LayoutTests/webgl/2.0.0/resources/webgl_test_files/conformance/context/context-hidden-alpha.html - WebKit - Git at Google

 <!--

 /*
 ** Copyright (c) 2014 The Khronos Group Inc.
 **
 ** Permission is hereby granted, free of charge, to any person obtaining a
 ** copy of this software and/or associated documentation files (the
 ** "Materials"), to deal in the Materials without restriction, including
 ** without limitation the rights to use, copy, modify, merge, publish,
 ** distribute, sublicense, and/or sell copies of the Materials, and to
 ** permit persons to whom the Materials are furnished to do so, subject to
 ** the following conditions:
 **
 ** The above copyright notice and this permission notice shall be included
 ** in all copies or substantial portions of the Materials.
 **
 ** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 ** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 ** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
 */

 -->

 <!DOCTYPE html>
 <html>
 <head>
 <meta charset="utf-8">
 <link rel="stylesheet" href="../../resources/js-test-style.css"/>
 <script src="../../js/js-test-pre.js"></script>
 <script src="../../js/webgl-test-utils.js"></script>
 <script id='vs' type='x-shader/x-vertex'>
     attribute vec2 aPosCoord;

     void main(void) {
         gl_Position = vec4(aPosCoord, 0.0, 1.0);
     }
 </script>

 <script id='fs' type='x-shader/x-fragment'>
     precision mediump float;

     void main(void) {
         gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
     }
 </script>
 <script>
 "use strict";

 var posCoords_arr = new Float32Array(2 * 4);
 var posCoords_buff = null;
 function DrawQuad(gl, prog, x0, y0, x1, y1) {
     gl.useProgram(prog);

     if (!posCoords_buff) {
         posCoords_buff = gl.createBuffer();
     }
     gl.bindBuffer(gl.ARRAY_BUFFER, posCoords_buff);
     posCoords_arr[0] = x0;
     posCoords_arr[1] = y0;

     posCoords_arr[2] = x1;
     posCoords_arr[3] = y0;

     posCoords_arr[4] = x0;
     posCoords_arr[5] = y1;

     posCoords_arr[6] = x1;
     posCoords_arr[7] = y1;
     gl.bufferData(gl.ARRAY_BUFFER, posCoords_arr, gl.STREAM_DRAW);

     gl.enableVertexAttribArray(prog.aPosCoord);
     gl.vertexAttribPointer(prog.aPosCoord, 2, gl.FLOAT, false, 0, 0);

     gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
 }

 function DrawSquare(gl, prog, size) {
     DrawQuad(gl, prog, -size, -size, size, size);
 }

 function Reset(gl) {
     gl.canvas.width += 1;
     gl.canvas.width -= 1;
 }

 var iColor;
 var pixel;
 var dataURL_pre;
 var dataURL_post;

 function Test(gl, prog, shouldFinish) {
     gl.enable(gl.BLEND);
     gl.blendFunc(gl.ZERO, gl.DST_ALPHA);

     iColor = 64;
     var fColor = iColor / 255.0;

     //////////////////

     debug('clear(R,G,B,0)');

     Reset(gl);

     gl.clearColor(fColor, fColor, fColor, 0.0);
     gl.clear(gl.COLOR_BUFFER_BIT);

     dataURL_pre = gl.canvas.toDataURL();
     //console.log('Before blending: ' + dataURL_pre);

     DrawSquare(gl, prog, 0.7);

     WebGLTestUtils.checkCanvasRect(gl, gl.drawingBufferWidth/2,
                                    gl.drawingBufferHeight/2, 1, 1,
                                    [iColor, iColor, iColor, 255],
                                    'Should blend as if alpha is 1.0.');

     dataURL_post = gl.canvas.toDataURL();
     //console.log('After blending: ' + dataURL_post);
     shouldBe("dataURL_post", "dataURL_pre");

     //////////////////

     debug('mask(R,G,B,0), clear(R,G,B,1)');

     Reset(gl);

     gl.colorMask(true, true, true, false);
     gl.clearColor(fColor, fColor, fColor, 1.0);
     gl.clear(gl.COLOR_BUFFER_BIT);
     gl.colorMask(true, true, true, true);

     dataURL_pre = gl.canvas.toDataURL();
     //console.log('Before blending: ' + dataURL_pre);

     DrawSquare(gl, prog, 0.7);

     WebGLTestUtils.checkCanvasRect(gl, gl.drawingBufferWidth/2,
                                    gl.drawingBufferHeight/2, 1, 1,
                                    [iColor, iColor, iColor, 255],
                                    'Should blend as if alpha is 1.0.');

     dataURL_post = gl.canvas.toDataURL();
     //console.log('After blending: ' + dataURL_post);
     shouldBe("dataURL_post", "dataURL_pre");

     ////////////////

     WebGLTestUtils.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");

     if (shouldFinish)
         finishTest();
 }

 var gl;
 function init() {
     var canvas = document.getElementById('canvas');
     var attribs = {
         alpha: false,
         antialias: false,
         premultipliedAlpha: false,
     };
     gl = canvas.getContext('experimental-webgl', attribs);
     shouldBeNonNull(gl);
     shouldBe("gl.getParameter(gl.ALPHA_BITS)", "0");

     var prog = WebGLTestUtils.setupProgram(gl, ['vs', 'fs']);
     shouldBeNonNull(prog);
     prog.aPosCoord = gl.getAttribLocation(prog, 'aPosCoord');

     Test(gl, prog, false);

     requestAnimationFrame(function(){ Test(gl, prog, true); });
 }

 </script>
 </head>
 <body onload="init()">
 <canvas id='canvas'></canvas>
 <br/>
 <div id="description"></div>
 <div id="console"></div>
 </body>
 </html>
	<!--

	/*
	** Copyright (c) 2014 The Khronos Group Inc.
	**
	** Permission is hereby granted, free of charge, to any person obtaining a
	** copy of this software and/or associated documentation files (the
	** "Materials"), to deal in the Materials without restriction, including
	** without limitation the rights to use, copy, modify, merge, publish,
	** distribute, sublicense, and/or sell copies of the Materials, and to
	** permit persons to whom the Materials are furnished to do so, subject to
	** the following conditions:
	**
	** The above copyright notice and this permission notice shall be included
	** in all copies or substantial portions of the Materials.
	**
	** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
	** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
	** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
	** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
	** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
	*/

	-->

	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<link rel="stylesheet" href="../../resources/js-test-style.css"/>
	<script src="../../js/js-test-pre.js"></script>
	<script src="../../js/webgl-test-utils.js"></script>
	<script id='vs' type='x-shader/x-vertex'>
	attribute vec2 aPosCoord;

	void main(void) {
	gl_Position = vec4(aPosCoord, 0.0, 1.0);
	}
	</script>

	<script id='fs' type='x-shader/x-fragment'>
	precision mediump float;

	void main(void) {
	gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
	}
	</script>
	<script>
	"use strict";

	var posCoords_arr = new Float32Array(2 * 4);
	var posCoords_buff = null;
	function DrawQuad(gl, prog, x0, y0, x1, y1) {
	gl.useProgram(prog);

	if (!posCoords_buff) {
	posCoords_buff = gl.createBuffer();
	}
	gl.bindBuffer(gl.ARRAY_BUFFER, posCoords_buff);
	posCoords_arr[0] = x0;
	posCoords_arr[1] = y0;

	posCoords_arr[2] = x1;
	posCoords_arr[3] = y0;

	posCoords_arr[4] = x0;
	posCoords_arr[5] = y1;

	posCoords_arr[6] = x1;
	posCoords_arr[7] = y1;
	gl.bufferData(gl.ARRAY_BUFFER, posCoords_arr, gl.STREAM_DRAW);

	gl.enableVertexAttribArray(prog.aPosCoord);
	gl.vertexAttribPointer(prog.aPosCoord, 2, gl.FLOAT, false, 0, 0);

	gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4);
	}

	function DrawSquare(gl, prog, size) {
	DrawQuad(gl, prog, -size, -size, size, size);
	}

	function Reset(gl) {
	gl.canvas.width += 1;
	gl.canvas.width -= 1;
	}

	var iColor;
	var pixel;
	var dataURL_pre;
	var dataURL_post;

	function Test(gl, prog, shouldFinish) {
	gl.enable(gl.BLEND);
	gl.blendFunc(gl.ZERO, gl.DST_ALPHA);

	iColor = 64;
	var fColor = iColor / 255.0;

	//////////////////

	debug('clear(R,G,B,0)');

	Reset(gl);

	gl.clearColor(fColor, fColor, fColor, 0.0);
	gl.clear(gl.COLOR_BUFFER_BIT);

	dataURL_pre = gl.canvas.toDataURL();
	//console.log('Before blending: ' + dataURL_pre);

	DrawSquare(gl, prog, 0.7);

	WebGLTestUtils.checkCanvasRect(gl, gl.drawingBufferWidth/2,
	gl.drawingBufferHeight/2, 1, 1,
	[iColor, iColor, iColor, 255],
	'Should blend as if alpha is 1.0.');

	dataURL_post = gl.canvas.toDataURL();
	//console.log('After blending: ' + dataURL_post);
	shouldBe("dataURL_post", "dataURL_pre");

	//////////////////

	debug('mask(R,G,B,0), clear(R,G,B,1)');

	Reset(gl);

	gl.colorMask(true, true, true, false);
	gl.clearColor(fColor, fColor, fColor, 1.0);
	gl.clear(gl.COLOR_BUFFER_BIT);
	gl.colorMask(true, true, true, true);

	dataURL_pre = gl.canvas.toDataURL();
	//console.log('Before blending: ' + dataURL_pre);

	DrawSquare(gl, prog, 0.7);

	WebGLTestUtils.checkCanvasRect(gl, gl.drawingBufferWidth/2,
	gl.drawingBufferHeight/2, 1, 1,
	[iColor, iColor, iColor, 255],
	'Should blend as if alpha is 1.0.');

	dataURL_post = gl.canvas.toDataURL();
	//console.log('After blending: ' + dataURL_post);
	shouldBe("dataURL_post", "dataURL_pre");

	////////////////

	WebGLTestUtils.glErrorShouldBe(gl, gl.NO_ERROR, "should be no errors");

	if (shouldFinish)
	finishTest();
	}

	var gl;
	function init() {
	var canvas = document.getElementById('canvas');
	var attribs = {
	alpha: false,
	antialias: false,
	premultipliedAlpha: false,
	};
	gl = canvas.getContext('experimental-webgl', attribs);
	shouldBeNonNull(gl);
	shouldBe("gl.getParameter(gl.ALPHA_BITS)", "0");

	var prog = WebGLTestUtils.setupProgram(gl, ['vs', 'fs']);
	shouldBeNonNull(prog);
	prog.aPosCoord = gl.getAttribLocation(prog, 'aPosCoord');

	Test(gl, prog, false);

	requestAnimationFrame(function(){ Test(gl, prog, true); });
	}

	</script>
	</head>
	<body onload="init()">
	<canvas id='canvas'></canvas>
	<br/>
	<div id="description"></div>
	<div id="console"></div>
	</body>
	</html>