add board

editor/src/Canvas.tsx

@@ -1,6 +1,6 @@
-import { useEffect, useRef, type ReactElement, type RefObject } from "react";
+import { useEffect, type ReactElement, type RefObject } from "react";
 import { type Editor } from "./editor/Editor";
-import { V2 } from "./editor/Cx";
+import { V2 } from "./editor/V2";
 
 type Props = { editor: Editor; canvasRef: RefObject<HTMLCanvasElement | null> };
 
@@ -31,7 +31,9 @@ function Canvas({ editor, canvasRef }: Props): ReactElement {
             editor.renderIfNeeded(ev.target as HTMLCanvasElement);
           }}
           onMouseMove={(ev) => {
-            editor.mouseMove(V2(ev.movementX, ev.movementY));
+            const deltaPos = V2(ev.movementX, ev.movementY);
+            const pos = V2(ev.nativeEvent.offsetX, ev.nativeEvent.offsetY);
+            editor.mouseMove(deltaPos, pos);
             editor.renderIfNeeded(ev.target as HTMLCanvasElement);
           }}
           onKeyDown={(ev) => {

editor/src/editor/Board.ts

@@ -0,0 +1,59 @@
+import { rectsCollide, type V2 } from "./V2";
+
+export class Board {
+  private components: Component[] = [];
+
+  canPlaceComponent(pos: V2, size: V2): boolean {
+    return !this.components.some((comp) =>
+      rectsCollide(comp.pos, comp.size, pos, size),
+    );
+  }
+
+  placeComponent(pos: V2, size: V2, label: string) {
+    this.components.push({ pos, size, label });
+  }
+
+  render(
+    canvas: HTMLCanvasElement,
+    c: CanvasRenderingContext2D,
+    offset: V2,
+    gridSize: Readonly<V2>,
+  ) {
+    for (const comp of this.components) {
+      const {
+        pos: { x, y },
+        size: { x: w, y: h },
+      } = comp;
+
+      c.fillStyle = `#0088cc`;
+      c.fillRect(
+        x * gridSize.x + offset.x,
+        y * gridSize.y + offset.y,
+        w * gridSize.x,
+        h * gridSize.y,
+      );
+      c.strokeStyle = `#333333`;
+      c.lineWidth = 2;
+      c.strokeRect(
+        x * gridSize.x + offset.x,
+        y * gridSize.y + offset.y,
+        w * gridSize.x,
+        h * gridSize.y,
+      );
+      c.fillStyle = `#333333`;
+      c.font = "bold 16px monospace";
+      const textMetrix = c.measureText(comp.label);
+      c.fillText(
+        comp.label,
+        x * gridSize.x + offset.x + (w * gridSize.x) / 2 - textMetrix.width / 2,
+        y * gridSize.y + offset.y + 13 + (h * gridSize.y) / 2 - 16 / 2,
+      );
+    }
+  }
+}
+
+type Component = {
+  pos: V2;
+  size: V2;
+  label: string;
+};

editor/src/editor/Cx.ts

@@ -1,12 +1,20 @@
+import { Board } from "./Board";
 import type { State } from "./State";
 import { Normal } from "./states/Normal";
+import { V2 } from "./V2";
 
 export class Cx {
   private offset = V2(0, 0);
   private renderNeeded = false;
   private state = new Normal(this) as State;
   private updateActions: (() => void)[] = [];
+
+  public gridSize = Object.freeze(V2(20, 20));
+
   private selectionRect: SelectionRect | null = null;
+  private componentPlacer: ComponentPlacer | null = null;
+
+  public board = new Board();
 
   render(canvas: HTMLCanvasElement) {
     const c = canvas.getContext("2d")!;
@@ -15,7 +23,7 @@ export class Cx {
     c.fillStyle = "#666";
     c.fillRect(0, 0, canvas.width, canvas.height);
 
-    const gridSize = { x: 20, y: 20 };
+    const gridSize = this.gridSize;
     const dotSize = { x: 2, y: 2 };
 
     c.fillStyle = "#111";
@@ -30,6 +38,8 @@ export class Cx {
       }
     }
 
+    this.board.render(canvas, c, this.offset, gridSize);
+
     if (this.selectionRect) {
       const {
         pos: { x, y },
@@ -42,6 +52,17 @@ export class Cx {
       c.lineWidth = 2;
       c.strokeRect(x, y, w, h);
     }
+
+    if (this.componentPlacer) {
+      const {
+        pos: { x, y },
+        size: { x: w, y: h },
+      } = this.componentPlacer;
+
+      c.strokeStyle = `#ffffff`;
+      c.lineWidth = 2;
+      c.strokeRect(x - (x % gridSize.x), y - (y % gridSize.y), w, h);
+    }
   }
 
   renderIfNeeded(canvas: HTMLCanvasElement) {
@@ -57,8 +78,8 @@ export class Cx {
   mouseUp(pos: V2) {
     this.state.onMouseUp?.(pos);
   }
-  mouseMove(deltaPos: V2) {
+  mouseMove(deltaPos: V2, pos: V2) {
-    this.state.onMouseMove?.(deltaPos);
+    this.state.onMouseMove?.(deltaPos, pos);
   }
   keyDown(key: string) {
     this.state.onKeyDown?.(key);
@@ -67,6 +88,12 @@ export class Cx {
     this.state.onKeyUp?.(key);
   }
   selectTool(tool: Tool) {
+    // this is very much a hack so that other tools
+    // can be selected from any tool, without me
+    // having to add that in every state.
+    if (!(this.state instanceof Normal)) {
+      this.transitionTo(new Normal(this));
+    }
     this.state.selectTool?.(tool);
   }
   selectedTool(): Tool | null {
@@ -85,7 +112,9 @@ export class Cx {
   }
 
   transitionTo(newState: State) {
+    this.state.leaveState?.();
     this.state = newState;
+    this.state.enterState?.();
     this.notifyListeners();
   }
 
@@ -118,14 +147,42 @@ export class Cx {
       this.renderNeeded = true;
     }
   }
-}
 
-export type V2 = { x: number; y: number };
+  addComponentPlacer(pos: V2, size: V2) {
-export const V2 = (x: number, y: number): V2 => ({ x, y });
+    this.componentPlacer = { pos, size };
+    this.renderNeeded = true;
+  }
+
+  removeComponentPlacer() {
+    this.componentPlacer = null;
+    this.renderNeeded = true;
+  }
+
+  setComponentPlacerPos(pos: V2) {
+    if (this.componentPlacer) {
+      this.componentPlacer.pos = pos;
+      this.renderNeeded = true;
+    }
+  }
+
+  canvasPosToBoard(pos: V2): V2 {
+    const absX = pos.x - this.offset.x;
+    const absY = pos.y - this.offset.y;
+    return V2(
+      (absX - (absX % this.gridSize.x)) / this.gridSize.x,
+      (absY - (absY % this.gridSize.y)) / this.gridSize.y,
+    );
+  }
+}
 
 export type SelectionRect = {
   pos: V2;
   size: V2;
 };
 
+export type ComponentPlacer = {
+  pos: V2;
+  size: V2;
+};
+
 export type Tool = "select" | "pan" | "and";

editor/src/editor/Editor.ts

@@ -1,4 +1,5 @@
-import { Cx, V2, type Tool } from "./Cx";
+import { Cx, type Tool } from "./Cx";
+import { V2 } from "./V2";
 
 export class Editor {
   private cx = new Cx();
@@ -19,8 +20,8 @@ export class Editor {
     this.cx.mouseUp(pos);
   }
 
-  mouseMove(deltaPos: V2) {
+  mouseMove(deltaPos: V2, pos: V2) {
-    this.cx.mouseMove(deltaPos);
+    this.cx.mouseMove(deltaPos, pos);
   }
 
   keyDown(key: string) {

editor/src/editor/State.ts

@@ -1,9 +1,12 @@
-import type { V2, Tool } from "./Cx";
+import type { Tool } from "./Cx";
+import type { V2 } from "./V2";
 
 export interface State {
+  enterState?(): void;
+  leaveState?(): void;
   onMouseDown?(pos: V2): void;
   onMouseUp?(pos: V2): void;
-  onMouseMove?(deltaPos: V2): void;
+  onMouseMove?(deltaPos: V2, pos: V2): void;
   onKeyDown?(key: string): void;
   onKeyUp?(key: string): void;
   selectTool?(tool: Tool): void;

editor/src/editor/V2.ts

@@ -0,0 +1,11 @@
+export type V2 = { x: number; y: number };
+export const V2 = (x: number, y: number): V2 => ({ x, y });
+
+export function rectsCollide(
+  { x: ax, y: ay }: V2,
+  { x: aw, y: ah }: V2,
+  { x: bx, y: by }: V2,
+  { x: bw, y: bh }: V2,
+): boolean {
+  return ax < bx + bw && ax + aw > bx && ay < by + bh && ay + ah > by;
+}

editor/src/editor/states/Normal.ts

@@ -1,4 +1,5 @@
-import type { Cx, Tool, V2 } from "../Cx";
+import type { Cx, Tool } from "../Cx";
+import type { V2 } from "../V2";
 import type { State } from "../State";
 import { Panning } from "./Panning";
 import { Placing } from "./Placing";

editor/src/editor/states/Panning.ts

@@ -1,4 +1,5 @@
-import type { Cx, Tool, V2 } from "../Cx";
+import type { Cx, Tool } from "../Cx";
+import type { V2 } from "../V2";
 import type { State } from "../State";
 import { Normal } from "./Normal";
 
@@ -35,11 +36,6 @@ export class Panning implements State {
     }
   }
 
-  selectTool(tool: Tool): void {
-    this.cx.transitionTo(new Normal(this.cx));
-    this.cx.selectTool(tool);
-  }
-
   selectedTool(): Tool | null {
     return "pan";
   }

editor/src/editor/states/Placing.ts

@@ -1,4 +1,5 @@
-import type { Cx, Tool, V2 } from "../Cx";
+import { type Cx, type Tool } from "../Cx";
+import { V2 } from "../V2";
 import type { State } from "../State";
 import { Normal } from "./Normal";
 
@@ -8,9 +9,25 @@ export class Placing implements State {
     private tool: Tool,
   ) {}
 
-  onMouseUp(pos: V2): void {
+  enterState(): void {
-    this.cx.transitionTo(new Normal(this.cx));
+    this.cx.addComponentPlacer(V2(0, 0), V2(20 * 4, 20 * 2));
-    console.log("place");
+  }
+
+  leaveState(): void {
+    this.cx.removeComponentPlacer();
+  }
+
+  onMouseDown(pos: V2): void {
+    const boardPos = this.cx.canvasPosToBoard(pos);
+    if (this.cx.board.canPlaceComponent(boardPos, V2(4, 2))) {
+      console.log("place");
+      this.cx.board.placeComponent(boardPos, V2(4, 2), "AND");
+      this.cx.transitionTo(new Normal(this.cx));
+    }
+  }
+
+  onMouseMove(_deltaPos: V2, pos: V2): void {
+    this.cx.setComponentPlacerPos(pos);
   }
 
   onKeyDown(key: string): void {

editor/src/editor/states/Selecting.ts

@@ -1,4 +1,5 @@
-import type { Cx, Tool, V2 } from "../Cx";
+import type { Cx, Tool } from "../Cx";
+import type { V2 } from "../V2";
 import type { State } from "../State";
 import { Normal } from "./Normal";