| <!DOCTYPE html> |
| <title>CanvasKit (Skia via Web Assembly)</title> |
| <meta charset="utf-8" /> |
| <meta http-equiv="X-UA-Compatible" content="IE=edge"> |
| <meta name="viewport" content="width=device-width, initial-scale=1.0"> |
| |
| <style> |
| canvas, img { |
| border: 1px dashed #AAA; |
| } |
| #api5_c, #api6_c { |
| width: 300px; |
| height: 300px; |
| } |
| |
| </style> |
| |
| <h2>Drop in replacement for HTML Canvas (e.g. node.js)</h2> |
| <img id=api1 width=300 height=300> |
| <canvas id=api1_c width=300 height=300></canvas> |
| <img id=api2 width=300 height=300> |
| <canvas id=api2_c width=300 height=300></canvas> |
| <img id=api3 width=300 height=300> |
| <canvas id=api3_c width=300 height=300></canvas> |
| <img id=api4 width=300 height=300> |
| <canvas id=api4_c width=300 height=300></canvas> |
| <img id=api5 width=300 height=300> |
| <canvas id=api5_c width=300 height=300></canvas> |
| <img id=api6 width=300 height=300> |
| <canvas id=api6_c width=300 height=300></canvas> |
| <img id=api7 width=300 height=300> |
| <canvas id=api7_c width=300 height=300></canvas> |
| <img id=api8 width=300 height=300> |
| <canvas id=api8_c width=300 height=300></canvas> |
| |
| <h2> CanvasKit expands the functionality of a stock HTML canvas</h2> |
| <canvas id=vertex1 width=300 height=300></canvas> |
| <canvas id=gradient1 width=300 height=300></canvas> |
| <canvas id=patheffect width=300 height=300></canvas> |
| <canvas id=paths width=200 height=200></canvas> |
| <canvas id=pathperson width=300 height=300></canvas> |
| <canvas id=ink width=300 height=300></canvas> |
| <canvas id=surfaces width=300 height=300></canvas> |
| <canvas id=atlas width=300 height=300></canvas> |
| <canvas id=decode width=300 height=300></canvas> |
| |
| <h2> CanvasKit can allow for text measurement/placement (e.g. breaking, kerning)</h2> |
| <canvas id=textonpath width=300 height=300></canvas> |
| <canvas id=drawGlyphs width=300 height=300></canvas> |
| |
| <h2> Interactive drawPatch</h2> |
| <canvas id=interdrawpatch width=512 height=512></canvas> |
| |
| <script type="text/javascript" src="/node_modules/canvaskit/bin/canvaskit.js"></script> |
| |
| <script type="text/javascript" charset="utf-8"> |
| |
| var CanvasKit = null; |
| var cdn = 'https://storage.googleapis.com/skia-cdn/misc/'; |
| |
| const ckLoaded = CanvasKitInit({locateFile: (file) => '/node_modules/canvaskit/bin/'+file}); |
| |
| const loadRoboto = fetch(cdn + 'Roboto-Regular.ttf').then((response) => response.arrayBuffer()); |
| const loadNotoSerif = fetch(cdn + 'NotoSerif-Regular.ttf').then((response) => response.arrayBuffer()); |
| const loadTestImage = fetch(cdn + 'test.png').then((response) => response.arrayBuffer()); |
| |
| // Examples which only require canvaskit |
| ckLoaded.then((CK) => { |
| CanvasKit = CK; |
| PathExample(CanvasKit); |
| InkExample(CanvasKit); |
| PathPersonExample(CanvasKit); |
| VertexAPI1(CanvasKit); |
| GradiantAPI1(CanvasKit); |
| TextOnPathAPI1(CanvasKit); |
| DrawGlyphsAPI1(CanvasKit); |
| SurfaceAPI1(CanvasKit); |
| CanvasAPI1(CanvasKit); |
| CanvasAPI2(CanvasKit); |
| CanvasAPI3(CanvasKit); |
| CanvasAPI4(CanvasKit); |
| CanvasAPI5(CanvasKit); |
| CanvasAPI6(CanvasKit); |
| CanvasAPI7(CanvasKit); |
| CanvasAPI8(CanvasKit); |
| InteractivePatch(CanvasKit); |
| }); |
| |
| // Examples requiring external resources |
| Promise.all([ckLoaded, loadRoboto]).then((results) => {DrawingExample(...results)}); |
| Promise.all([ckLoaded, loadTestImage]).then((results) => {AtlasAPI1(...results)}); |
| Promise.all([ckLoaded, loadTestImage]).then((results) => {DecodeAPI(...results)}); |
| |
| function DrawingExample(CanvasKit, robotoData) { |
| if (!robotoData || !CanvasKit) { |
| return; |
| } |
| const surface = CanvasKit.MakeCanvasSurface('patheffect'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| |
| const paint = new CanvasKit.Paint(); |
| |
| const fontMgr = CanvasKit.FontMgr.RefDefault(); |
| const roboto = fontMgr.MakeTypefaceFromData(robotoData); |
| |
| const textPaint = new CanvasKit.Paint(); |
| textPaint.setColor(CanvasKit.RED); |
| textPaint.setAntiAlias(true); |
| |
| const textFont = new CanvasKit.Font(roboto, 30); |
| |
| let i = 0; |
| |
| let X = 128; |
| let Y = 128; |
| |
| function drawFrame(canvas) { |
| const path = starPath(CanvasKit, X, Y); |
| // Some animations see performance improvements by marking their |
| // paths as volatile. |
| path.setIsVolatile(true); |
| const dpe = CanvasKit.PathEffect.MakeDash([15, 5, 5, 10], i/5); |
| i++; |
| |
| paint.setPathEffect(dpe); |
| paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| paint.setStrokeWidth(5.0 + -3 * Math.cos(i/30)); |
| paint.setAntiAlias(true); |
| paint.setColor(CanvasKit.Color(66, 129, 164, 1.0)); |
| |
| canvas.clear(CanvasKit.TRANSPARENT); |
| |
| canvas.drawPath(path, paint); |
| canvas.drawText('Try Clicking!', 10, 280, textPaint, textFont); |
| |
| dpe.delete(); |
| path.delete(); |
| surface.requestAnimationFrame(drawFrame); |
| } |
| surface.requestAnimationFrame(drawFrame); |
| |
| // Make animation interactive |
| let interact = (e) => { |
| if (!e.pressure) { |
| return; |
| } |
| X = e.offsetX; |
| Y = e.offsetY; |
| }; |
| document.getElementById('patheffect').addEventListener('pointermove', interact); |
| document.getElementById('patheffect').addEventListener('pointerdown', interact); |
| preventScrolling(document.getElementById('patheffect')); |
| // A client would need to delete this if it didn't go on for ever. |
| // paint.delete(); |
| // textPaint.delete(); |
| // textFont.delete(); |
| } |
| |
| function InteractivePatch(CanvasKit) { |
| const ELEM = 'interdrawpatch'; |
| const surface = CanvasKit.MakeCanvasSurface(ELEM); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| |
| let live_corner, live_index; |
| |
| const paint = new CanvasKit.Paint(); |
| const pts_paint = new CanvasKit.Paint(); |
| pts_paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| pts_paint.setStrokeWidth(9); |
| pts_paint.setStrokeCap(CanvasKit.StrokeCap.Round); |
| |
| const line_paint = new CanvasKit.Paint(); |
| line_paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| line_paint.setStrokeWidth(2); |
| |
| const colors = [CanvasKit.RED, CanvasKit.BLUE, CanvasKit.YELLOW, CanvasKit.CYAN]; |
| |
| const patch = [ |
| [ 10,170, 10, 10, 170, 10], // prev_vector, point, next_vector |
| [340, 10, 500, 10, 500,170], |
| [500,340, 500,500, 340,500], |
| [170,500, 10,500, 10,340], |
| ]; |
| |
| function get_corner(corner, index) { |
| return [corner[index*2+0], corner[index*2+1]]; |
| } |
| |
| function push_xy(array, xy) { |
| array.push(xy[0], xy[1]); |
| } |
| |
| function patch_to_cubics(patch) { |
| const array = []; |
| push_xy(array, get_corner(patch[0],1)); |
| push_xy(array, get_corner(patch[0],2)); |
| for (let i = 1; i < 4; ++i) { |
| push_xy(array, get_corner(patch[i],0)); |
| push_xy(array, get_corner(patch[i],1)); |
| push_xy(array, get_corner(patch[i],2)); |
| } |
| push_xy(array, get_corner(patch[0],0)); |
| |
| return array; |
| } |
| |
| function drawFrame(canvas) { |
| const cubics = patch_to_cubics(patch); |
| |
| canvas.drawColor(CanvasKit.WHITE); |
| canvas.drawPatch(cubics, colors, null, null, paint); |
| if (live_corner) { |
| canvas.drawPoints(CanvasKit.PointMode.Polygon, live_corner, line_paint); |
| } |
| canvas.drawPoints(CanvasKit.PointMode.Points, cubics, pts_paint); |
| |
| surface.requestAnimationFrame(drawFrame); |
| } |
| |
| surface.requestAnimationFrame(drawFrame); |
| |
| function length2(x, y) { |
| return x*x + y*y; |
| } |
| function hit_test(x,y, x1,y1) { |
| return length2(x-x1, y-y1) <= 10*10; |
| } |
| function pointer_up(e) { |
| live_corner = null; |
| live_index = null; |
| } |
| |
| function pointer_down(e) { |
| live_corner = null; |
| live_index = null; |
| for (p of patch) { |
| for (let i = 0; i < 6; i += 2) { |
| if (hit_test(p[i], p[i+1], e.offsetX, e.offsetY)) { |
| live_corner = p; |
| live_index = i; |
| } |
| } |
| } |
| } |
| |
| function pointer_move(e) { |
| if (e.pressure && live_corner) { |
| if (live_index == 2) { |
| // corner |
| const dx = e.offsetX - live_corner[2]; |
| const dy = e.offsetY - live_corner[3]; |
| for (let i = 0; i < 3; ++i) { |
| live_corner[i*2+0] += dx; |
| live_corner[i*2+1] += dy; |
| } |
| } else { |
| // control-point |
| live_corner[live_index+0] = e.offsetX; |
| live_corner[live_index+1] = e.offsetY; |
| } |
| } |
| } |
| document.getElementById(ELEM).addEventListener('pointermove', pointer_move); |
| document.getElementById(ELEM).addEventListener('pointerdown', pointer_down); |
| document.getElementById(ELEM).addEventListener('pointerup', pointer_up); |
| preventScrolling(document.getElementById(ELEM)); |
| } |
| |
| function PathPersonExample(CanvasKit) { |
| const surface = CanvasKit.MakeSWCanvasSurface('pathperson'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| |
| function drawFrame(canvas) { |
| const paint = new CanvasKit.Paint(); |
| paint.setStrokeWidth(1.0); |
| paint.setAntiAlias(true); |
| paint.setColor(CanvasKit.Color(0, 0, 0, 1.0)); |
| paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| |
| const path = new CanvasKit.Path(); |
| path.moveTo(10, 10); |
| path.lineTo(100, 10); |
| path.moveTo(10, 10); |
| path.lineTo(10, 200); |
| path.moveTo(10, 100); |
| path.lineTo(100,100); |
| path.moveTo(10, 200); |
| path.lineTo(100, 200); |
| |
| canvas.drawPath(path, paint); |
| path.delete(); |
| paint.delete(); |
| } |
| // Intentionally just draw frame once |
| surface.drawOnce(drawFrame); |
| } |
| |
| function PathExample(CanvasKit) { |
| const surface = CanvasKit.MakeSWCanvasSurface('paths'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| |
| function drawFrame(canvas) { |
| const paint = new CanvasKit.Paint(); |
| paint.setStrokeWidth(1.0); |
| paint.setAntiAlias(true); |
| paint.setColor(CanvasKit.Color(0, 0, 0, 1.0)); |
| paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| |
| const path = new CanvasKit.Path(); |
| path.moveTo(20, 5); |
| path.lineTo(30, 20); |
| path.lineTo(40, 10); |
| path.lineTo(50, 20); |
| path.lineTo(60, 0); |
| path.lineTo(20, 5); |
| |
| path.moveTo(20, 80); |
| path.cubicTo(90, 10, 160, 150, 190, 10); |
| |
| path.moveTo(36, 148); |
| path.quadTo(66, 188, 120, 136); |
| path.lineTo(36, 148); |
| |
| path.moveTo(150, 180); |
| path.arcToTangent(150, 100, 50, 200, 20); |
| path.lineTo(160, 160); |
| |
| path.moveTo(20, 120); |
| path.lineTo(20, 120); |
| |
| canvas.drawPath(path, paint); |
| |
| const rrect = CanvasKit.RRectXY([100, 10, 140, 62], 10, 4); |
| |
| const rrectPath = new CanvasKit.Path().addRRect(rrect, true); |
| |
| canvas.drawPath(rrectPath, paint); |
| |
| rrectPath.delete(); |
| path.delete(); |
| paint.delete(); |
| } |
| // Intentionally just draw frame once |
| surface.drawOnce(drawFrame); |
| } |
| |
| function preventScrolling(canvas) { |
| canvas.addEventListener('touchmove', (e) => { |
| // Prevents touch events in the canvas from scrolling the canvas. |
| e.preventDefault(); |
| e.stopPropagation(); |
| }); |
| } |
| |
| function InkExample(CanvasKit) { |
| const surface = CanvasKit.MakeCanvasSurface('ink'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| |
| let paint = new CanvasKit.Paint(); |
| paint.setAntiAlias(true); |
| paint.setColor(CanvasKit.Color(0, 0, 0, 1.0)); |
| paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| paint.setStrokeWidth(4.0); |
| paint.setPathEffect(CanvasKit.PathEffect.MakeCorner(50)); |
| |
| // Draw I N K |
| let path = new CanvasKit.Path(); |
| path.moveTo(80, 30); |
| path.lineTo(80, 80); |
| |
| path.moveTo(100, 80); |
| path.lineTo(100, 15); |
| path.lineTo(130, 95); |
| path.lineTo(130, 30); |
| |
| path.moveTo(150, 30); |
| path.lineTo(150, 80); |
| path.moveTo(170, 30); |
| path.lineTo(150, 55); |
| path.lineTo(170, 80); |
| |
| let paths = [path]; |
| let paints = [paint]; |
| |
| function drawFrame(canvas) { |
| canvas.clear(CanvasKit.Color(255, 255, 255, 1.0)); |
| |
| for (let i = 0; i < paints.length && i < paths.length; i++) { |
| canvas.drawPath(paths[i], paints[i]); |
| } |
| |
| surface.requestAnimationFrame(drawFrame); |
| } |
| |
| let hold = false; |
| let interact = (e) => { |
| let type = e.type; |
| if (type === 'lostpointercapture' || type === 'pointerup' || !e.pressure ) { |
| hold = false; |
| return; |
| } |
| if (hold) { |
| path.lineTo(e.offsetX, e.offsetY); |
| } else { |
| paint = paint.copy(); |
| paint.setColor(CanvasKit.Color(Math.random() * 255, Math.random() * 255, Math.random() * 255, Math.random() + .2)); |
| paints.push(paint); |
| path = new CanvasKit.Path(); |
| paths.push(path); |
| path.moveTo(e.offsetX, e.offsetY); |
| } |
| hold = true; |
| }; |
| document.getElementById('ink').addEventListener('pointermove', interact); |
| document.getElementById('ink').addEventListener('pointerdown', interact); |
| document.getElementById('ink').addEventListener('lostpointercapture', interact); |
| document.getElementById('ink').addEventListener('pointerup', interact); |
| preventScrolling(document.getElementById('ink')); |
| surface.requestAnimationFrame(drawFrame); |
| } |
| |
| function starPath(CanvasKit, X=128, Y=128, R=116) { |
| let p = new CanvasKit.Path(); |
| p.moveTo(X + R, Y); |
| for (let i = 1; i < 8; i++) { |
| let a = 2.6927937 * i; |
| p.lineTo(X + R * Math.cos(a), Y + R * Math.sin(a)); |
| } |
| return p; |
| } |
| |
| function CanvasAPI1(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api1_c'); |
| |
| let skPromise = fetch(cdn + 'test.png') |
| // if clients want to use a Blob, they are responsible |
| // for reading it themselves. |
| .then((response) => response.arrayBuffer()) |
| .then((buffer) => { |
| skcanvas._img = skcanvas.decodeImage(buffer); |
| }); |
| let realPromise = fetch(cdn + 'test.png') |
| .then((response) => response.blob()) |
| .then((blob) => createImageBitmap(blob)) |
| .then((bitmap) => { |
| realCanvas._img = bitmap; |
| }); |
| |
| let realFontLoaded = new FontFace('Bungee', 'url(/tests/assets/Bungee-Regular.ttf)', { |
| 'family': 'Bungee', |
| 'style': 'normal', |
| 'weight': '400', |
| }).load().then((font) => { |
| document.fonts.add(font); |
| }); |
| |
| let skFontLoaded = fetch('/tests/assets/Bungee-Regular.ttf').then( |
| (response) => response.arrayBuffer()).then( |
| (buffer) => { |
| // loadFont is synchronous |
| skcanvas.loadFont(buffer, { |
| 'family': 'Bungee', |
| 'style': 'normal', |
| 'weight': '400', |
| }); |
| }); |
| |
| Promise.all([realPromise, skPromise, realFontLoaded, skFontLoaded]).then(() => { |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.fillStyle = '#EEE'; |
| ctx.fillRect(0, 0, 300, 300); |
| ctx.fillStyle = 'black'; |
| ctx.font = '26px Bungee'; |
| ctx.rotate(.1); |
| ctx.fillText('Awesome ', 25, 100); |
| ctx.strokeText('Groovy!', 200, 100); |
| |
| // Draw line under Awesome |
| ctx.strokeStyle = 'rgba(125,0,0,0.5)'; |
| ctx.beginPath(); |
| ctx.lineWidth = 6; |
| ctx.moveTo(25, 105); |
| ctx.lineTo(200, 105); |
| ctx.stroke(); |
| |
| // squished vertically |
| ctx.globalAlpha = 0.7; |
| ctx.imageSmoothingQuality = 'medium'; |
| ctx.drawImage(canvas._img, 150, 150, 150, 100); |
| ctx.rotate(-.2); |
| ctx.imageSmoothingEnabled = false; |
| ctx.drawImage(canvas._img, 100, 150, 400, 350, 10, 200, 150, 100); |
| |
| let idata = ctx.getImageData(80, 220, 40, 45); |
| ctx.putImageData(idata, 250, 10); |
| ctx.putImageData(idata, 200, 10, 20, 10, 20, 30); |
| ctx.resetTransform(); |
| ctx.strokeStyle = 'black'; |
| ctx.lineWidth = 1; |
| ctx.strokeRect(200, 10, 40, 45); |
| |
| idata = ctx.createImageData(10, 20); |
| ctx.putImageData(idata, 10, 10); |
| } |
| |
| document.getElementById('api1').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| }); |
| |
| } |
| |
| function CanvasAPI2(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api2_c'); |
| realCanvas.width = 300; |
| realCanvas.height = 300; |
| |
| // svg data for a clock |
| skcanvas._path = skcanvas.makePath2D('M11.99 2C6.47 2 2 6.48 2 12s4.47 10 9.99 10C17.52 22 22 17.52 22 12S17.52 2 11.99 2zM12 20c-4.42 0-8-3.58-8-8s3.58-8 8-8 8 3.58 8 8-3.58 8-8 8zm.5-13H11v6l5.25 3.15.75-1.23-4.5-2.67z'); |
| realCanvas._path = new Path2D('M11.99 2C6.47 2 2 6.48 2 12s4.47 10 9.99 10C17.52 22 22 17.52 22 12S17.52 2 11.99 2zM12 20c-4.42 0-8-3.58-8-8s3.58-8 8-8 8 3.58 8 8-3.58 8-8 8zm.5-13H11v6l5.25 3.15.75-1.23-4.5-2.67z'); |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.scale(1.5, 1.5); |
| ctx.moveTo(20, 5); |
| ctx.lineTo(30, 20); |
| ctx.lineTo(40, 10); |
| ctx.lineTo(50, 20); |
| ctx.lineTo(60, 0); |
| ctx.lineTo(20, 5); |
| |
| ctx.moveTo(20, 80); |
| ctx.bezierCurveTo(90, 10, 160, 150, 190, 10); |
| |
| ctx.moveTo(36, 148); |
| ctx.quadraticCurveTo(66, 188, 120, 136); |
| ctx.lineTo(36, 148); |
| |
| ctx.rect(5, 170, 20, 25); |
| |
| ctx.moveTo(150, 180); |
| ctx.arcTo(150, 100, 50, 200, 20); |
| ctx.lineTo(160, 160); |
| |
| ctx.moveTo(20, 120); |
| ctx.arc(20, 120, 18, 0, 1.75 * Math.PI); |
| ctx.lineTo(20, 120); |
| |
| ctx.moveTo(150, 5); |
| ctx.ellipse(130, 25, 30, 10, -1*Math.PI/8, Math.PI/6, 1.5*Math.PI); |
| |
| ctx.lineWidth = 4/3; |
| ctx.stroke(); |
| |
| // make a clock |
| ctx.stroke(canvas._path); |
| |
| // Test edgecases and draw direction |
| ctx.beginPath(); |
| ctx.arc(50, 100, 10, Math.PI, -Math.PI/2); |
| ctx.stroke(); |
| ctx.beginPath(); |
| ctx.arc(75, 100, 10, Math.PI, -Math.PI/2, true); |
| ctx.stroke(); |
| ctx.beginPath(); |
| ctx.arc(100, 100, 10, Math.PI, 100.1 * Math.PI, true); |
| ctx.stroke(); |
| ctx.beginPath(); |
| ctx.arc(125, 100, 10, Math.PI, 100.1 * Math.PI, false); |
| ctx.stroke(); |
| ctx.beginPath(); |
| ctx.ellipse(155, 100, 10, 15, Math.PI/8, 100.1 * Math.PI, Math.PI, true); |
| ctx.stroke(); |
| ctx.beginPath(); |
| ctx.ellipse(180, 100, 10, 15, Math.PI/8, Math.PI, 100.1 * Math.PI, true); |
| ctx.stroke(); |
| } |
| document.getElementById('api2').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function CanvasAPI3(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api3_c'); |
| realCanvas.width = 300; |
| realCanvas.height = 300; |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.rect(10, 10, 20, 20); |
| |
| ctx.scale(2.0, 4.0); |
| ctx.rect(30, 10, 20, 20); |
| ctx.resetTransform(); |
| |
| ctx.rotate(Math.PI / 3); |
| ctx.rect(50, 10, 20, 20); |
| ctx.resetTransform(); |
| |
| ctx.translate(30, -2); |
| ctx.rect(70, 10, 20, 20); |
| ctx.resetTransform(); |
| |
| ctx.translate(60, 0); |
| ctx.rotate(Math.PI / 6); |
| ctx.transform(1.5, 0, 0, 0.5, 0, 0); // effectively scale |
| ctx.rect(90, 10, 20, 20); |
| ctx.resetTransform(); |
| |
| ctx.save(); |
| ctx.setTransform(2, 0, -.5, 2.5, -40, 120); |
| ctx.rect(110, 10, 20, 20); |
| ctx.lineTo(110, 0); |
| ctx.restore(); |
| ctx.lineTo(220, 120); |
| |
| ctx.scale(3.0, 3.0); |
| ctx.font = '6pt Noto Mono'; |
| ctx.fillText('This text should be huge', 10, 80); |
| ctx.resetTransform(); |
| |
| ctx.strokeStyle = 'black'; |
| ctx.lineWidth = 2; |
| ctx.stroke(); |
| |
| ctx.beginPath(); |
| ctx.moveTo(250, 30); |
| ctx.lineTo(250, 80); |
| ctx.scale(3.0, 3.0); |
| ctx.lineTo(280/3, 90/3); |
| ctx.closePath(); |
| ctx.strokeStyle = 'black'; |
| ctx.lineWidth = 5; |
| ctx.stroke(); |
| |
| } |
| document.getElementById('api3').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function CanvasAPI4(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api4_c'); |
| realCanvas.width = 300; |
| realCanvas.height = 300; |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| |
| ctx.strokeStyle = '#000'; |
| ctx.fillStyle = '#CCC'; |
| ctx.shadowColor = 'rebeccapurple'; |
| ctx.shadowBlur = 1; |
| ctx.shadowOffsetX = 3; |
| ctx.shadowOffsetY = -8; |
| ctx.rect(10, 10, 30, 30); |
| |
| ctx.save(); |
| ctx.strokeStyle = '#C00'; |
| ctx.fillStyle = '#00C'; |
| ctx.shadowBlur = 0; |
| ctx.shadowColor = 'transparent'; |
| |
| ctx.stroke(); |
| |
| ctx.restore(); |
| ctx.fill(); |
| |
| ctx.beginPath(); |
| ctx.moveTo(36, 148); |
| ctx.quadraticCurveTo(66, 188, 120, 136); |
| ctx.closePath(); |
| ctx.stroke(); |
| |
| ctx.beginPath(); |
| ctx.shadowColor = '#993366AA'; |
| ctx.shadowOffsetX = 8; |
| ctx.shadowBlur = 5; |
| ctx.setTransform(2, 0, -.5, 2.5, -40, 120); |
| ctx.rect(110, 10, 20, 20); |
| ctx.lineTo(110, 0); |
| ctx.resetTransform(); |
| ctx.lineTo(220, 120); |
| ctx.stroke(); |
| |
| ctx.fillStyle = 'green'; |
| ctx.font = '16pt Noto Mono'; |
| ctx.fillText('This should be shadowed', 20, 80); |
| |
| ctx.beginPath(); |
| ctx.lineWidth = 6; |
| ctx.ellipse(10, 290, 30, 30, 0, 0, Math.PI * 2); |
| ctx.scale(2, 1); |
| ctx.moveTo(10, 290); |
| ctx.ellipse(10, 290, 30, 60, 0, 0, Math.PI * 2); |
| ctx.resetTransform(); |
| ctx.scale(3, 1); |
| ctx.moveTo(10, 290); |
| ctx.ellipse(10, 290, 30, 90, 0, 0, Math.PI * 2); |
| ctx.stroke(); |
| } |
| document.getElementById('api4').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function CanvasAPI5(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(600, 600); |
| let realCanvas = document.getElementById('api5_c'); |
| realCanvas.width = 600; |
| realCanvas.height = 600; |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.scale(1.1, 1.1); |
| ctx.translate(10, 10); |
| // Shouldn't impact the fillRect calls |
| ctx.setLineDash([5, 3]); |
| |
| ctx.fillStyle = 'rgba(200, 0, 100, 0.81)'; |
| ctx.fillRect(20, 30, 100, 100); |
| |
| ctx.globalAlpha = 0.81; |
| ctx.fillStyle = 'rgba(200, 0, 100, 1.0)'; |
| ctx.fillRect(120, 30, 100, 100); |
| // This shouldn't do anything |
| ctx.globalAlpha = 0.1; |
| |
| ctx.fillStyle = 'rgba(200, 0, 100, 0.9)'; |
| ctx.globalAlpha = 0.9; |
| // Intentional no-op to check ordering |
| ctx.clearRect(220, 30, 100, 100); |
| ctx.fillRect(220, 30, 100, 100); |
| |
| ctx.fillRect(320, 30, 100, 100); |
| ctx.clearRect(330, 40, 80, 80); |
| |
| ctx.strokeStyle = 'blue'; |
| ctx.lineWidth = 3; |
| ctx.setLineDash([5, 3]); |
| ctx.strokeRect(20, 150, 100, 100); |
| ctx.setLineDash([50, 30]); |
| ctx.strokeRect(125, 150, 100, 100); |
| ctx.lineDashOffset = 25; |
| ctx.strokeRect(230, 150, 100, 100); |
| ctx.setLineDash([2, 5, 9]); |
| ctx.strokeRect(335, 150, 100, 100); |
| |
| ctx.setLineDash([5, 2]); |
| ctx.moveTo(336, 400); |
| ctx.quadraticCurveTo(366, 488, 120, 450); |
| ctx.lineTo(300, 400); |
| ctx.stroke(); |
| |
| ctx.font = '36pt Noto Mono'; |
| ctx.strokeText('Dashed', 20, 350); |
| ctx.fillText('Not Dashed', 20, 400); |
| |
| } |
| document.getElementById('api5').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function CanvasAPI6(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(600, 600); |
| let realCanvas = document.getElementById('api6_c'); |
| realCanvas.width = 600; |
| realCanvas.height = 600; |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| |
| let rgradient = ctx.createRadialGradient(200, 300, 10, 100, 100, 300); |
| |
| // Add three color stops |
| rgradient.addColorStop(0, 'red'); |
| rgradient.addColorStop(0.7, 'white'); |
| rgradient.addColorStop(1, 'blue'); |
| |
| ctx.fillStyle = rgradient; |
| ctx.globalAlpha = 0.7; |
| ctx.fillRect(0, 0, 600, 600); |
| ctx.globalAlpha = 0.95; |
| |
| ctx.beginPath(); |
| ctx.arc(300, 100, 90, 0, Math.PI*1.66); |
| ctx.closePath(); |
| ctx.strokeStyle = 'yellow'; |
| ctx.lineWidth = 5; |
| ctx.stroke(); |
| ctx.save(); |
| ctx.clip(); |
| |
| let lgradient = ctx.createLinearGradient(200, 20, 420, 40); |
| |
| // Add three color stops |
| lgradient.addColorStop(0, 'green'); |
| lgradient.addColorStop(0.5, 'cyan'); |
| lgradient.addColorStop(1, 'orange'); |
| |
| ctx.fillStyle = lgradient; |
| |
| ctx.fillRect(200, 30, 200, 300); |
| |
| ctx.restore(); |
| ctx.fillRect(550, 550, 40, 40); |
| |
| } |
| document.getElementById('api6').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function CanvasAPI7(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api7_c'); |
| |
| let skPromise = fetch(cdn + 'test.png') |
| // if clients want to use a Blob, they are responsible |
| // for reading it themselves. |
| .then((response) => response.arrayBuffer()) |
| .then((buffer) => { |
| skcanvas._img = skcanvas.decodeImage(buffer); |
| }); |
| let realPromise = fetch(cdn + 'test.png') |
| .then((response) => response.blob()) |
| .then((blob) => createImageBitmap(blob)) |
| .then((bitmap) => { |
| realCanvas._img = bitmap; |
| }); |
| |
| |
| Promise.all([realPromise, skPromise]).then(() => { |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.fillStyle = '#EEE'; |
| ctx.fillRect(0, 0, 300, 300); |
| ctx.lineWidth = 20; |
| ctx.scale(0.1, 0.2); |
| |
| let pattern = ctx.createPattern(canvas._img, 'repeat'); |
| ctx.fillStyle = pattern; |
| ctx.fillRect(0, 0, 1500, 750); |
| |
| pattern = ctx.createPattern(canvas._img, 'repeat-x'); |
| ctx.fillStyle = pattern; |
| ctx.fillRect(1500, 0, 3000, 750); |
| |
| ctx.globalAlpha = 0.7; |
| pattern = ctx.createPattern(canvas._img, 'repeat-y'); |
| ctx.fillStyle = pattern; |
| ctx.fillRect(0, 750, 1500, 1500); |
| ctx.strokeRect(0, 750, 1500, 1500); |
| |
| pattern = ctx.createPattern(canvas._img, 'no-repeat'); |
| ctx.fillStyle = pattern; |
| pattern.setTransform({a: 1, b: -.1, c:.1, d: 0.5, e: 1800, f:800}); |
| ctx.fillRect(0, 0, 3000, 1500); |
| } |
| |
| document.getElementById('api7').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| }); |
| } |
| |
| function CanvasAPI8(CanvasKit) { |
| let skcanvas = CanvasKit.MakeCanvas(300, 300); |
| let realCanvas = document.getElementById('api8_c'); |
| |
| function drawPoint(ctx, x, y, color) { |
| ctx.fillStyle = color; |
| ctx.fillRect(x, y, 1, 1); |
| } |
| const IN = 'purple'; |
| const OUT = 'orange'; |
| const SCALE = 4; |
| |
| const pts = [[3, 3], [4, 4], [5, 5], [10, 10], [8, 10], [6, 10], |
| [6.5, 9], [15, 10], [17, 10], [17, 11], [24, 24], |
| [25, 25], [26, 26], [27, 27]]; |
| |
| const tests = [ |
| { |
| xOffset: 0, |
| yOffset: 0, |
| fillType: 'nonzero', |
| strokeWidth: 0, |
| testFn: (ctx, x, y) => ctx.isPointInPath(x * SCALE, y * SCALE, 'nonzero'), |
| }, |
| { |
| xOffset: 30, |
| yOffset: 0, |
| fillType: 'evenodd', |
| strokeWidth: 0, |
| testFn: (ctx, x, y) => ctx.isPointInPath(x * SCALE, y * SCALE, 'evenodd'), |
| }, |
| { |
| xOffset: 0, |
| yOffset: 30, |
| fillType: null, |
| strokeWidth: 1, |
| testFn: (ctx, x, y) => ctx.isPointInStroke(x * SCALE, y * SCALE), |
| }, |
| { |
| xOffset: 30, |
| yOffset: 30, |
| fillType: null, |
| strokeWidth: 2, |
| testFn: (ctx, x, y) => ctx.isPointInStroke(x * SCALE, y * SCALE), |
| }, |
| ]; |
| |
| for (let canvas of [skcanvas, realCanvas]) { |
| let ctx = canvas.getContext('2d'); |
| ctx.font = '11px Noto Mono'; |
| // Draw some visual aids |
| ctx.fillText('path-nonzero', 30, 15); |
| ctx.fillText('path-evenodd', 150, 15); |
| ctx.fillText('stroke-1px-wide', 30, 130); |
| ctx.fillText('stroke-2px-wide', 150, 130); |
| ctx.fillText('purple is IN, orange is OUT', 10, 280); |
| |
| // Scale up to make single pixels easier to see |
| ctx.scale(SCALE, SCALE); |
| for (let test of tests) { |
| ctx.beginPath(); |
| let xOffset = test.xOffset; |
| let yOffset = test.yOffset; |
| |
| ctx.fillStyle = '#AAA'; |
| ctx.lineWidth = test.strokeWidth; |
| ctx.rect(5+xOffset, 5+yOffset, 20, 20); |
| ctx.arc(15+xOffset, 15+yOffset, 8, 0, Math.PI*2, false); |
| if (test.fillType) { |
| ctx.fill(test.fillType); |
| } else { |
| ctx.stroke(); |
| } |
| |
| for (let pt of pts) { |
| let [x, y] = pt; |
| x += xOffset; |
| y += yOffset; |
| // naively apply transform when querying because the points queried |
| // ignore the CTM. |
| if (test.testFn(ctx, x, y)) { |
| drawPoint(ctx, x, y, IN); |
| } else { |
| drawPoint(ctx, x, y, OUT); |
| } |
| } |
| } |
| } |
| |
| document.getElementById('api8').src = skcanvas.toDataURL(); |
| skcanvas.dispose(); |
| } |
| |
| function VertexAPI1(CanvasKit) { |
| const surface = CanvasKit.MakeCanvasSurface('vertex1'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const canvas = surface.getCanvas(); |
| let paint = new CanvasKit.Paint(); |
| |
| // See https://fiddle.skia.org/c/f48b22eaad1bb7adcc3faaa321754af6 |
| // for original c++ version. |
| let points = [0, 0, 250, 0, 100, 100, 0, 250]; |
| let colors = [CanvasKit.RED, CanvasKit.BLUE, |
| CanvasKit.YELLOW, CanvasKit.CYAN]; |
| let vertices = CanvasKit.MakeVertices(CanvasKit.VertexMode.TriangleFan, |
| points, null, colors, |
| false /*isVolatile*/); |
| |
| canvas.drawVertices(vertices, CanvasKit.BlendMode.Src, paint); |
| |
| vertices.delete(); |
| |
| // See https://fiddle.skia.org/c/e8bdae9bea3227758989028424fcac3d |
| // for original c++ version. |
| points = [300, 300, 50, 300, 200, 200, 300, 50 ]; |
| let texs = [ 0, 0, 0, 250, 250, 250, 250, 0 ]; |
| vertices = CanvasKit.MakeVertices(CanvasKit.VertexMode.TriangleFan, |
| points, texs, colors); |
| |
| let shader = CanvasKit.Shader.MakeLinearGradient([0, 0], [250, 0], |
| colors, null, CanvasKit.TileMode.Clamp); |
| paint.setShader(shader); |
| |
| canvas.drawVertices(vertices, CanvasKit.BlendMode.Darken, paint); |
| surface.flush(); |
| |
| shader.delete(); |
| paint.delete(); |
| surface.delete(); |
| } |
| |
| function GradiantAPI1(CanvasKit) { |
| const surface = CanvasKit.MakeSWCanvasSurface('gradient1'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const canvas = surface.getCanvas(); |
| let paint = new CanvasKit.Paint(); |
| |
| // See https://fiddle.skia.org/c/f48b22eaad1bb7adcc3faaa321754af6 |
| // for original c++ version. |
| let colors = [CanvasKit.BLUE, CanvasKit.YELLOW, CanvasKit.RED]; |
| let pos = [0, .7, 1.0]; |
| let transform = [2, 0, 0, |
| 0, 2, 0, |
| 0, 0, 1]; |
| let shader = CanvasKit.Shader.MakeRadialGradient([150, 150], 130, colors, |
| pos, CanvasKit.TileMode.Mirror, transform); |
| |
| paint.setShader(shader); |
| const textFont = new CanvasKit.Font(null, 75); |
| const textBlob = CanvasKit.TextBlob.MakeFromText('Radial', textFont); |
| |
| canvas.drawTextBlob(textBlob, 10, 200, paint); |
| paint.delete(); |
| textFont.delete(); |
| textBlob.delete(); |
| surface.flush(); |
| } |
| |
| function TextOnPathAPI1(CanvasKit) { |
| const surface = CanvasKit.MakeSWCanvasSurface('textonpath'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const canvas = surface.getCanvas(); |
| const paint = new CanvasKit.Paint(); |
| paint.setStyle(CanvasKit.PaintStyle.Stroke); |
| paint.setAntiAlias(true); |
| |
| const font = new CanvasKit.Font(null, 24); |
| const fontPaint = new CanvasKit.Paint(); |
| fontPaint.setStyle(CanvasKit.PaintStyle.Fill); |
| fontPaint.setAntiAlias(true); |
| |
| const arc = new CanvasKit.Path(); |
| arc.arcToOval(CanvasKit.LTRBRect(20, 40, 280, 300), -160, 140, true); |
| arc.lineTo(210, 140); |
| arc.arcToOval(CanvasKit.LTRBRect(20, 0, 280, 260), 160, -140, true); |
| |
| const str = 'This téxt should follow the curve across contours...'; |
| const textBlob = CanvasKit.TextBlob.MakeOnPath(str, arc, font); |
| |
| canvas.drawPath(arc, paint); |
| canvas.drawTextBlob(textBlob, 0, 0, fontPaint); |
| |
| surface.flush(); |
| |
| textBlob.delete(); |
| arc.delete(); |
| paint.delete(); |
| font.delete(); |
| fontPaint.delete(); |
| } |
| |
| function DrawGlyphsAPI1(CanvasKit) { |
| const surface = CanvasKit.MakeSWCanvasSurface('drawGlyphs'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const canvas = surface.getCanvas(); |
| const paint = new CanvasKit.Paint(); |
| const font = new CanvasKit.Font(null, 16); |
| paint.setAntiAlias(true); |
| |
| let glyphs = []; |
| let positions = []; |
| for (let i = 0; i < 256; ++i) { |
| glyphs.push(i); |
| positions.push((i % 16) * 16); |
| positions.push(Math.round(i/16) * 16); |
| } |
| canvas.drawGlyphs(glyphs, positions, 16, 20, font, paint); |
| |
| surface.flush(); |
| |
| paint.delete(); |
| font.delete(); |
| } |
| |
| function SurfaceAPI1(CanvasKit) { |
| const surface = CanvasKit.MakeCanvasSurface('surfaces'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const grContext = surface.grContext; |
| |
| // create a subsurface as a temporary workspace. |
| const subSurface = surface.makeSurface({ |
| width: 50, |
| height: 50, |
| alphaType: CanvasKit.AlphaType.Premul, |
| colorType: CanvasKit.ColorType.RGBA_8888, |
| colorSpace: CanvasKit.ColorSpace.SRGB, |
| }); |
| |
| if (!subSurface) { |
| console.error('Could not make subsurface'); |
| return; |
| } |
| |
| // draw a small "scene" |
| const paint = new CanvasKit.Paint(); |
| paint.setColor(CanvasKit.Color(139, 228, 135, 0.95)); // greenish |
| paint.setStyle(CanvasKit.PaintStyle.Fill); |
| paint.setAntiAlias(true); |
| |
| const subCanvas = subSurface.getCanvas(); |
| subCanvas.clear(CanvasKit.BLACK); |
| subCanvas.drawRect(CanvasKit.LTRBRect(5, 15, 45, 40), paint); |
| |
| paint.setColor(CanvasKit.Color(214, 93, 244)); // purplish |
| for (let i = 0; i < 10; i++) { |
| const x = Math.random() * 50; |
| const y = Math.random() * 50; |
| |
| subCanvas.drawOval(CanvasKit.XYWHRect(x, y, 6, 6), paint); |
| } |
| |
| // Snap it off as an Image - this image will be in the form the |
| // parent surface prefers (e.g. Texture for GPU / Raster for CPU). |
| const img = subSurface.makeImageSnapshot(); |
| |
| // clean up the temporary surface (which also cleans up subCanvas) |
| subSurface.delete(); |
| paint.delete(); |
| |
| // Make it repeat a bunch with a shader |
| const pattern = img.makeShaderCubic(CanvasKit.TileMode.Repeat, CanvasKit.TileMode.Mirror, |
| 1/3, 1/3); |
| const patternPaint = new CanvasKit.Paint(); |
| patternPaint.setShader(pattern); |
| |
| let i = 0; |
| |
| function drawFrame(canvas) { |
| i++; |
| canvas.clear(CanvasKit.WHITE); |
| |
| canvas.drawOval(CanvasKit.LTRBRect(i % 60, i % 60, 300 - (i% 60), 300 - (i % 60)), patternPaint); |
| surface.requestAnimationFrame(drawFrame); |
| // if (grContext) { |
| // console.log(grContext.getResourceCacheUsageBytes() + ' bytes used in the GPU'); |
| // } |
| } |
| surface.requestAnimationFrame(drawFrame); |
| } |
| |
| function AtlasAPI1(CanvasKit, imgData) { |
| if (!CanvasKit || !imgData) { |
| return; |
| } |
| const surface = CanvasKit.MakeCanvasSurface('atlas'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const img = CanvasKit.MakeImageFromEncoded(imgData); |
| |
| const paint = new CanvasKit.Paint(); |
| paint.setColor(CanvasKit.Color(0, 0, 0, 0.8)); |
| |
| // Allocate space for 2 rectangles. |
| const srcs = CanvasKit.Malloc(Float32Array, 8); |
| srcs.toTypedArray().set([ |
| 0, 0, 250, 250, // LTRB |
| 250, 0, 500, 250 |
| ]); |
| |
| // Allocate space for 2 RSXForms |
| const dsts = CanvasKit.Malloc(Float32Array, 8); |
| dsts.toTypedArray().set([ |
| .5, 0, 0, 0, // scos, ssin, tx, ty |
| 0, .8, 200, 100 |
| ]); |
| |
| // Allocate space for 4 colors. |
| const colors = new CanvasKit.Malloc(Uint32Array, 2); |
| colors.toTypedArray().set([ |
| CanvasKit.ColorAsInt( 85, 170, 10, 128), // light green |
| CanvasKit.ColorAsInt( 51, 51, 191, 128), // light blue |
| ]); |
| |
| let i = 0; |
| |
| function drawFrame(canvas) { |
| canvas.clear(CanvasKit.WHITE); |
| i++; |
| let scale = 0.5 + Math.sin(i/40)/4; |
| |
| // update the coordinates of existing sprites - note that this |
| // does not require a full re-copy of the full array; they are |
| // updated in-place. |
| dsts.toTypedArray().set([0.5, 0, (2*i)%200, (5*Math.round(i/200)) % 200], 0); |
| dsts.toTypedArray().set([scale*Math.sin(i/20), scale*Math.cos(i/20), 200, 100], 4); |
| |
| canvas.drawAtlas(img, srcs, dsts, paint, CanvasKit.BlendMode.Plus, colors, |
| {filter: CanvasKit.FilterMode.Nearest}); |
| surface.requestAnimationFrame(drawFrame); |
| } |
| surface.requestAnimationFrame(drawFrame); |
| |
| } |
| |
| async function DecodeAPI(CanvasKit, imgData) { |
| if (!CanvasKit || !imgData) { |
| return; |
| } |
| const surface = CanvasKit.MakeCanvasSurface('decode'); |
| if (!surface) { |
| console.error('Could not make surface'); |
| return; |
| } |
| const blob = new Blob([ imgData ]); |
| // ImageBitmap is not supported in Safari |
| const imageBitmap = await createImageBitmap(blob); |
| const img = await CanvasKit.MakeImageFromCanvasImageSource(imageBitmap); |
| |
| surface.drawOnce((canvas) => { |
| canvas.drawImage(img, 0, 0, null); |
| }); |
| } |
| </script> |
