Test case details

Preparation Code

<canvas id="cvs2d" width="1024" height="768"></canvas> <canvas id="cvs3d" width="1024" height="768"></canvas>
var img, tex, vloc, tloc,vertexBuff, texBuff;         var cvs2d = document.getElementById('cvs2d');     var cvs3d = document.getElementById('cvs3d');     var ctx2d = cvs2d.getContext('2d');     var ctx3d = cvs3d.getContext('experimental-webgl');             // create shaders     var vertexShaderSrc =     "attribute vec2 aVertex;" +     "attribute vec2 aUV;" +     "varying vec2 vTex;" +     "void main(void) {" +     "  gl_Position = vec4(aVertex, 0.0, 1.0);" +     "  vTex = aUV;" +     "}";         var fragmentShaderSrc =     "precision highp float;" +     "varying vec2 vTex;" +     "uniform sampler2D sampler0;" +     "void main(void){" +     "  gl_FragColor = texture2D(sampler0, vTex);"+     "}";         var vertShaderObj = ctx3d.createShader(ctx3d.VERTEX_SHADER);     var fragShaderObj = ctx3d.createShader(ctx3d.FRAGMENT_SHADER);     ctx3d.shaderSource(vertShaderObj, vertexShaderSrc);     ctx3d.shaderSource(fragShaderObj, fragmentShaderSrc);     ctx3d.compileShader(vertShaderObj);     ctx3d.compileShader(fragShaderObj);         var progObj = ctx3d.createProgram();     ctx3d.attachShader(progObj, vertShaderObj);     ctx3d.attachShader(progObj, fragShaderObj);         ctx3d.linkProgram(progObj);     ctx3d.useProgram(progObj);         ctx3d.viewport(0, 0, 1024, 768);         vertexBuff = ctx3d.createBuffer();     ctx3d.bindBuffer(ctx3d.ARRAY_BUFFER, vertexBuff);     ctx3d.bufferData(ctx3d.ARRAY_BUFFER, new Float32Array([-1/8, 1/6, -1/8, -1/6, 1/8, -1/6, 1/8, 1/6]), ctx3d.STATIC_DRAW);         texBuff = ctx3d.createBuffer();     ctx3d.bindBuffer(ctx3d.ARRAY_BUFFER, texBuff);     ctx3d.bufferData(ctx3d.ARRAY_BUFFER, new Float32Array([0, 1, 0, 0, 1, 0, 1, 1]), ctx3d.STATIC_DRAW);         vloc = ctx3d.getAttribLocation(progObj, "aVertex");     tloc = ctx3d.getAttribLocation(progObj, "aUV");         img = new Image();     img.src = 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        img.onload = function(){       tex = ctx3d.createTexture();       ctx3d.bindTexture(ctx3d.TEXTURE_2D, tex);       ctx3d.pixelStorei(ctx3d.UNPACK_FLIP_Y_WEBGL, true);       ctx3d.texParameteri(ctx3d.TEXTURE_2D, ctx3d.TEXTURE_MIN_FILTER, ctx3d.NEAREST);       ctx3d.texParameteri(ctx3d.TEXTURE_2D, ctx3d.TEXTURE_MAG_FILTER, ctx3d.NEAREST);       ctx3d.generateMipmap(ctx3d.TEXTURE_2D);       ctx3d.texImage2D(ctx3d.TEXTURE_2D, 0,  ctx3d.RGBA,  ctx3d.RGBA, ctx3d.UNSIGNED_BYTE, this);         ctx3d.enableVertexAttribArray(vloc);     ctx3d.bindBuffer(ctx3d.ARRAY_BUFFER, vertexBuff);     ctx3d.vertexAttribPointer(vloc, 2, ctx3d.FLOAT, false, 0, 0);         ctx3d.enableVertexAttribArray(tloc);     ctx3d.bindBuffer(ctx3d.ARRAY_BUFFER, texBuff);     ctx3d.bindTexture(ctx3d.TEXTURE_2D, tex);     ctx3d.vertexAttribPointer(tloc, 2, ctx3d.FLOAT, false, 0, 0);     };

Test cases

Test #1

ctx2d.drawImage(img, 0, 0);

Test #2

ctx3d.drawArrays(ctx3d.TRIANGLE_FAN, 0, 4);