xref: /aosp_15_r20/external/skia/demos.skia.org/demos/spreadsheet/index.html (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
1*c8dee2aaSAndroid Build Coastguard Worker<!DOCTYPE html>
2*c8dee2aaSAndroid Build Coastguard Worker<title>Spreadsheet Demo</title>
3*c8dee2aaSAndroid Build Coastguard Worker<meta charset="utf-8" />
4*c8dee2aaSAndroid Build Coastguard Worker<meta http-equiv="X-UA-Compatible" content="IE=edge">
5*c8dee2aaSAndroid Build Coastguard Worker<meta name="viewport" content="width=device-width, initial-scale=1.0">
6*c8dee2aaSAndroid Build Coastguard Worker<script type="text/javascript" src="https://unpkg.com/[email protected]/bin/full/canvaskit.js"></script>
7*c8dee2aaSAndroid Build Coastguard Worker
8*c8dee2aaSAndroid Build Coastguard Worker<style>
9*c8dee2aaSAndroid Build Coastguard Worker  body {
10*c8dee2aaSAndroid Build Coastguard Worker      background-color: black;
11*c8dee2aaSAndroid Build Coastguard Worker  }
12*c8dee2aaSAndroid Build Coastguard Worker  h1 {
13*c8dee2aaSAndroid Build Coastguard Worker      color: white;
14*c8dee2aaSAndroid Build Coastguard Worker  }
15*c8dee2aaSAndroid Build Coastguard Worker  .hidden {
16*c8dee2aaSAndroid Build Coastguard Worker      display: none;
17*c8dee2aaSAndroid Build Coastguard Worker  }
18*c8dee2aaSAndroid Build Coastguard Worker</style>
19*c8dee2aaSAndroid Build Coastguard Worker
20*c8dee2aaSAndroid Build Coastguard Worker<body>
21*c8dee2aaSAndroid Build Coastguard Worker  <h1>Large canvas with many numbers, like a spreadsheet</h1>
22*c8dee2aaSAndroid Build Coastguard Worker  <select id="numbers_impl">
23*c8dee2aaSAndroid Build Coastguard Worker    <option value="fillText">&lt;canvas&gt; fillText</option>
24*c8dee2aaSAndroid Build Coastguard Worker    <option value="drawGlyphs">CK drawGlyphs (tuned)</option>
25*c8dee2aaSAndroid Build Coastguard Worker    <option value="drawText">CK drawText (naive)</option>
26*c8dee2aaSAndroid Build Coastguard Worker  </select>
27*c8dee2aaSAndroid Build Coastguard Worker
28*c8dee2aaSAndroid Build Coastguard Worker  <canvas id=ck_canvas width=3840 height=2160 class="hidden"></canvas>
29*c8dee2aaSAndroid Build Coastguard Worker  <canvas id=canvas_2d width=3840 height=2160></canvas>
30*c8dee2aaSAndroid Build Coastguard Worker</body>
31*c8dee2aaSAndroid Build Coastguard Worker
32*c8dee2aaSAndroid Build Coastguard Worker<script type="text/javascript" charset="utf-8">
33*c8dee2aaSAndroid Build Coastguard Worker  const ckLoaded = CanvasKitInit({ locateFile: (file) => 'https://unpkg.com/[email protected]/bin/full/' + file });
34*c8dee2aaSAndroid Build Coastguard Worker
35*c8dee2aaSAndroid Build Coastguard Worker  // This is the dimensions of a 4k screen.
36*c8dee2aaSAndroid Build Coastguard Worker  const WIDTH = 3840, HEIGHT = 2160;
37*c8dee2aaSAndroid Build Coastguard Worker  const ROWS = 144;
38*c8dee2aaSAndroid Build Coastguard Worker  const ROW_HEIGHT = 15;
39*c8dee2aaSAndroid Build Coastguard Worker  const COLS = 77;
40*c8dee2aaSAndroid Build Coastguard Worker  const COL_WIDTH = 50;
41*c8dee2aaSAndroid Build Coastguard Worker  const canvas2DEle = document.getElementById('canvas_2d');
42*c8dee2aaSAndroid Build Coastguard Worker  const ckEle = document.getElementById('ck_canvas');
43*c8dee2aaSAndroid Build Coastguard Worker
44*c8dee2aaSAndroid Build Coastguard Worker  ckLoaded.then((CanvasKit) => {
45*c8dee2aaSAndroid Build Coastguard Worker    const canvas2dCtx = canvas2DEle.getContext('2d');
46*c8dee2aaSAndroid Build Coastguard Worker    const surface = CanvasKit.MakeCanvasSurface('ck_canvas');
47*c8dee2aaSAndroid Build Coastguard Worker    if (!surface) {
48*c8dee2aaSAndroid Build Coastguard Worker      throw 'Could not make surface';
49*c8dee2aaSAndroid Build Coastguard Worker    }
50*c8dee2aaSAndroid Build Coastguard Worker
51*c8dee2aaSAndroid Build Coastguard Worker    const colorPaints = {
52*c8dee2aaSAndroid Build Coastguard Worker      "grey": CanvasKit.Color(76, 76, 76),
53*c8dee2aaSAndroid Build Coastguard Worker      "black": CanvasKit.BLACK,
54*c8dee2aaSAndroid Build Coastguard Worker      "white": CanvasKit.WHITE,
55*c8dee2aaSAndroid Build Coastguard Worker      "springGreen": CanvasKit.Color(0, 255, 127),
56*c8dee2aaSAndroid Build Coastguard Worker      "tomato": CanvasKit.Color(255, 99, 71),
57*c8dee2aaSAndroid Build Coastguard Worker    };
58*c8dee2aaSAndroid Build Coastguard Worker    for (const name in colorPaints) {
59*c8dee2aaSAndroid Build Coastguard Worker      const color = colorPaints[name];
60*c8dee2aaSAndroid Build Coastguard Worker      const paint = new CanvasKit.Paint();
61*c8dee2aaSAndroid Build Coastguard Worker      paint.setColor(color);
62*c8dee2aaSAndroid Build Coastguard Worker      colorPaints[name] = paint;
63*c8dee2aaSAndroid Build Coastguard Worker    }
64*c8dee2aaSAndroid Build Coastguard Worker
65*c8dee2aaSAndroid Build Coastguard Worker    const data = [];
66*c8dee2aaSAndroid Build Coastguard Worker    for (let row = 0; row < ROWS; row++) {
67*c8dee2aaSAndroid Build Coastguard Worker      data[row] = [];
68*c8dee2aaSAndroid Build Coastguard Worker      for (let col = 0; col < COLS; col++) {
69*c8dee2aaSAndroid Build Coastguard Worker        data[row][col] = Math.random() * Math.PI;
70*c8dee2aaSAndroid Build Coastguard Worker      }
71*c8dee2aaSAndroid Build Coastguard Worker    }
72*c8dee2aaSAndroid Build Coastguard Worker
73*c8dee2aaSAndroid Build Coastguard Worker    // Maybe use https://storage.googleapis.com/skia-cdn/google-web-fonts/NotoSans-Regular.ttf
74*c8dee2aaSAndroid Build Coastguard Worker    const textFont = new CanvasKit.Font(null, 12);
75*c8dee2aaSAndroid Build Coastguard Worker
76*c8dee2aaSAndroid Build Coastguard Worker    const choice = document.getElementById("numbers_impl");
77*c8dee2aaSAndroid Build Coastguard Worker
78*c8dee2aaSAndroid Build Coastguard Worker    let frames = [];
79*c8dee2aaSAndroid Build Coastguard Worker    const framesToMeasure = 10;
80*c8dee2aaSAndroid Build Coastguard Worker    choice.addEventListener("change", () => {
81*c8dee2aaSAndroid Build Coastguard Worker      frames = [];
82*c8dee2aaSAndroid Build Coastguard Worker      if (choice.selectedIndex === 0) {
83*c8dee2aaSAndroid Build Coastguard Worker        canvas2DEle.classList.remove('hidden');
84*c8dee2aaSAndroid Build Coastguard Worker        ckEle.classList.add('hidden');
85*c8dee2aaSAndroid Build Coastguard Worker      } else {
86*c8dee2aaSAndroid Build Coastguard Worker        canvas2DEle.classList.add('hidden');
87*c8dee2aaSAndroid Build Coastguard Worker        ckEle.classList.remove('hidden');
88*c8dee2aaSAndroid Build Coastguard Worker      }
89*c8dee2aaSAndroid Build Coastguard Worker    })
90*c8dee2aaSAndroid Build Coastguard Worker    function drawFrame(canvas) {
91*c8dee2aaSAndroid Build Coastguard Worker      if (frames && frames.length === framesToMeasure) {
92*c8dee2aaSAndroid Build Coastguard Worker        // It is important to measure frame to frame time to account for the time spent by the
93*c8dee2aaSAndroid Build Coastguard Worker        // GPU after our flush calls.
94*c8dee2aaSAndroid Build Coastguard Worker        const deltas = [];
95*c8dee2aaSAndroid Build Coastguard Worker        for (let i = 0; i< frames.length-1;i++) {
96*c8dee2aaSAndroid Build Coastguard Worker          deltas.push(frames[i+1] - frames[i]);
97*c8dee2aaSAndroid Build Coastguard Worker        }
98*c8dee2aaSAndroid Build Coastguard Worker        console.log(`First ${framesToMeasure} frames`, deltas);
99*c8dee2aaSAndroid Build Coastguard Worker        console.log((frames[framesToMeasure-1] - frames[0]) / framesToMeasure);
100*c8dee2aaSAndroid Build Coastguard Worker        frames = null;
101*c8dee2aaSAndroid Build Coastguard Worker      } else if (frames) {
102*c8dee2aaSAndroid Build Coastguard Worker        frames.push(performance.now());
103*c8dee2aaSAndroid Build Coastguard Worker      }
104*c8dee2aaSAndroid Build Coastguard Worker
105*c8dee2aaSAndroid Build Coastguard Worker      if (choice.selectedIndex === 2) {
106*c8dee2aaSAndroid Build Coastguard Worker        canvas.clear(CanvasKit.BLACK);
107*c8dee2aaSAndroid Build Coastguard Worker        drawTextImpl(canvas);
108*c8dee2aaSAndroid Build Coastguard Worker      } else if (choice.selectedIndex === 1) {
109*c8dee2aaSAndroid Build Coastguard Worker        canvas.clear(CanvasKit.BLACK);
110*c8dee2aaSAndroid Build Coastguard Worker        drawGlyphsImpl(canvas);
111*c8dee2aaSAndroid Build Coastguard Worker      } else {
112*c8dee2aaSAndroid Build Coastguard Worker        fillTextImpl(canvas2dCtx);
113*c8dee2aaSAndroid Build Coastguard Worker      }
114*c8dee2aaSAndroid Build Coastguard Worker
115*c8dee2aaSAndroid Build Coastguard Worker      surface.requestAnimationFrame(drawFrame)
116*c8dee2aaSAndroid Build Coastguard Worker    }
117*c8dee2aaSAndroid Build Coastguard Worker
118*c8dee2aaSAndroid Build Coastguard Worker    function drawTextImpl(canvas) {
119*c8dee2aaSAndroid Build Coastguard Worker      const timer = performance.now() / 10000;
120*c8dee2aaSAndroid Build Coastguard Worker      for (let row = 0; row < ROWS; row++) {
121*c8dee2aaSAndroid Build Coastguard Worker        if (row % 2) {
122*c8dee2aaSAndroid Build Coastguard Worker          canvas.drawRect(CanvasKit.XYWHRect(0, row * ROW_HEIGHT + 2, WIDTH, ROW_HEIGHT), colorPaints["grey"]);
123*c8dee2aaSAndroid Build Coastguard Worker        }
124*c8dee2aaSAndroid Build Coastguard Worker        for (let col = 0; col < COLS; col++) {
125*c8dee2aaSAndroid Build Coastguard Worker          let n = Math.abs(Math.sin(timer + data[row][col]));
126*c8dee2aaSAndroid Build Coastguard Worker          let useWhiteFont = true;
127*c8dee2aaSAndroid Build Coastguard Worker          if (n < 0.05) {
128*c8dee2aaSAndroid Build Coastguard Worker            canvas.drawRect(CanvasKit.XYWHRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT), colorPaints["tomato"]);
129*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
130*c8dee2aaSAndroid Build Coastguard Worker          } else if (n > 0.95) {
131*c8dee2aaSAndroid Build Coastguard Worker            canvas.drawRect(CanvasKit.XYWHRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT), colorPaints["springGreen"]);
132*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
133*c8dee2aaSAndroid Build Coastguard Worker          }
134*c8dee2aaSAndroid Build Coastguard Worker          const str = n.toFixed(4);
135*c8dee2aaSAndroid Build Coastguard Worker          canvas.drawText(str, col * COL_WIDTH, row * ROW_HEIGHT,
136*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont ? colorPaints["white"] : colorPaints["black"], textFont);
137*c8dee2aaSAndroid Build Coastguard Worker        }
138*c8dee2aaSAndroid Build Coastguard Worker      }
139*c8dee2aaSAndroid Build Coastguard Worker    }
140*c8dee2aaSAndroid Build Coastguard Worker
141*c8dee2aaSAndroid Build Coastguard Worker    //====================================================================================
142*c8dee2aaSAndroid Build Coastguard Worker    const alphabet = "0.123456789 ";
143*c8dee2aaSAndroid Build Coastguard Worker    const glyphIDs = textFont.getGlyphIDs(alphabet);
144*c8dee2aaSAndroid Build Coastguard Worker    // These are all 7 with current font and size
145*c8dee2aaSAndroid Build Coastguard Worker    const advances = textFont.getGlyphWidths(glyphIDs);
146*c8dee2aaSAndroid Build Coastguard Worker
147*c8dee2aaSAndroid Build Coastguard Worker
148*c8dee2aaSAndroid Build Coastguard Worker    const charsPerDataPoint = 6; // leading 0, period, 4 decimal places
149*c8dee2aaSAndroid Build Coastguard Worker    const glyphIDsMObj = CanvasKit.MallocGlyphIDs(ROWS * COLS * charsPerDataPoint);
150*c8dee2aaSAndroid Build Coastguard Worker    let wasmGlyphIDArr = glyphIDsMObj.toTypedArray();
151*c8dee2aaSAndroid Build Coastguard Worker    const glyphLocationsMObj = CanvasKit.Malloc(Float32Array, glyphIDsMObj.length * 2);
152*c8dee2aaSAndroid Build Coastguard Worker    let wasmGlyphLocations = glyphLocationsMObj.toTypedArray();
153*c8dee2aaSAndroid Build Coastguard Worker
154*c8dee2aaSAndroid Build Coastguard Worker    function dataToGlyphs(n, outputBuffer, offset) {
155*c8dee2aaSAndroid Build Coastguard Worker      const s = n.toFixed(4);
156*c8dee2aaSAndroid Build Coastguard Worker      outputBuffer[offset] = glyphIDs[0]; // Always a leading 0
157*c8dee2aaSAndroid Build Coastguard Worker      outputBuffer[offset+1] = glyphIDs[1]; // Always a decimal place
158*c8dee2aaSAndroid Build Coastguard Worker      for (let i = 2; i< charsPerDataPoint; i++) {
159*c8dee2aaSAndroid Build Coastguard Worker        outputBuffer[offset+i] = glyphIDs[alphabet.indexOf(s[i])];
160*c8dee2aaSAndroid Build Coastguard Worker      }
161*c8dee2aaSAndroid Build Coastguard Worker    }
162*c8dee2aaSAndroid Build Coastguard Worker    const spaceIndex = alphabet.length - 1;
163*c8dee2aaSAndroid Build Coastguard Worker    function blankOut(outputBuffer, offset) {
164*c8dee2aaSAndroid Build Coastguard Worker      for (let i = 0; i< charsPerDataPoint; i++) {
165*c8dee2aaSAndroid Build Coastguard Worker        outputBuffer[offset+i] = glyphIDs[spaceIndex];
166*c8dee2aaSAndroid Build Coastguard Worker      }
167*c8dee2aaSAndroid Build Coastguard Worker    }
168*c8dee2aaSAndroid Build Coastguard Worker
169*c8dee2aaSAndroid Build Coastguard Worker    for (let row = 0; row < ROWS; row++) {
170*c8dee2aaSAndroid Build Coastguard Worker      for (let col = 0; col < COLS; col++) {
171*c8dee2aaSAndroid Build Coastguard Worker        for (let i = 0; i < charsPerDataPoint; i++) {
172*c8dee2aaSAndroid Build Coastguard Worker          const offset = (col + row * COLS) * charsPerDataPoint * 2;
173*c8dee2aaSAndroid Build Coastguard Worker          wasmGlyphLocations[offset + i * 2] = col * COL_WIDTH + i * advances[0];
174*c8dee2aaSAndroid Build Coastguard Worker          wasmGlyphLocations[offset + i * 2 + 1] = row * ROW_HEIGHT;
175*c8dee2aaSAndroid Build Coastguard Worker        }
176*c8dee2aaSAndroid Build Coastguard Worker      }
177*c8dee2aaSAndroid Build Coastguard Worker    }
178*c8dee2aaSAndroid Build Coastguard Worker
179*c8dee2aaSAndroid Build Coastguard Worker    const greyGlyphIDsMObj = CanvasKit.MallocGlyphIDs(charsPerDataPoint);
180*c8dee2aaSAndroid Build Coastguard Worker
181*c8dee2aaSAndroid Build Coastguard Worker    function drawGlyphsImpl(canvas) {
182*c8dee2aaSAndroid Build Coastguard Worker      wasmGlyphIDArr = glyphIDsMObj.toTypedArray();
183*c8dee2aaSAndroid Build Coastguard Worker      let wasmGreyGlyphIDsArr = greyGlyphIDsMObj.toTypedArray();
184*c8dee2aaSAndroid Build Coastguard Worker
185*c8dee2aaSAndroid Build Coastguard Worker      const timer = performance.now() / 10000;
186*c8dee2aaSAndroid Build Coastguard Worker      for (let row = 0; row < ROWS; row++) {
187*c8dee2aaSAndroid Build Coastguard Worker        if (row % 2) {
188*c8dee2aaSAndroid Build Coastguard Worker          canvas.drawRect(CanvasKit.XYWHRect(0, row * ROW_HEIGHT + 2, WIDTH, ROW_HEIGHT), colorPaints["grey"]);
189*c8dee2aaSAndroid Build Coastguard Worker        }
190*c8dee2aaSAndroid Build Coastguard Worker        for (let col = 0; col < COLS; col++) {
191*c8dee2aaSAndroid Build Coastguard Worker          const n = Math.abs(Math.sin(timer + data[row][col]));
192*c8dee2aaSAndroid Build Coastguard Worker          let useWhiteFont = true;
193*c8dee2aaSAndroid Build Coastguard Worker          if (n < 0.05) {
194*c8dee2aaSAndroid Build Coastguard Worker            canvas.drawRect(CanvasKit.XYWHRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT), colorPaints["tomato"]);
195*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
196*c8dee2aaSAndroid Build Coastguard Worker          } else if (n > 0.95) {
197*c8dee2aaSAndroid Build Coastguard Worker            canvas.drawRect(CanvasKit.XYWHRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT), colorPaints["springGreen"]);
198*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
199*c8dee2aaSAndroid Build Coastguard Worker          }
200*c8dee2aaSAndroid Build Coastguard Worker
201*c8dee2aaSAndroid Build Coastguard Worker          const offset = (col + row * COLS) * charsPerDataPoint;
202*c8dee2aaSAndroid Build Coastguard Worker          if (useWhiteFont) {
203*c8dee2aaSAndroid Build Coastguard Worker            dataToGlyphs(n, wasmGlyphIDArr, offset);
204*c8dee2aaSAndroid Build Coastguard Worker          } else {
205*c8dee2aaSAndroid Build Coastguard Worker            blankOut(wasmGlyphIDArr, offset);
206*c8dee2aaSAndroid Build Coastguard Worker            dataToGlyphs(n, wasmGreyGlyphIDsArr, 0);
207*c8dee2aaSAndroid Build Coastguard Worker            canvas.drawGlyphs(wasmGreyGlyphIDsArr,
208*c8dee2aaSAndroid Build Coastguard Worker              glyphLocationsMObj.subarray(offset*2, (offset + charsPerDataPoint) * 2),
209*c8dee2aaSAndroid Build Coastguard Worker              0, 0, textFont, colorPaints["grey"]
210*c8dee2aaSAndroid Build Coastguard Worker            );
211*c8dee2aaSAndroid Build Coastguard Worker          }
212*c8dee2aaSAndroid Build Coastguard Worker        }
213*c8dee2aaSAndroid Build Coastguard Worker      }
214*c8dee2aaSAndroid Build Coastguard Worker      canvas.drawGlyphs(wasmGlyphIDArr, glyphLocationsMObj, 0, 0, textFont, colorPaints["white"]);
215*c8dee2aaSAndroid Build Coastguard Worker    }
216*c8dee2aaSAndroid Build Coastguard Worker
217*c8dee2aaSAndroid Build Coastguard Worker    function fillTextImpl(ctx) {
218*c8dee2aaSAndroid Build Coastguard Worker      ctx.font = '12px monospace';
219*c8dee2aaSAndroid Build Coastguard Worker      ctx.fillStyle = 'black';
220*c8dee2aaSAndroid Build Coastguard Worker      ctx.fillRect(0, 0, WIDTH, HEIGHT);
221*c8dee2aaSAndroid Build Coastguard Worker      const timer = performance.now() / 10000;
222*c8dee2aaSAndroid Build Coastguard Worker      for (let row = 0; row < ROWS; row++) {
223*c8dee2aaSAndroid Build Coastguard Worker        if (row % 2) {
224*c8dee2aaSAndroid Build Coastguard Worker          ctx.fillStyle = 'rgb(76,76,76)';
225*c8dee2aaSAndroid Build Coastguard Worker          ctx.fillRect(0, row * ROW_HEIGHT + 2, WIDTH, ROW_HEIGHT);
226*c8dee2aaSAndroid Build Coastguard Worker        }
227*c8dee2aaSAndroid Build Coastguard Worker        for (let col = 0; col < COLS; col++) {
228*c8dee2aaSAndroid Build Coastguard Worker          let n = Math.abs(Math.sin(timer + data[row][col]));
229*c8dee2aaSAndroid Build Coastguard Worker          let useWhiteFont = true;
230*c8dee2aaSAndroid Build Coastguard Worker          if (n < 0.05) {
231*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillStyle = 'rgb(255, 99, 71)';
232*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT);
233*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
234*c8dee2aaSAndroid Build Coastguard Worker          } else if (n > 0.95) {
235*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillStyle = 'rgb(0, 255, 127)';
236*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillRect(col * COL_WIDTH - 2, (row - 1) * ROW_HEIGHT + 2, COL_WIDTH, ROW_HEIGHT);
237*c8dee2aaSAndroid Build Coastguard Worker            useWhiteFont = false;
238*c8dee2aaSAndroid Build Coastguard Worker          }
239*c8dee2aaSAndroid Build Coastguard Worker          const str = n.toFixed(4);
240*c8dee2aaSAndroid Build Coastguard Worker          if (useWhiteFont) {
241*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillStyle = 'white';
242*c8dee2aaSAndroid Build Coastguard Worker          } else {
243*c8dee2aaSAndroid Build Coastguard Worker            ctx.fillStyle = 'black';
244*c8dee2aaSAndroid Build Coastguard Worker          }
245*c8dee2aaSAndroid Build Coastguard Worker          ctx.fillText(str, col * COL_WIDTH, row * ROW_HEIGHT);
246*c8dee2aaSAndroid Build Coastguard Worker        }
247*c8dee2aaSAndroid Build Coastguard Worker      }
248*c8dee2aaSAndroid Build Coastguard Worker    }
249*c8dee2aaSAndroid Build Coastguard Worker
250*c8dee2aaSAndroid Build Coastguard Worker    surface.requestAnimationFrame(drawFrame);
251*c8dee2aaSAndroid Build Coastguard Worker  });
252*c8dee2aaSAndroid Build Coastguard Worker</script>