f679d1bf38
BUG=skia: R=robertphillips@google.com Author: jcgregorio@google.com Review URL: https://codereview.chromium.org/177963005 git-svn-id: http://skia.googlecode.com/svn/trunk@13615 2bbb7eff-a529-9590-31e7-b0007b416f81
96 lines
1.8 KiB
JavaScript
96 lines
1.8 KiB
JavaScript
var IS_SKV8 = typeof document == "undefined";
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var HAS_PATH = typeof Path2D != "undefined";
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function circlePath(r) {
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if (HAS_PATH) {
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var p = new Path2D();
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p.arc(0, 0, r, 0, 2*Math.PI);
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p.closePath();
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return p;
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} else {
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return null;
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}
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}
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var onDraw = function() {
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var W = 500;
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var H = 500;
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var NumParticles = 100;
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var angle = 0;
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var ticks = 0;
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var particles =[];
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for (var i = 0; i < NumParticles; i++) {
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particles[i] = {
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x: Math.floor(Math.random()*W),
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y: Math.floor(Math.random()*H),
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r: Math.floor(Math.random()*7+1),
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path: circlePath(Math.random()*7+1),
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}
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}
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function draw(ctx) {
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ctx.fillStyle = "#ADD8E6";
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ctx.fillRect(0, 0, W-1, H-1);
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ctx.fillStyle = "#FFFFFF";
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angle += 0.0039;
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for (var i = 0; i < particles.length; i++) {
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var p = particles[i];
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p.x += Math.floor(Math.sin(angle)*5.0);
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p.y += 0.6*p.r;
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if (p.x > W) {
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p.x-=W;
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}
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if (p.x < 0) {
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p.x += W;
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}
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if(p.y>(H+1)){
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p.y = 0;
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}
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if (HAS_PATH) {
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ctx.save();
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ctx.translate(p.x, p.y);
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ctx.fill(p.path);
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ctx.restore();
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} else {
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ctx.beginPath();
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ctx.moveTo(p.x, p.y);
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ctx.arc(p.x, p.y, p.r, 0, 2*Math.PI, true);
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ctx.closePath();
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ctx.fill();
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}
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};
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ticks++;
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if (IS_SKV8) {
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inval();
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}
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}
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function fps() {
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console.log(ticks);
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ticks = 0;
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setTimeout(fps, 1000);
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}
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setTimeout(fps, 1000);
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return draw;
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}();
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if (!IS_SKV8) {
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window.onload = function(){
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var canvas = document.getElementById("snow");
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var ctx = canvas.getContext("2d");
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function drawCallback() {
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onDraw(ctx);
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setTimeout(drawCallback, 1);
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}
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setTimeout(drawCallback, 1);
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}
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}
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console.log("HAS_PATH: " + HAS_PATH);
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