54 lines
1.5 KiB
TypeScript
54 lines
1.5 KiB
TypeScript
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class CanvasController {
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private canvas: HTMLCanvasElement;
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private canvasDiv: HTMLDivElement;
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private ctx: CanvasRenderingContext2D | null;
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private isMouseDown: boolean = false;
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private x: number = 0;
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private y: number = 0;
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constructor() {
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this.canvas = document.createElement("canvas");
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this.canvasDiv = document.querySelector("#canvas") as HTMLDivElement;
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this.canvasDiv.appendChild(this.canvas);
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this.canvas.width = this.canvas.offsetWidth;
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this.canvas.height = this.canvas.offsetHeight;
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this.ctx = this.canvas.getContext("2d");
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// Events
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this.canvasDiv.addEventListener("mousedown", e => this.onMouseDown(e));
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this.canvasDiv.addEventListener("mouseup", () => this.onMouseUp());
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this.canvasDiv.addEventListener("mousemove", e => this.onMouseMove(e));
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}
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onMouseDown(event: MouseEvent) {
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this.isMouseDown = true;
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this.x = event.clientX;
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this.y = event.clientY;
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}
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onMouseUp() {
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this.isMouseDown = false;
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}
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onMouseMove(event: MouseEvent) {
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if (!this.isMouseDown || !this.ctx) {
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return;
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}
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this.ctx.beginPath();
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this.ctx.moveTo(this.x, this.y);
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this.ctx.lineTo(event.clientX, event.clientY);
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this.ctx.lineWidth = 1;
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this.ctx.stroke();
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this.x = event.clientX;
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this.y = event.clientY;
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}
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}
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const app = new CanvasController();
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export { app };
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