offscreen-example-a.js

/* title: Offscreen rendering. files: ../point_src/core/head.js ../point_src/pointpen.js ../point_src/pointdraw.js ../point_src/math.js ../point_src/extras.js ../point_src/point-content.js ../point_src/pointlist.js ../point_src/pointlistpen.js ../point_src/point.js ../point_src/stage.js ../point_src/offscreen.js mouse dragging stroke --- Use the `copyToOnScreen` function to copy an offscreen canvas to the onscreen canvas. However we see when applied, offscreen canvas image is distorted due to a dimensions mismatch */ class MainStageOffScreenContext extends Stage { /* In this format we Install an "offscreen canvas" as the primary rendering unit. the `copyToOnScreen` copies the offScreen canvas into the visible onscreen canvas. */ // canvas = document.getElementById('playspace'); canvas = 'playspace' // canvas = new OffscreenCanvas(500, 400) mounted(){ // this.canvas = new OffscreenCanvas(500, 400) // this.canvas = this.canvas.transferControlToOffscreen() this.offScreenCanvas = new OffscreenCanvas(500, 400) this._ctx = this.offScreenCanvas.getContext('2d') // this.onScreenCanvas = document.getElementById("playspace")//.getContext("2d"); this.point = new Point(10, 10) } // resolveCanvas() {} // stickCanvasSize(canvas){ // const onScreenCanvas = document.getElementById("playspace")//.getContext("2d"); // onScreenCanvas.width = 300 // onScreenCanvas.height = 200 // return // } draw(ctx){ var context = this.offScreenCanvas.getContext("2d"); // this.clear(ctx) context.fillStyle = '#444'; //set fill color context.fillRect(10, 10, 40, 40); (new Point(20,20,20)).pen.indicator(context) this.point.rotation += 1 this.point.pen.indicator(ctx) copyToOnScreen(this.offScreenCanvas, this.canvas) } } stage = MainStageOffScreenContext.go()