| <!DOCTYPE html> |
| <html> |
| <head> |
| <meta charset="utf-8"> |
| <link rel="stylesheet" href="resources/webgl_test_files/resources/js-test-style.css"/> |
| <script src="resources/webgl_test_files/js/js-test-pre.js"></script> |
| <script src="resources/webgl_test_files/js/webgl-test-utils.js"></script> |
| </head> |
| <body onload="test()"> |
| <div id="description"></div> |
| <div id="console"></div> |
| <canvas id="canvas" width="2" height="2"></canvas> |
| <script> |
| "use strict"; |
| description("Test that modifying READ_FRAMEBUFFER does not affect DRAW_FRAMEBUFFER state."); |
| |
| var wtu = WebGLTestUtils; |
| var gl; |
| |
| function test() |
| { |
| var canvas = document.getElementById("canvas"); |
| gl = wtu.create3DContext(canvas, undefined, 2); |
| |
| if (!gl) { |
| testFailed("WebGL2 context does not exist"); |
| finishTest(); |
| return; |
| } |
| |
| var vertexShaderSource = `#version 300 es |
| layout(location=0) in highp vec4 a_position; |
| void main() { gl_Position = a_position; }`; |
| |
| var fragmentShaderSource = `#version 300 es |
| precision highp float; |
| out ivec4 outColor0; |
| void main() { outColor0.a = 1; }`; |
| |
| var program = wtu.setupProgram(gl, [vertexShaderSource, fragmentShaderSource]); |
| if (!program) { |
| testFailed("Failed to create program"); |
| finishTest(); |
| return; |
| } |
| |
| // Verify initial state |
| shouldBe("gl.getParameter(gl.DRAW_BUFFER0)", "gl.BACK"); |
| |
| // Create framebuffer and set its draw buffers to COLOR_ATTACHMENT0 |
| var framebuffer = gl.createFramebuffer(); |
| gl.bindFramebuffer(gl.DRAW_FRAMEBUFFER, framebuffer); |
| gl.drawBuffers([gl.COLOR_ATTACHMENT0]); // Set explicit draw buffer state |
| gl.bindFramebuffer(gl.DRAW_FRAMEBUFFER, null); |
| |
| // Set default framebuffer draw buffer to NONE |
| gl.drawBuffers([gl.NONE]); |
| shouldBe("gl.getParameter(gl.DRAW_BUFFER0)", "gl.NONE"); |
| |
| // Bind framebuffer to READ_FRAMEBUFFER only |
| gl.bindFramebuffer(gl.READ_FRAMEBUFFER, framebuffer); |
| shouldBe("gl.getParameter(gl.DRAW_FRAMEBUFFER_BINDING)", "null"); |
| |
| // Attach texture to READ_FRAMEBUFFER (should NOT corrupt DRAW_FRAMEBUFFER state) |
| var texture = gl.createTexture(); |
| gl.bindTexture(gl.TEXTURE_2D, texture); |
| gl.framebufferTexture2D(gl.READ_FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, texture, 0); |
| wtu.glErrorShouldBe(gl, gl.NO_ERROR, "framebufferTexture2D should succeed"); |
| |
| // Verify draw buffer state was not corrupted |
| shouldBe("gl.getParameter(gl.DRAW_BUFFER0)", "gl.NONE"); |
| |
| // Draw should succeed |
| gl.drawArrays(gl.TRIANGLE_STRIP, 0, 4); |
| wtu.glErrorShouldBe(gl, gl.NO_ERROR, "drawArrays should succeed"); |
| |
| // Verify draw buffer state is still preserved |
| shouldBe("gl.getParameter(gl.DRAW_BUFFER0)", "gl.NONE"); |
| |
| finishTest(); |
| } |
| </script> |
| </body> |
| </html> |
