Cleaned up OpenGLUI samples and added Blasteroids.

samples/openglui/src/openglui_canvas_tests.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Canvas API tests. Some of these are adapted from:
 //
 // http://www.html5canvastutorials.com/
 
 library openglui_canvas_tests;
 
 import 'gl.dart';
 import 'dart:math' as Math;
 
 var ctx;
 var width, height;
 bool isDirty = true;
 var canvas;
 
 void resize(int w, int h) {
   width = w;
   height = h;
 }
 
-void setup(canvasp, int w, int h) {
+void setup(canvasp, int w, int h, int f) {
   if (canvasp == null) {
     log("Allocating canvas");
     canvas = new CanvasElement(width: w, height: h);
     document.body.nodes.add(canvas);
   } else {
     log("Using parent canvas");
     canvas = canvasp;
   }
   canvas.onMouseDown.listen((e) {
     ++testnum;
@@ skipping 458 matching lines @@
   ctx.setLineDash([]);
   ctx.strokeStyle = "#0000FF";
   ctx.strokeStyle = "rgba(128,128,128, 0.5)";
   ctx.strokeRect(width / 5, height / 10, width / 2, height / 8);
   log("Width = $width");
 }
 
 void loadImage() {
   initTest("Image loading");
   var imageObj = new ImageElement();
-  var sub;
-  sub = imageObj.onLoad.listen((e) {
-    ctx.drawImage(e.target, 69, 50);
-    sub.cancel();
+  // Setting src before onLoad is a more interesting test.
+  imageObj.src = 'chrome.png';
+  imageObj.onLoad.listen((e) {
+    ctx.drawImage(e.target, 0, 0, width, height, 0, 0, width, height);
   });
-  imageObj.src = 'chrome.png';
 }
 
 void clip() {
   initTest("Clipping");
   var x = width / 2;
   var y = height / 2;
   var radius = height / 4;
   var offset = 2 * radius / 3;
 
   ctx.save();
@@ skipping 130 matching lines @@
 
   ctx.beginPath();
   ctx.rect(myRectangle.x, myRectangle.y, myRectangle.width, myRectangle.height);
   ctx.fillStyle = '#8ED6FF';
   ctx.fill();
   ctx.lineWidth = myRectangle.borderWidth;
   ctx.strokeStyle = 'black';
   ctx.stroke();
 }
 
+void linearGradient() {
+  initTest("Linear Gradient");
+  ctx.rect(0, 0, width, height);
+  var grd = ctx.createLinearGradient(0, 0, width, height);
+  // light blue
+  grd.addColorStop(0, '#8ED6FF');   
+  // dark blue
+  grd.addColorStop(1, '#004CB3');
+  ctx.fillStyle = grd;
+  ctx.fill();
+}
+
+void radialGradient() {
+  initTest("Radial Gradient");
+  ctx.rect(0, 0, width, height);
+  var grd = ctx.createRadialGradient(238, 50, 10, 238, 50, 300);
+  // light blue
+  grd.addColorStop(0, '#8ED6FF');
+  // dark blue
+  grd.addColorStop(1, '#004CB3');
+  ctx.fillStyle = grd;
+  ctx.fill();
+}
+
 int testnum = 0; // Set this to -1 to start with last test.
 
+double x, y, z;
+
+onAccelerometer(double xx, double yy, double zz) {
+ x = xx;
+ y = yy;
+ z = zz;
+}
+
 void update(num when) {
   window.requestAnimationFrame(update);
   if (testnum == 0) {
     anim();
     return;
   }
   if (!isDirty) return;
   switch(testnum) {
     case 1:
       helloWorld();
@@ skipping 55 matching lines @@
     case 20:
       shear();
       break;
     case 21:
       composite();
       break;
     case 22:
       smiley();
       break;
     case 23:
+      linearGradient();
+      break;
+    case 24:
+      radialGradient();
+      break;
+    case 25:
+      break; // Skip for now; this is really slow.
       var rayTracer = new RayTracer();
       rayTracer.render(defaultScene(), ctx, width, height);
       break;
     default:
       if (testnum < 0) {
-        testnum = 23;
+        testnum = 24;
       } else {
         testnum = 0;
       }
       return;
   }
+
   isDirty = false;
 }
 
 // Raytracer adapted from https://gist.github.com/mythz/3817303.
 
 Scene defaultScene() =>
    new Scene(
       [new Plane(new Vector(0.0, 1.0, 0.0), 0.0, Surfaces.checkerboard),
        new Sphere(new Vector(0.0, 1.0, -0.25), 1.0, Surfaces.shiny),
        new Sphere(new Vector(-1.0, 0.5, 1.5), 0.5, Surfaces.shiny)],
@@ skipping 242 matching lines @@
       for (int x = 0; x < screenWidth; x++) {
         var color = _traceRay(new Ray(scene.camera.pos,
             getPoint(x, y, scene.camera) ), scene, 0);
         ctx.fillStyle = Color.toDrawingRGB(color);
         ctx.fillRect(x, y, x + 1, y + 1);
       }
     }
   }
 }