| <!-- |
| Copyright (c) 2019 The Khronos Group Inc. |
| Use of this source code is governed by an MIT-style license that can be |
| found in the LICENSE.txt file. |
| --> |
| |
| <!DOCTYPE html> |
| <html> |
| <head> |
| <meta charset="utf-8"> |
| <title>WebGL Enable Vertex Attrib Zero Test</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> |
| <canvas id="example" width="50" height="50"> |
| </canvas> |
| <div id="description"></div> |
| <div id="console"></div> |
| <script id="vshader" type="x-shader/x-vertex"> |
| attribute vec4 vPosition; |
| void main() |
| { |
| gl_Position = vPosition; |
| } |
| </script> |
| |
| <script id="fshader" type="x-shader/x-fragment"> |
| void main() |
| { |
| gl_FragColor = vec4(0.0,1.0,0.0,1.0); |
| } |
| </script> |
| |
| <script> |
| "use strict"; |
| description("Test some of the issues of the difference between attrib 0 on OpenGL vs WebGL"); |
| debug(""); |
| var wtu = WebGLTestUtils; |
| var gl = wtu.create3DContext("example"); |
| var g_program; |
| var g_attribLocation; |
| function setup(attribIndex) { |
| var program = wtu.setupProgram( |
| gl, ['vshader', 'fshader'], ['vPosition'], [attribIndex]); |
| g_program = program; |
| g_attribLocation = attribIndex; |
| shouldBe("g_attribLocation", "gl.getAttribLocation(g_program, 'vPosition')"); |
| return program; |
| } |
| |
| function setupVerts(numVerts) { |
| var verts = [ |
| 1.0, 1.0, 0.0, |
| -1.0, 1.0, 0.0, |
| -1.0, -1.0, 0.0, |
| 1.0, 1.0, 0.0, |
| -1.0, -1.0, 0.0, |
| 1.0, -1.0, 0.0 |
| ]; |
| var positions = new Float32Array(numVerts * 3); |
| var indices = new Uint16Array(numVerts); |
| for (var ii = 0; ii < numVerts; ++ii) { |
| var ndx = ii % 6; |
| var dst = ii * 3; |
| var src = ndx * 3; |
| for (var jj = 0; jj < 3; ++jj) { |
| positions[dst + jj] = verts[src + jj]; |
| } |
| indices[ii] = ii; |
| } |
| var vertexObject = gl.createBuffer(); |
| gl.bindBuffer(gl.ARRAY_BUFFER, vertexObject); |
| gl.bufferData(gl.ARRAY_BUFFER, positions, gl.STATIC_DRAW); |
| var indexBuffer = gl.createBuffer(); |
| gl.bindBuffer(gl.ELEMENT_ARRAY_BUFFER, indexBuffer); |
| gl.bufferData(gl.ELEMENT_ARRAY_BUFFER, indices, gl.STATIC_DRAW); |
| } |
| |
| var p0 = setup(0); |
| var p3 = setup(3); |
| setupVerts(60000); |
| |
| for (var ii = 0; ii < 5; ++ii) { |
| // test drawing with attrib 0 |
| gl.useProgram(p0); |
| gl.enableVertexAttribArray(0); |
| gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| gl.drawElements(gl.TRIANGLES, 60000, gl.UNSIGNED_SHORT, 0); |
| wtu.glErrorShouldBe( |
| gl, gl.NO_ERROR, |
| "drawing using attrib 0 with 6 verts"); |
| wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green"); |
| gl.disableVertexAttribArray(0); |
| |
| // test drawing without attrib 0 |
| gl.useProgram(p3); |
| gl.enableVertexAttribArray(3); |
| gl.vertexAttribPointer(3, 3, gl.FLOAT, false, 0, 0); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| gl.drawArrays(gl.TRIANGLES, 0, 60000); |
| wtu.glErrorShouldBe( |
| gl, gl.NO_ERROR, |
| "drawing using attrib 3 with 60000 verts"); |
| wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green"); |
| gl.disableVertexAttribArray(3); |
| |
| // This second test of drawing without attrib0 uncovered a bug in chrome |
| // where after the draw without attrib0 the attrib 0 emulation code disabled |
| // attrib 0 and it was never re-enabled so this next draw failed. |
| gl.useProgram(p3); |
| gl.enableVertexAttribArray(3); |
| gl.clear(gl.COLOR_BUFFER_BIT); |
| gl.drawElements(gl.TRIANGLES, 60000, gl.UNSIGNED_SHORT, 0); |
| wtu.glErrorShouldBe( |
| gl, gl.NO_ERROR, |
| "drawing using attrib 3 with 60000 verts"); |
| wtu.checkCanvas(gl, [0, 255, 0, 255], "canvas should be green"); |
| gl.disableVertexAttribArray(3); |
| } |
| |
| |
| var successfullyParsed = true; |
| </script> |
| <script src="../../js/js-test-post.js"></script> |
| |
| </body> |
| </html> |
| |
