| <!DOCTYPE html> |
| <html> |
| <head> |
| <title>WebGL pixelStorei Test</title> |
| <script src="../../../resources/js-test.js"></script> |
| <script src="resources/webgl-test.js"> </script> |
| <script src="resources/desktop-gl-constants.js" type="text/javascript"></script> |
| </head> |
| <body> |
| <canvas id="example" width="50" height="50"></canvas> |
| <canvas id="2d00" width="50" height="50"></canvas> |
| <canvas id="2d01" width="50" height="50"></canvas> |
| <canvas id="2d02" width="50" height="50"></canvas> |
| <canvas id="2d03" 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(1.0,0.0,0.0,1.0); |
| } |
| </script> |
| |
| <script> |
| function fail(x,y, name, buf, shouldBe) { |
| var i = (y*50+x) * 4; |
| var reason = "pixel in "+name+" at ("+x+","+y+") is ("+buf[i]+","+buf[i+1]+","+buf[i+2]+","+buf[i+3]+"), should be "+shouldBe; |
| testFailed(reason); |
| } |
| |
| function pass(name) { |
| testPassed("drawing is correct in " + name); |
| } |
| |
| function init() { |
| debug("There should be 5 red triangles on 5 black squares above"); |
| debug(""); |
| |
| debug("This test checks that drawImage and readPixels are not effected by gl.Pixelstorei(gl.PACK_ALIGNMENT) and visa versa"); |
| debug(""); |
| |
| var canvas3d = document.getElementById("example"); |
| gl = initWebGL("example", "vshader", "fshader", [ "vPosition"], [ 0, 0, 0, 1 ], 1); |
| |
| var vertexObject = gl.createBuffer(); |
| gl.bindBuffer(gl.ARRAY_BUFFER, vertexObject); |
| gl.bufferData(gl.ARRAY_BUFFER, new Float32Array([ 0,0.5,0, -0.5,-0.5,0, 0.5,-0.5,0 ]), gl.STATIC_DRAW); |
| gl.enableVertexAttribArray(0); |
| gl.vertexAttribPointer(0, 3, gl.FLOAT, false, 0, 0); |
| |
| gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT); |
| gl.drawArrays(gl.TRIANGLES, 0, 3); |
| |
| |
| function checkData(buf, name) { |
| // Test several locations |
| // First line should be all black |
| for (var i = 0; i < 50; ++i) { |
| if (buf[i*4] != 0 || buf[i*4+1] != 0 || buf[i*4+2] != 0 || buf[i*4+3] != 255) { |
| fail(i, 0, name, buf, "(0,0,0,255)"); |
| return; |
| } |
| } |
| |
| // Line 25 should be red for at least 6 red pixels starting 22 pixels in |
| var offset = (25*50+22) * 4; |
| for (var i = 0; i < 6; ++i) { |
| if (buf[offset+i*4] != 255 || buf[offset+i*4+1] != 0 || buf[offset+i*4+2] != 0 || buf[offset+i*4+3] != 255) { |
| fail(22 + i, 25, name, buf, "(255,0,0,255)"); |
| return; |
| } |
| } |
| |
| // Last line should be all black |
| offset = (49*50) * 4; |
| for (var i = 0; i < 50; ++i) { |
| if (buf[offset+i*4] != 0 || buf[offset+i*4+1] != 0 || buf[offset+i*4+2] != 0 || buf[offset+i*4+3] != 255) { |
| fail(i, 49, name, buf, "(0,0,0,255)"); |
| return; |
| } |
| } |
| |
| pass(name); |
| } |
| |
| function checkColors() { |
| var buf = new Uint8Array(50 * 50 * 4); |
| gl.readPixels(0, 0, 50, 50, gl.RGBA, gl.UNSIGNED_BYTE, buf); |
| checkData(buf, "3d context"); |
| var imgData = ctx2d.getImageData(0, 0, 50, 50); |
| checkData(imgData.data, "2d context"); |
| } |
| |
| var table = [1, 2, 4, 8]; |
| for (var ii = 0; ii < table.length; ++ii) { |
| gl.pixelStorei(gl.PACK_ALIGNMENT, table[ii]); |
| ctx2d = document.getElementById("2d0" + ii).getContext("2d"); |
| ctx2d.globalCompositeOperation = 'copy'; |
| ctx2d.drawImage(canvas3d, 0, 0); |
| checkColors(); |
| assertMsg(gl.getParameter(gl.PACK_ALIGNMENT) == table[ii], |
| "PACK_ALIGNMENT is " + table[ii]); |
| } |
| } |
| |
| init(); |
| </script> |
| </body> |
| </html> |
