.5,.5 .5,.25 L.5,0",
+      strokeWidth: 1,
+    });
+  });
+
+  it("keeps ordinary terminal text on the font renderer", () => {
+    expect(resolveTerminalCustomGlyph("C")).toBeNull();
+    expect(resolveTerminalCustomGlyph(" ")).toBeNull();
+  });
+
+  it("covers common light and heavy terminal ASCII-art frames", () => {
+    const frames = [
+      "┌────┬────┐│    │    │├────┼────┤└────┴────┘",
+      "┏━━━━┳━━━━┓┃    ┃    ┃┣━━━━╋━━━━┫┗━━━━┻━━━━┛",
+    ];
+
+    for (const char of frames.join("").replaceAll(" ", "")) {
+      expect(resolveTerminalCustomGlyph(char), `missing custom glyph ${char}`).not.toBeNull();
+    }
+  });
+});

packages/app/src/terminal/native-renderer/terminal-custom-glyph.ts

@@ -0,0 +1,119 @@
+export interface TerminalGlyphRect {
+  x: number;
+  y: number;
+  width: number;
+  height: number;
+}
+
+export interface TerminalRectGlyph {
+  kind: "rects";
+  rects: readonly TerminalGlyphRect[];
+}
+
+export interface TerminalPathGlyph {
+  kind: "path";
+  path: string;
+  strokeWidth: number;
+}
+
+export type TerminalCustomGlyph = TerminalRectGlyph | TerminalPathGlyph;
+
+const LIGHT_BOX_GLYPHS: Readonly<Record<string, TerminalPathGlyph>> = {
+  "─": path("M0,.5 L1,.5"),
+  "│": path("M.5,0 L.5,1"),
+  "┌": path("M.5,1 L.5,.5 L1,.5"),
+  "┐": path("M0,.5 L.5,.5 L.5,1"),
+  "└": path("M.5,0 L.5,.5 L1,.5"),
+  "┘": path("M0,.5 L.5,.5 L.5,0"),
+  "├": path("M.5,0 L.5,1 M.5,.5 L1,.5"),
+  "┤": path("M.5,0 L.5,1 M.5,.5 L0,.5"),
+  "┬": path("M0,.5 L1,.5 M.5,.5 L.5,1"),
+  "┴": path("M0,.5 L1,.5 M.5,.5 L.5,0"),
+  "┼": path("M0,.5 L1,.5 M.5,0 L.5,1"),
+  "╭": path("M.5,1 L.5,.75 Q.5,.5 .75,.5 L1,.5"),
+  "╮": path("M0,.5 L.25,.5 Q.5,.5 .5,.75 L.5,1"),
+  "╰": path("M.5,0 L.5,.25 Q.5,.5 .75,.5 L1,.5"),
+  "╯": path("M0,.5 L.25,.5 Q.5,.5 .5,.25 L.5,0"),
+};
+
+const HEAVY_BOX_GLYPHS: Readonly<Record<string, TerminalPathGlyph>> = {
+  "━": path("M0,.5 L1,.5", 3),
+  "┃": path("M.5,0 L.5,1", 3),
+  "┏": path("M.5,1 L.5,.5 L1,.5", 3),
+  "┓": path("M0,.5 L.5,.5 L.5,1", 3),
+  "┗": path("M.5,0 L.5,.5 L1,.5", 3),
+  "┛": path("M0,.5 L.5,.5 L.5,0", 3),
+  "┣": path("M.5,0 L.5,1 M.5,.5 L1,.5", 3),
+  "┫": path("M.5,0 L.5,1 M.5,.5 L0,.5", 3),
+  "┳": path("M0,.5 L1,.5 M.5,.5 L.5,1", 3),
+  "┻": path("M0,.5 L1,.5 M.5,.5 L.5,0", 3),
+  "╋": path("M0,.5 L1,.5 M.5,0 L.5,1", 3),
+};
+
+const BLOCK_GLYPHS: Readonly<Record<string, TerminalRectGlyph>> = {
+  "▀": rects(rect(0, 0, 1, 0.5)),
+  "▁": rects(rect(0, 0.875, 1, 0.125)),
+  "▂": rects(rect(0, 0.75, 1, 0.25)),
+  "▃": rects(rect(0, 0.625, 1, 0.375)),
+  "▄": rects(rect(0, 0.5, 1, 0.5)),
+  "▅": rects(rect(0, 0.375, 1, 0.625)),
+  "▆": rects(rect(0, 0.25, 1, 0.75)),
+  "▇": rects(rect(0, 0.125, 1, 0.875)),
+  "█": rects(rect(0, 0, 1, 1)),
+  "▉": rects(rect(0, 0, 0.875, 1)),
+  "▊": rects(rect(0, 0, 0.75, 1)),
+  "▋": rects(rect(0, 0, 0.625, 1)),
+  "▌": rects(rect(0, 0, 0.5, 1)),
+  "▍": rects(rect(0, 0, 0.375, 1)),
+  "▎": rects(rect(0, 0, 0.25, 1)),
+  "▏": rects(rect(0, 0, 0.125, 1)),
+  "▐": rects(rect(0.5, 0, 0.5, 1)),
+  "▔": rects(rect(0, 0, 1, 0.125)),
+  "▕": rects(rect(0.875, 0, 0.125, 1)),
+  "▖": rects(lowerLeft()),
+  "▗": rects(lowerRight()),
+  "▘": rects(upperLeft()),
+  "▙": rects(upperLeft(), lowerLeft(), lowerRight()),
+  "▚": rects(upperLeft(), lowerRight()),
+  "▛": rects(upperLeft(), upperRight(), lowerLeft()),
+  "▜": rects(upperLeft(), upperRight(), lowerRight()),
+  "▝": rects(upperRight()),
+  "▞": rects(upperRight(), lowerLeft()),
+  "▟": rects(upperRight(), lowerLeft(), lowerRight()),
+};
+
+export function resolveTerminalCustomGlyph(char: string): TerminalCustomGlyph | null {
+  return LIGHT_BOX_GLYPHS[char] ?? HEAVY_BOX_GLYPHS[char] ?? BLOCK_GLYPHS[char] ?? null;
+}
+
+export function isTerminalCustomGlyph(char: string): boolean {
+  return resolveTerminalCustomGlyph(char) !== null;
+}
+
+function path(pathData: string, strokeWidth = 1): TerminalPathGlyph {
+  return { kind: "path", path: pathData, strokeWidth };
+}
+
+function rect(x: number, y: number, width: number, height: number): TerminalGlyphRect {
+  return { x, y, width, height };
+}
+
+function rects(...values: TerminalGlyphRect[]): TerminalRectGlyph {
+  return { kind: "rects", rects: values };
+}
+
+function upperLeft(): TerminalGlyphRect {
+  return rect(0, 0, 0.5, 0.5);
+}
+
+function upperRight(): TerminalGlyphRect {
+  return rect(0.5, 0, 0.5, 0.5);
+}
+
+function lowerLeft(): TerminalGlyphRect {
+  return rect(0, 0.5, 0.5, 0.5);
+}
+
+function lowerRight(): TerminalGlyphRect {
+  return rect(0.5, 0.5, 0.5, 0.5);
+}

packages/app/src/terminal/native-renderer/terminal-grid-view.native.tsx

@@ -9,6 +9,7 @@ import {
   type ViewStyle,
 } from "react-native";
 import { StyleSheet } from "react-native-unistyles";
+import Svg, { G, Path } from "react-native-svg";
 import type { ITheme } from "@xterm/xterm";
 
 import {
@@ -16,6 +17,7 @@ import {
   DEFAULT_TERMINAL_THEME,
   NATIVE_TERMINAL_SELECTION_COLORS,
 } from "./colors";
+import type { TerminalGlyphRect } from "./terminal-custom-glyph";
 import { resolveNativeTerminalFontFamily } from "./font.native";
 import type { TerminalViewportState } from "./headless-terminal-state";
 import {
@@ -24,7 +26,13 @@ import {
   resolveTerminalCursorOffset,
   type TerminalGridCellMetrics,
 } from "./terminal-grid-metrics";
-import { buildRows, type TerminalRowModel, type TerminalRun } from "./terminal-row-model";
+import {
+  buildRows,
+  type TerminalCustomGlyphCell,
+  type TerminalCustomGlyphRun,
+  type TerminalRowModel,
+  type TerminalRun,
+} from "./terminal-row-model";
 import type { TerminalSelectionRange } from "./terminal-selection";
 
 const MEASURE_TEXT = "mmmmmmmmmm";
@@ -109,9 +117,100 @@ function TerminalGridRun({ run, cellWidth, cellHeight, textStyle }: TerminalGrid
 
   return (
     <View style={runStyle}>
-      <Text numberOfLines={1} style={runTextStyle}>
+      {run.renderKind === "custom-glyph" ? (
-        {run.text}
+        <TerminalGridCustomGlyphRun run={run} cellWidth={cellWidth} cellHeight={cellHeight} />
-      </Text>
+      ) : (
+        <Text numberOfLines={1} style={runTextStyle}>
+          {run.text}
+        </Text>
+      )}
+    </View>
+  );
+}
+
+interface TerminalGridCustomGlyphRunProps {
+  run: TerminalCustomGlyphRun;
+  cellWidth: number;
+  cellHeight: number;
+}
+
+interface TerminalGridCustomGlyphRectProps {
+  cell: TerminalCustomGlyphCell;
+  rect: TerminalGlyphRect;
+  cellWidth: number;
+  cellHeight: number;
+  foregroundColor: string;
+}
+
+function TerminalGridCustomGlyphRect({
+  cell,
+  rect,
+  cellWidth,
+  cellHeight,
+  foregroundColor,
+}: TerminalGridCustomGlyphRectProps) {
+  const style = useMemo<ViewStyle>(
+    () => ({
+      position: "absolute",
+      backgroundColor: foregroundColor,
+      left: (cell.offset + rect.x) * cellWidth,
+      top: rect.y * cellHeight,
+      width: rect.width * cellWidth,
+      height: rect.height * cellHeight,
+    }),
+    [cell.offset, cellHeight, cellWidth, foregroundColor, rect],
+  );
+
+  return <View style={style} />;
+}
+
+function TerminalGridCustomGlyphRun({
+  run,
+  cellWidth,
+  cellHeight,
+}: TerminalGridCustomGlyphRunProps) {
+  const opacity = typeof run.style.opacity === "number" ? run.style.opacity : 1;
+
+  return (
+    <View style={[styles.customGlyphRun, { opacity }]}>
+      {run.glyphs.map((cell) =>
+        cell.glyph.kind === "rects"
+          ? cell.glyph.rects.map((rect) => (
+              <TerminalGridCustomGlyphRect
+                key={`${cell.key}:${rect.x}:${rect.y}:${rect.width}:${rect.height}`}
+                cell={cell}
+                rect={rect}
+                cellWidth={cellWidth}
+                cellHeight={cellHeight}
+                foregroundColor={run.foregroundColor}
+              />
+            ))
+          : null,
+      )}
+      <Svg
+        height={cellHeight}
+        pointerEvents="none"
+        preserveAspectRatio="none"
+        style={styles.customGlyphSvg}
+        viewBox={`0 0 ${run.cellCount} 1`}
+        width={run.cellCount * cellWidth}
+      >
+        <G fill="none" stroke={run.foregroundColor}>
+          {run.glyphs.map((cell) =>
+            cell.glyph.kind === "path" ? (
+              <Path
+                d={cell.glyph.path}
+                key={cell.key}
+                strokeLinecap="butt"
+                strokeLinejoin="miter"
+                strokeWidth={cell.glyph.strokeWidth}
+                transform={`translate(${cell.offset} 0)`}
+                vectorEffect="non-scaling-stroke"
+              />
+            ) : null,
+          )}
+        </G>
+      </Svg>
     </View>
   );
 }
@@ -337,6 +436,15 @@ const styles = StyleSheet.create({
   run: {
     overflow: "hidden",
   },
+  customGlyphRun: {
+    flex: 1,
+    position: "relative",
+  },
+  customGlyphSvg: {
+    left: 0,
+    position: "absolute",
+    top: 0,
+  },
   rowText: {
     includeFontPadding: false,
     margin: 0,

packages/app/src/terminal/native-renderer/terminal-row-model.test.ts

@@ -79,4 +79,42 @@ describe("terminal row model", () => {
     ]);
     expect(rows[0].hash).not.toBe(buildRows({ grid, resolver })[0].hash);
   });
+
+  test("splits Claude box drawing from font text at exact terminal columns", () => {
+    const resolver = createTerminalCellStyleResolver(DEFAULT_TERMINAL_THEME);
+    const frame = "╭─ Claude Code ───╮";
+
+    const [row] = buildRows({
+      grid: [frame.split("").map((char) => cell(char, { fg: 1, fgMode: 1 }))],
+      resolver,
+    });
+
+    expect(
+      row.runs.map((run) => ({
+        text: run.text,
+        cellCount: run.cellCount,
+        renderKind: run.renderKind,
+      })),
+    ).toEqual([
+      { text: "╭─", cellCount: 2, renderKind: "custom-glyph" },
+      { text: " Claude Code ", cellCount: 13, renderKind: "text" },
+      { text: "───╮", cellCount: 4, renderKind: "custom-glyph" },
+    ]);
+  });
+
+  test("keeps Claude mascot glyphs custom while preserving copied row text", () => {
+    const resolver = createTerminalCellStyleResolver(DEFAULT_TERMINAL_THEME);
+    const mascot = "▐▛███▜▌   Claude Code";
+
+    const [row] = buildRows({
+      grid: [mascot.split("").map((char) => cell(char, { fg: 1, fgMode: 1 }))],
+      resolver,
+    });
+
+    expect(row.runs.map((run) => [run.text, run.renderKind])).toEqual([
+      ["▐▛███▜▌", "custom-glyph"],
+      ["   Claude Code", "text"],
+    ]);
+    expect(row.runs.map((run) => run.text).join("")).toBe(mascot);
+  });
 });

packages/app/src/terminal/native-renderer/terminal-row-model.ts

@@ -2,6 +2,7 @@ import type { TextStyle } from "react-native";
 import type { TerminalCell } from "@getpaseo/protocol/messages";
 
 import type { TerminalCellStyleResolver } from "./colors";
+import { resolveTerminalCustomGlyph, type TerminalCustomGlyph } from "./terminal-custom-glyph";
 import type { TerminalSelectionRange } from "./terminal-selection";
 
 const WIDE_CHAR_RANGES: ReadonlyArray<readonly [number, number]> = [
@@ -17,12 +18,30 @@ const WIDE_CHAR_RANGES: ReadonlyArray<readonly [number, number]> = [
   [0x1f300, 0x1faff],
 ];
 
-export interface TerminalRun {
+interface TerminalRunBase {
   key: string;
   text: string;
   cellCount: number;
   styleKey: string;
   style: TextStyle;
+  foregroundColor: string;
+}
+
+export interface TerminalTextRun extends TerminalRunBase {
+  renderKind: "text";
+}
+
+export interface TerminalCustomGlyphRun extends TerminalRunBase {
+  renderKind: "custom-glyph";
+  glyphs: TerminalCustomGlyphCell[];
+}
+
+export type TerminalRun = TerminalCustomGlyphRun | TerminalTextRun;
+
+export interface TerminalCustomGlyphCell {
+  key: string;
+  offset: number;
+  glyph: TerminalCustomGlyph;
 }
 
 export interface TerminalRowModel {
@@ -83,22 +102,47 @@ function appendRun(input: {
   cellCount: number;
   styleKey: string;
   style: TextStyle;
+  foregroundColor: string;
+  customGlyph: TerminalCustomGlyph | null;
   col: number;
 }): void {
+  const renderKind = input.customGlyph ? "custom-glyph" : "text";
   const previousRun = input.runs[input.runs.length - 1];
-  if (previousRun && previousRun.styleKey === input.styleKey) {
+  if (
+    previousRun &&
+    previousRun.styleKey === input.styleKey &&
+    previousRun.renderKind === renderKind
+  ) {
+    const offset = previousRun.cellCount;
     previousRun.text += input.text;
     previousRun.cellCount += input.cellCount;
+    if (previousRun.renderKind === "custom-glyph" && input.customGlyph) {
+      previousRun.glyphs.push({
+        key: `${input.col}:${input.text}`,
+        offset,
+        glyph: input.customGlyph,
+      });
+    }
     return;
   }
 
-  input.runs.push({
+  const baseRun: TerminalRunBase = {
     key: `${input.col}:${input.styleKey}`,
     text: input.text,
     cellCount: input.cellCount,
     styleKey: input.styleKey,
     style: input.style,
-  });
+    foregroundColor: input.foregroundColor,
+  };
+  if (input.customGlyph) {
+    input.runs.push({
+      ...baseRun,
+      renderKind: "custom-glyph",
+      glyphs: [{ key: `${input.col}:${input.text}`, offset: 0, glyph: input.customGlyph }],
+    });
+    return;
+  }
+  input.runs.push({ ...baseRun, renderKind: "text" });
 }
 
 function cellIntersectsSelection(input: {
@@ -149,9 +193,11 @@ function buildRowModel(input: {
     const text = cell.char || " ";
     const resolvedStyle = input.resolver.resolve(cell);
     const cellCount = terminalCellCount(input.cells, col, text);
+    const customGlyph = resolveTerminalCustomGlyph(text);
     const selection = input.selection;
     let styleKey = resolvedStyle.key;
     let style = resolvedStyle.style;
+    let foregroundColor = resolvedStyle.foregroundColor;
     if (
       selection &&
       cellIntersectsSelection({
@@ -167,6 +213,7 @@ function buildRowModel(input: {
         foregroundColor: selection.foregroundColor,
         backgroundColor: selection.backgroundColor,
       });
+      foregroundColor = selection.foregroundColor;
     }
     appendRun({
       runs,
@@ -174,11 +221,14 @@ function buildRowModel(input: {
       cellCount,
       styleKey,
       style,
+      foregroundColor,
+      customGlyph,
       col,
     });
     hash = hashStringPart(hash, text);
     hash = hashStringPart(hash, String(cellCount));
     hash = hashStringPart(hash, styleKey);
+    hash = hashStringPart(hash, customGlyph ? "custom-glyph" : "text");
 
     if (cellCount > 1) {
       col += 1;

packages/app/src/terminal/native-renderer/terminal-selection.test.ts

@@ -276,6 +276,26 @@ describe("native terminal selection", () => {
     expect(copied).toEqual(["COPY_OK_123"]);
   });
 
+  it("copies custom-drawn Claude glyphs as their original Unicode text", async () => {
+    const terminal = createNativeHeadlessTerminal({ rows: 4, cols: 32, scrollbackLines: 20 });
+    const art = "╭─ Claude ─╮\r\n│ ▐▛███▜▌ │\r\n╰──────────╯";
+    await terminal.write(art);
+    const bounds = terminal.getBufferBounds();
+    const firstRow = rowWithText(terminal, "╭─ Claude ─╮");
+    const lastRow = rowWithText(terminal, "╰──────────╯");
+
+    expect(
+      extractTerminalSelectedText({
+        terminal,
+        selection: {
+          start: { row: firstRow, col: 0 },
+          end: { row: lastRow, col: 11 },
+          coordinateEpoch: bounds.coordinateEpoch,
+        },
+      }),
+    ).toBe(art.replaceAll("\r", ""));
+  });
+
   it("copies known text after it has scrolled into retained history", async () => {
     const terminal = createNativeHeadlessTerminal({ rows: 4, cols: 16, scrollbackLines: 20 });
     await terminal.write("KEEP_THIS_LINE\r\n");