| <!-- |
| |
| /* |
| ** Copyright (c) 2012 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"> |
| <title>WebGL short-circuit evaluation</title> |
| <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> |
| </head> |
| <body> |
| <div id="description"></div> |
| <div id="console"></div> |
| <canvas id="example" width="2" height="2"> </canvas> |
| |
| <!------------------------------------- |
| WebGL Shaders |
| ----------------------------------------> |
| <!-- Pass through Shaders --> |
| <script id="vshader0" type="x-shader/x-vertex"> |
| /* PASS-THROUGH VERTEX SHADER */ |
| attribute vec4 vPosition; |
| |
| void main() |
| { |
| gl_Position = vPosition; |
| } |
| </script> |
| |
| <script id="fshader0" type="x-shader/x-fragment"> |
| /* PASS-THROUGH FRAGMENT SHADER */ |
| precision mediump float; |
| varying vec4 vPassThrough; |
| |
| void main() |
| { |
| gl_FragColor = vPassThrough; |
| } |
| </script> |
| |
| <!-- basic conditonal short circuit Shaders --> |
| <script id="vshader1" type="x-shader/x-vertex"> |
| attribute vec4 vPosition; |
| varying vec4 vPassThrough; |
| |
| void main() |
| { |
| int x = 1; |
| $(variables) |
| |
| if ($(condition)) |
| { /*do nothing*/ } |
| |
| /* if x was unmodified return green, else return red */ |
| vPassThrough = (x == 1) ? vec4(0, 1, 0, 1) : vec4(1, 0, 0, 1); |
| gl_Position = vPosition; |
| } |
| </script> |
| |
| <script id="fshader1" type="x-shader/x-fragment"> |
| precision mediump float; |
| |
| void main() |
| { |
| int x = 1; |
| $(variables) |
| |
| if ($(condition)) |
| { /*do nothing*/ } |
| |
| gl_FragColor = (x == 1) ? vec4(0, 1, 0, 1) : vec4(1, 0, 0, 1); |
| } |
| </script> |
| |
| <!-- Main body of the Webgl program --> |
| <script> |
| "use strict"; |
| description(); |
| |
| var wtu = WebGLTestUtils; |
| var gl = wtu.create3DContext(); |
| |
| wtu.setupUnitQuad(gl, [0, 1]); |
| |
| var shaderTemplates = [ |
| { vs: "vshader1", fs: "fshader0" }, // basic vertex short-circuit test |
| { vs: "vshader0", fs: "fshader1" }, // basic fragment short-circuit test |
| ]; |
| |
| /* replace the names of the shaders in the tempate variables with |
| * the shaders themselves */ |
| for (var ii = 0; ii < shaderTemplates.length; ++ii) { |
| var template = shaderTemplates[ii]; |
| template.vs = wtu.getScript(template.vs); |
| template.fs = wtu.getScript(template.fs); |
| } |
| |
| /* define the conditon that will be used in the shaders. If additional |
| * variables are needed that are not present i the shader they my be |
| * defined in the variables variable */ |
| var tests = [ |
| { condition: "true || (x = 0) == 1", variables: "" }, /* test basic 'or' short circuit */ |
| { condition: "false && (x = 0) == 1", variables: "" }, /* test basic 'and' short circuit */ |
| { condition: "(j == 3 && j == k) || (j > (x = 0))", variables: "int j = 3;\nint k = 3;" }, /* test basic 'or' short circuit with actual condition */ |
| { condition: "(j == 3 && j == k) && (j > (x = 0))", variables: "int j = 3;\nint k = 4;" }, /* test basic 'and' short circuit with actual condition */ |
| { condition: "(j + 3 > k && ((j < 10) || (x + 5 > j + (x = 0))) || ( x = 0 ) == 7)", variables: "int j = 5;\nint k = 3;" }, /* complex test */ |
| { condition: "j + 1 == 6 ? x == 1 || j > (x = 0) : (x = 0) == 1 && (x = 0) <= 1", variables: "int j = 5;" }, /* nested with ternary operator */ |
| { condition: "true && (true || (x = 0) == 1)", variables: "" }, /* test unfold short circuit update order correctness */ |
| ]; |
| |
| function testShortCircuit(test) { |
| debug(""); |
| debug("testing short circuit condition: " + test.condition); |
| |
| /* Setting clear color to blue */ |
| gl.clearColor(0.0, 0.0, 1.0, 1.0); |
| |
| for (var ii = 0; ii < shaderTemplates.length; ++ii) { |
| |
| /* clear the screen so that subsequent tests don't conflict */ |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| var template = shaderTemplates[ii]; |
| |
| var vs = wtu.replaceParams(template.vs, test); |
| var fs = wtu.replaceParams(template.fs, test); |
| |
| var program = wtu.setupProgram(gl, [vs, fs], ['vPosition'], undefined, true); |
| |
| wtu.clearAndDrawUnitQuad(gl); |
| wtu.checkCanvas(gl, [0, 255, 0, 255], "should be green", 0); |
| |
| gl.deleteProgram(program); |
| |
| wtu.glErrorShouldBe(gl, gl.NO_ERROR, "should be no GL errors"); |
| } |
| } |
| |
| var testNdx = 0; |
| function runNextTest() { |
| testShortCircuit(tests[testNdx++]); |
| if (testNdx >= tests.length) { |
| finishTest(); |
| } else { |
| setTimeout(runNextTest, 0); |
| } |
| } |
| |
| runNextTest(); |
| </script> |
| </body> |
| </html> |