feat(tools): add brush controls

commands/ids.ts

@@ -22,6 +22,7 @@ export const commandIds = {
   selectionClear: "selection.clear",
   selectionAddLayer: "selection.addLayer",
   toolSetActive: "tool.setActive",
+  toolSetBrushSettings: "tool.setBrushSettings",
   toolEnterTemporaryPan: "tool.enterTemporaryPan",
   toolExitTemporaryPan: "tool.exitTemporaryPan",
   transformBegin: "transform.begin",

commands/index.ts

@@ -50,10 +50,10 @@ export type { CommandRegistry } from "./registry";
 export { createCommandRegistry } from "./registry";
 export { selectionAddLayerCommand, selectionClearCommand, selectionCommands, selectionSetCommand } from "./selection";
 export type { SelectionAddLayerPayload, SelectionSetPayload } from "./selection";
-export { toolCommands, toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand, toolSetActiveCommand } from "./tool";
+export { toolCommands, toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand, toolSetActiveCommand, toolSetBrushSettingsCommand } from "./tool";
 export { transformBeginCommand, transformCommands, transformEndCommand, transformSetBoundsCommand, transformUpdateCommand } from "./transform";
 export type { TransformBeginPayload, TransformSetBoundsPayload, TransformUpdatePayload } from "./transform";
-export type { ToolSetActivePayload } from "./tool";
+export type { ToolSetActivePayload, ToolSetBrushSettingsPayload } from "./tool";
 export {
   viewportCommands,
   viewportPanCommand,

commands/payloads.ts

@@ -21,7 +21,7 @@ import type {
   DocumentUngroupLayerPayload,
 } from "./document";
 import type { SelectionAddLayerPayload, SelectionSetPayload } from "./selection";
-import type { ToolSetActivePayload } from "./tool";
+import type { ToolSetActivePayload, ToolSetBrushSettingsPayload } from "./tool";
 import type { TransformBeginPayload, TransformSetBoundsPayload, TransformUpdatePayload } from "./transform";
 import type {
   ViewportFitArtboardPayload,
@@ -55,6 +55,7 @@ export type CommandPayloads = {
   [commandIds.selectionClear]: void;
   [commandIds.selectionAddLayer]: SelectionAddLayerPayload;
   [commandIds.toolSetActive]: ToolSetActivePayload;
+  [commandIds.toolSetBrushSettings]: ToolSetBrushSettingsPayload;
   [commandIds.toolEnterTemporaryPan]: void;
   [commandIds.toolExitTemporaryPan]: void;
   [commandIds.transformBegin]: TransformBeginPayload;

commands/tool.test.ts

@@ -1,11 +1,17 @@
 import { describe, expect, test } from "bun:test";
 import { createInitialAppState } from "@editor/initial-state";
-import { toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand, toolSetActiveCommand } from "./tool";
+import { toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand, toolSetActiveCommand, toolSetBrushSettingsCommand } from "./tool";
 
 describe("tool commands", () => {
   test("sets active tool", () => {
     const next = toolSetActiveCommand.execute({ state: createInitialAppState("Test") }, { tool: "crop" });
-    expect(next.editor.tools).toEqual({ activeTool: "crop", interactionMode: { type: "tool", tool: "crop" } });
+    expect(next.editor.tools).toEqual({ activeTool: "crop", interactionMode: { type: "tool", tool: "crop" }, brush: { color: "#111827", size: 8, hardness: 100 } });
+  });
+
+  test("sets brush settings", () => {
+    const next = toolSetBrushSettingsCommand.execute({ state: createInitialAppState("Test") }, { color: "#ff0000", size: 24, hardness: 50 });
+
+    expect(next.editor.tools.brush).toEqual({ color: "#ff0000", size: 24, hardness: 50 });
   });
 
   test("enters and exits temporary pan", () => {
@@ -13,7 +19,7 @@ describe("tool commands", () => {
     const panning = toolEnterTemporaryPanCommand.execute({ state: initial }, undefined);
     const restored = toolExitTemporaryPanCommand.execute({ state: panning }, undefined);
 
-    expect(panning.editor.tools).toEqual({ activeTool: "select", interactionMode: { type: "temporary-pan", previousTool: "select" } });
+    expect(panning.editor.tools).toEqual({ activeTool: "select", interactionMode: { type: "temporary-pan", previousTool: "select" }, brush: { color: "#111827", size: 8, hardness: 100 } });
     expect(restored.editor.tools).toEqual(initial.editor.tools);
   });
 });

commands/tool.ts

@@ -1,4 +1,4 @@
-import type { ToolId } from "@editor/tools";
+import type { BrushSettings, ToolId } from "@editor/tools";
 import type { Command } from "./command";
 import { commandIds } from "./ids";
 
@@ -6,6 +6,8 @@ export type ToolSetActivePayload = {
   tool: ToolId;
 };
 
+export type ToolSetBrushSettingsPayload = Partial<BrushSettings>;
+
 export const toolSetActiveCommand: Command<ToolSetActivePayload> = {
   id: commandIds.toolSetActive,
   name: "Set active tool",
@@ -15,6 +17,7 @@ export const toolSetActiveCommand: Command<ToolSetActivePayload> = {
       editor: {
         ...state.editor,
         tools: {
+          ...state.editor.tools,
           activeTool: payload.tool,
           interactionMode: { type: "tool", tool: payload.tool },
         },
@@ -23,6 +26,27 @@ export const toolSetActiveCommand: Command<ToolSetActivePayload> = {
   },
 };
 
+export const toolSetBrushSettingsCommand: Command<ToolSetBrushSettingsPayload> = {
+  id: commandIds.toolSetBrushSettings,
+  name: "Set brush settings",
+  execute({ state }, payload) {
+    return {
+      ...state,
+      editor: {
+        ...state.editor,
+        tools: {
+          ...state.editor.tools,
+          brush: {
+            color: payload.color ?? state.editor.tools.brush.color,
+            size: clampNumber(payload.size ?? state.editor.tools.brush.size, 1, 200),
+            hardness: clampNumber(payload.hardness ?? state.editor.tools.brush.hardness, 0, 100),
+          },
+        },
+      },
+    };
+  },
+};
+
 export const toolEnterTemporaryPanCommand: Command = {
   id: commandIds.toolEnterTemporaryPan,
   name: "Enter temporary pan",
@@ -54,6 +78,7 @@ export const toolExitTemporaryPanCommand: Command = {
       editor: {
         ...state.editor,
         tools: {
+          ...state.editor.tools,
           activeTool: mode.previousTool,
           interactionMode: { type: "tool", tool: mode.previousTool },
         },
@@ -62,4 +87,9 @@ export const toolExitTemporaryPanCommand: Command = {
   },
 };
 
-export const toolCommands = [toolSetActiveCommand, toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand] satisfies Command<unknown>[];
+export const toolCommands = [toolSetActiveCommand, toolSetBrushSettingsCommand, toolEnterTemporaryPanCommand, toolExitTemporaryPanCommand] satisfies Command<unknown>[];
+
+function clampNumber(value: number, min: number, max: number) {
+  if (!Number.isFinite(value)) return min;
+  return Math.max(min, Math.min(max, value));
+}

editor/tools.ts

@@ -6,14 +6,22 @@ export type InteractionMode =
   | { type: "tool"; tool: ToolId }
   | { type: "temporary-pan"; previousTool: ToolId };
 
+export type BrushSettings = {
+  color: string;
+  size: number;
+  hardness: number;
+};
+
 export type ToolState = {
   activeTool: ToolId;
   interactionMode: InteractionMode;
+  brush: BrushSettings;
 };
 
 export const initialToolState: ToolState = {
   activeTool: "select",
   interactionMode: { type: "tool", tool: "select" },
+  brush: { color: "#111827", size: 8, hardness: 100 },
 };
 
 export function isPanInteractionMode(interactionMode: InteractionMode): boolean {

input/transform-controls.test.ts

@@ -27,7 +27,7 @@ describe("transform controls input", () => {
         ...createInitialAppState("Test").editor,
         viewport: { center: { x: 0, y: 0 }, zoom: 1, rotation: 0, size: { w: 200, h: 200 } },
         selection: { artboardId: "a1", layerIds: [] },
-        tools: { activeTool: "select" as const, interactionMode: { type: "temporary-pan" as const, previousTool: "select" as const } },
+        tools: { activeTool: "select" as const, interactionMode: { type: "temporary-pan" as const, previousTool: "select" as const }, brush: { color: "#111827", size: 8, hardness: 100 } },
       },
     };
     const dispatched: unknown[] = [];
@@ -55,7 +55,7 @@ describe("transform controls input", () => {
         ...createInitialAppState("Test").editor,
         viewport: { center: { x: 0, y: 0 }, zoom: 1, rotation: 0, size: { w: 200, h: 200 } },
         selection: { artboardId: "a1", layerIds: [] },
-        tools: { activeTool: "crop" as const, interactionMode: { type: "tool" as const, tool: "crop" as const } },
+        tools: { activeTool: "crop" as const, interactionMode: { type: "tool" as const, tool: "crop" as const }, brush: { color: "#111827", size: 8, hardness: 100 } },
       },
     };
     const dispatched: unknown[] = [];

view/App.tsx

@@ -81,8 +81,10 @@ export function App({ app }: AppProps) {
       <div className="absolute inset-x-0 bottom-4 z-10 flex justify-center">
         <BottomControlsIsland
           viewport={state.editor.viewport}
-          visible={Boolean(transformBounds) || viewportActivityIsland.visible}
+          visible={state.editor.tools.activeTool === "brush" || state.editor.tools.activeTool === "eraser" || Boolean(transformBounds) || viewportActivityIsland.visible}
           action={viewportActivityIsland.action}
+          activeTool={state.editor.tools.activeTool}
+          brushSettings={state.editor.tools.brush}
           transformBounds={viewportActivityIsland.visible ? undefined : transformBounds}
           transformTarget={viewportActivityIsland.visible ? undefined : transformTarget}
           dispatch={app.store.dispatch}

view/BottomControlsIsland.tsx

@@ -1,5 +1,7 @@
 import type { AppStore } from "@editor/store";
 import type { ViewportState } from "@editor/state";
+import type { BrushSettings, ToolId } from "@editor/tools";
+import { BrushControls } from "./bottom-controls/BrushControls";
 import { PanControls } from "./bottom-controls/PanControls";
 import { TransformControls } from "./bottom-controls/TransformControls";
 import { ZoomControls } from "./bottom-controls/ZoomControls";
@@ -11,12 +13,14 @@ export type BottomControlsIslandProps = {
   viewport: ViewportState;
   visible: boolean;
   action: BottomControlsAction;
+  activeTool: ToolId;
+  brushSettings: BrushSettings;
   transformBounds?: Rect;
   transformTarget?: TransformTarget;
-  dispatch: AppStore["dispatch"];
+  dispatch: AppStore["dispatch"]; 
 };
 
-export function BottomControlsIsland({ viewport, visible, action, transformBounds, transformTarget, dispatch }: BottomControlsIslandProps) {
+export function BottomControlsIsland({ viewport, visible, action, activeTool, brushSettings, transformBounds, transformTarget, dispatch }: BottomControlsIslandProps) {
   const zoomPercent = Math.round(viewport.zoom * 100);
   const x = Math.round(viewport.center.x);
   const y = Math.round(viewport.center.y);
@@ -28,7 +32,9 @@ export function BottomControlsIsland({ viewport, visible, action, transformBound
         visible ? "pointer-events-auto translate-y-0 opacity-100" : "pointer-events-none translate-y-3 opacity-0"
       }`}
     >
-      {transformBounds && transformTarget ? (
+      {activeTool === "brush" || activeTool === "eraser" ? (
+        <BrushControls tool={activeTool} settings={brushSettings} dispatch={dispatch} />
+      ) : transformBounds && transformTarget ? (
         <TransformControls bounds={transformBounds} target={transformTarget} dispatch={dispatch} />
       ) : action === "pan" ? (
         <PanControls x={x} y={y} />

view/bottom-controls/BrushControls.tsx

@@ -0,0 +1,59 @@
+import { commandIds } from "@commands/ids";
+import type { AppStore } from "@editor/store";
+import type { BrushSettings, ToolId } from "@editor/tools";
+import { BottomControlDivider } from "./Divider";
+import { bottomControlLabelClass } from "./styles";
+
+export type BrushControlsProps = {
+  tool: Extract<ToolId, "brush" | "eraser">;
+  settings: BrushSettings;
+  dispatch: AppStore["dispatch"];
+};
+
+export function BrushControls({ tool, settings, dispatch }: BrushControlsProps) {
+  return (
+    <div className="flex w-full items-center justify-center gap-2 tabular-nums">
+      <span className="px-2 font-medium text-white/85">{tool === "eraser" ? "Eraser" : "Brush"}</span>
+      <BottomControlDivider />
+      {tool === "brush" ? (
+        <label className="flex items-center gap-1.5">
+          <span className={bottomControlLabelClass()}>Color</span>
+          <input
+            type="color"
+            className="h-7 w-8 cursor-pointer rounded border-0 bg-transparent p-0"
+            value={settings.color}
+            aria-label="Brush color"
+            onChange={(event) => dispatch(commandIds.toolSetBrushSettings, { color: event.target.value })}
+          />
+        </label>
+      ) : null}
+      <label className="flex items-center gap-1.5">
+        <span className={bottomControlLabelClass()}>Size</span>
+        <input
+          type="range"
+          min={1}
+          max={200}
+          value={settings.size}
+          className="w-24 accent-white"
+          aria-label={`${tool} size`}
+          onChange={(event) => dispatch(commandIds.toolSetBrushSettings, { size: Number(event.target.value) })}
+        />
+        <span className="w-8 text-right text-white">{Math.round(settings.size)}</span>
+      </label>
+      <BottomControlDivider />
+      <label className="flex items-center gap-1.5">
+        <span className={bottomControlLabelClass()}>Hard</span>
+        <input
+          type="range"
+          min={0}
+          max={100}
+          value={settings.hardness}
+          className="w-24 accent-white"
+          aria-label={`${tool} hardness`}
+          onChange={(event) => dispatch(commandIds.toolSetBrushSettings, { hardness: Number(event.target.value) })}
+        />
+        <span className="w-8 text-right text-white">{Math.round(settings.hardness)}</span>
+      </label>
+    </div>
+  );
+}

view/canvas/brush.ts

@@ -25,8 +25,9 @@ export async function updateBrushSession(options: {
   store: AppStore;
   session: BrushSession;
   point: Vec2D;
-  color?: string;
-  size?: number;
+  color: string;
+  size: number;
+  hardness: number;
 }): Promise<BrushSession> {
   const state = options.store.getState();
   const layer = findRasterLayer(state.document.artboards.flatMap((artboard) => artboard.layers), options.session.layerId);
@@ -41,8 +42,9 @@ export async function updateBrushSession(options: {
     height: asset.intrinsicSize.h,
     from: documentPointToAssetPoint(options.session.previousPoint, layer, asset.intrinsicSize.w, asset.intrinsicSize.h),
     to: documentPointToAssetPoint(options.point, layer, asset.intrinsicSize.w, asset.intrinsicSize.h),
-    color: options.color ?? "#111827",
-    size: options.size ?? 8,
+    color: options.color,
+    size: options.size,
+    hardness: options.hardness,
     mode: options.session.mode,
   });
 
@@ -65,6 +67,7 @@ async function drawStroke(options: {
   to: Vec2D;
   color: string;
   size: number;
+  hardness: number;
   mode: "brush" | "eraser";
 }) {
   const canvas = document.createElement("canvas");
@@ -75,8 +78,11 @@ async function drawStroke(options: {
 
   const image = await loadImage(options.source);
   context.drawImage(image, 0, 0, canvas.width, canvas.height);
+  const hardness = Math.max(0, Math.min(100, options.hardness)) / 100;
   context.globalCompositeOperation = options.mode === "eraser" ? "destination-out" : "source-over";
   context.strokeStyle = options.color;
+  context.shadowColor = options.mode === "eraser" ? "rgba(0,0,0,1)" : options.color;
+  context.shadowBlur = (1 - hardness) * options.size;
   context.lineWidth = options.size;
   context.lineCap = "round";
   context.lineJoin = "round";

view/canvas/useCanvasInput.ts

@@ -103,7 +103,8 @@ export function useCanvasInput(
       if (brushSession.current) {
         const activeSessionId = brushSessionId.current;
         const point = viewportPointToDocumentPoint(inputEvent.position, store.getState().editor.viewport);
-        void updateBrushSession({ store, session: brushSession.current, point }).then((nextSession) => {
+        const settings = store.getState().editor.tools.brush;
+        void updateBrushSession({ store, session: brushSession.current, point, color: settings.color, size: settings.size, hardness: settings.hardness }).then((nextSession) => {
           if (brushSessionId.current === activeSessionId) brushSession.current = nextSession;
         });
         event.preventDefault();