Lot of the functions defined in this test case are also shared by draw-buffers-common.cpp. So this refactoring is done to avoid code duplication.
Signed-off-by: Anuj Phogat <anuj.pho...@gmail.com> --- .../ext_framebuffer_multisample/CMakeLists.gl.txt | 3 +- .../sample-alpha-to-coverage.cpp | 372 +++----------------- 2 files changed, 49 insertions(+), 326 deletions(-) diff --git a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt index ee12e68..f2e366a 100644 --- a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt +++ b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt @@ -47,7 +47,8 @@ piglit_add_executable (ext_framebuffer_multisample-renderbuffer-samples renderbu piglit_add_executable (ext_framebuffer_multisample-renderbufferstorage-samples renderbufferstorage-samples.c) piglit_add_executable (ext_framebuffer_multisample-samples samples.c) piglit_add_executable (ext_framebuffer_multisample-sample-coverage common.cpp sample-coverage.cpp) -piglit_add_executable (ext_framebuffer_multisample-sample-alpha-to-coverage common.cpp sample-alpha-to-coverage.cpp) +piglit_add_executable (ext_framebuffer_multisample-sample-alpha-to-coverage common.cpp + draw-buffers-common.cpp sample-alpha-to-coverage.cpp) piglit_add_executable (ext_framebuffer_multisample-sample-alpha-to-one common.cpp sample-alpha-to-one.cpp) piglit_add_executable (ext_framebuffer_multisample-turn-on-off common.cpp turn-on-off.cpp) piglit_add_executable (ext_framebuffer_multisample-unaligned-blit common.cpp unaligned-blit.cpp) diff --git a/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp b/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp index 28ae633..b8ccf5d 100644 --- a/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp +++ b/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp @@ -21,311 +21,45 @@ * IN THE SOFTWARE. */ -#include "common.h" +#include "draw-buffers-common.h" /** * \file sample-alpha-to-coverage.cpp * - * Verify GL_SAMPLE_ALPHA_TO_COVERAGE with multisample FBO. + * Verify sample alpha to coverage with multisample FBO * - * This test operates by drawing a test pattern to multisample_fbo with - * GL_SAMPLE_ALPHA_TO_COVERAGE disabled. + * When rendering to multiple draw buffers, fragment's alpha value should be + * used to determine the coverage value. * - * Blit the multisample_fbo to top half of window system framebuffer. This - * is used as reference image to visually compare the difference caused by - * sample alpha to coverage value. + * This test operates by drawing a pattern in multisample FBO to generate + * reference and test image. Reference image is drawn to right half of window + * system frame buffer and test image to left half. * - * Compute the expected color values based on the coverage value used to - * draw the test pattern. + * Compute the expected color / depth values. * - * Clear the multisample framebuffer to a unique color. Draw the same test - * pattern in multisample buffer with GL_SAMPLE_ALPHA_TO_COVERAGE enabled. - * Resolve the multisample FBO by blitting it to a single sample FBO. Blit - * the resolve_fbo to bottom half of window system framebuffer. This is our - * test image. - * - * Probe the rectangles in bottom half of window system framebuffer and - * compare with expected color values. OpenGL 3.0 specification intends - * to allow (but not require) the implementation to produce a dithering - * effect when the coverage value is not a strict multiple of 1/num_samples. - * We will skip computing expected values and probing for such rectangles. - * They are drawn just to look for dithering by human inspection. - * - * Repeat the above testing with GL_SAMPLE_ALPHA_TO_ONE enabled / disabled. - * when both GL_SAMPLE_ALPHA_TO_ONE and GL_SAMPLE_ALPHA_TO_COVERAGE are - * enabled, GL_SAMPLE_ALPHA_TO_COVERAGE takes effect first. i.e. the - * coverage value is computed from the alpha value before the alpha value - * is changed to 1. - * - * Note: glSampleCoverage() takes effect in the graphics pipeline before - * the point where the output of the fragment shader is split into the - * various buffers. So it's very likely that if glSampleCoverage() works - * properly for color buffers, it will work properly for depth and stencil - * buffers too. + * Probe color / depth buffer blitted to downsampled FBO (resolve_fbo) and + * compare against expected color values. * * Author: Anuj Phogat <anuj.pho...@gmail.com> */ PIGLIT_GL_TEST_MAIN(512 /*window_width*/, - 256 /*window_height*/, + 768 /*window_height*/, GLUT_DOUBLE | GLUT_RGBA | GLUT_ALPHA) -const int pattern_width = 512; const int pattern_height = 128; -static Fbo ms_fbo, resolve_fbo; -static GLbitfield buffer_to_test; - -static float *coverage = NULL; -static float *color = NULL; -static float *expected = NULL; - -static int num_samples; -static int num_rects; -static int prog; -static int color_loc; -static int depth_loc; - -static const float bg_color[4] = { 0.4, 0.6, 0.0, 0.8 }; - -static const char *vert = - "#version 130\n" - "in vec2 pos;\n" - "uniform float depth;\n" - "void main()\n" - "{\n" - " vec4 eye_pos = gl_ModelViewProjectionMatrix * vec4(pos, 0.0, 1.0);\n" - " gl_Position = vec4(eye_pos.xy, depth, 1.0);\n" - "}\n"; - -static const char *frag = - "#version 130\n" - "uniform vec4 color;\n" - "void main()\n" - "{\n" - " gl_FragColor = color;\n" - "}\n"; - -void -shader_compile() -{ - /* Compile program */ - GLint vs = piglit_compile_shader_text(GL_VERTEX_SHADER, vert); - GLint fs = piglit_compile_shader_text(GL_FRAGMENT_SHADER, frag); - prog = piglit_link_simple_program(vs, fs); - - if (!piglit_link_check_status(prog)) { - piglit_report_result(PIGLIT_FAIL); - } - - glBindAttribLocation(prog, 0, "pos"); - glEnableVertexAttribArray(0); - - /* Set up uniforms */ - glUseProgram(prog); - color_loc = glGetUniformLocation(prog, "color"); - depth_loc = glGetUniformLocation(prog, "depth"); -} - -void -draw_pattern(bool sample_alpha_to_coverage, bool sample_alpha_to_one) -{ - glUseProgram(prog); - glClearColor(bg_color[0], bg_color[1], - bg_color[2], bg_color[3]); - glClear(buffer_to_test); - - if (sample_alpha_to_coverage) - glEnable (GL_SAMPLE_ALPHA_TO_COVERAGE); - - if (sample_alpha_to_one) - glEnable (GL_SAMPLE_ALPHA_TO_ONE); - - unsigned int indices[6] = {0, 1, 2, 0, 2, 3}; - - for (int i = 0; i < num_rects; ++i) { - - float vertex_data[4][2] = { - { 0.0f + i * (pattern_width / num_rects), 0.0f }, - { 0.0f + i * (pattern_width / num_rects), pattern_height }, - { (i + 1.0f) * (pattern_width / num_rects), pattern_height }, - { (i + 1.0f) * (pattern_width / num_rects), 0.0f } }; - - glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, - sizeof(vertex_data[0]), - (void *) vertex_data); - - glUniform4fv(color_loc, 1, (color + i * 4)); - glUniform1f(depth_loc, 0.0f); - glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, - (void *) indices); - } - if (sample_alpha_to_coverage) - glDisable (GL_SAMPLE_ALPHA_TO_COVERAGE); - - if (sample_alpha_to_one) - glDisable (GL_SAMPLE_ALPHA_TO_ONE); -} - void print_usage_and_exit(char *prog_name) { - printf("Usage: %s <num_samples>\n", prog_name); + printf("Usage: %s <num_samples>\n", prog_name); piglit_report_result(PIGLIT_FAIL); } void -compute_expected(bool sample_alpha_to_one) -{ - int i, j; - - /* Sample alpha to coverage doesn't affect single sample FBO */ - if(num_samples == 0) { - for(i = 0; i < 4; i++) - expected[i] = color[i]; - return; - } - - /* Fragment's alpha value is directly used as coverage value */ - for (i = 0; i < num_rects; i++) - coverage[i] = color[i * 4 + 3]; - - /* Coverage value decides the number of samples in multisample buffer - * covered by an incoming fragment, which will then receive the fragment - * data. When the multisample buffer is resolved it will be blended - * with the background color which will be written to the remaining - * samples. - * Page 254 (page 270 of the PDF) of the OpenGL 3.0 spec says: - * "The method of combination is not specified, though a simple average - * computed independently for each color component is recommended." - */ - if(buffer_to_test == GL_COLOR_BUFFER_BIT) { - for (i = 0; i < num_rects; i++) { - - float samples_used = coverage[i] * num_samples; - /* Exepected color values are computed only for integer - * number of samples_used - */ - if(samples_used == (int)samples_used) { - - for(j =0; j < 4; j++) - expected[i * 4 + j] = - color[i * 4 + j] * coverage[i] + - bg_color[j] * (1 - coverage[i]); - - if (sample_alpha_to_one) - expected[i * 4 + 3] = - 1.0 * coverage[i] + - bg_color[3] * (1 - coverage[i]); - } - } - } -} - -bool -probe_framebuffer_color(bool sample_alpha_to_one) -{ - bool result = true; - glBindFramebuffer(GL_READ_FRAMEBUFFER, 0); - - for (int i = 0; i < num_rects; i++) { - float samples_used = coverage[i] * num_samples; - - /* Only probe rectangles with coverage value which is a strict - * multiple of 1 / num_samples. - */ - if(samples_used == (int)samples_used) { - result = piglit_probe_rect_rgba( - i * (pattern_width / num_rects), - 0, - pattern_width / num_rects, - pattern_height, - expected + i * 4) - && result; - } - } - return result; -} - -bool -test_sample_alpha_to_coverage(bool sample_alpha_to_one) -{ - bool result = true; - compute_expected(sample_alpha_to_one); - - /* Draw test pattern in multisample ms_fbo with - * GL_SAMPLE_ALPHA_TO_COVERAGE enabled - */ - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle); - draw_pattern(true /* sample_alpha_to_coverage */ , sample_alpha_to_one); - - /* Blit ms_fbo to resolve_fbo to resolve multisample buffer */ - glBindFramebuffer(GL_READ_FRAMEBUFFER, ms_fbo.handle); - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, resolve_fbo.handle); - glBlitFramebuffer(0, 0, pattern_width, pattern_height, - 0, 0, pattern_width, pattern_height, - buffer_to_test, GL_NEAREST); - - /* Blit resolve_fbo to the bottom half of window system framebuffer. - * This is the test image. - */ - glBindFramebuffer(GL_READ_FRAMEBUFFER, resolve_fbo.handle); - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0); - glBlitFramebuffer(0, 0, pattern_width, pattern_height, - 0, 0, pattern_width, pattern_height, - buffer_to_test, GL_NEAREST); - - /* Probe the bottom half of default framebuffer and compare to the - * expected values */ - if (buffer_to_test == GL_COLOR_BUFFER_BIT) - result = probe_framebuffer_color(sample_alpha_to_one) && result; - - result = piglit_check_gl_error(GL_NO_ERROR) && result; - return result; -} - -void -allocate_data_arrays(void) -{ - /* Draw 2N + 1 rectangles for N samples, each with a unique color - * and coverage value - */ - num_rects = 2 * num_samples + 1; - - /* Allocate data arrays based on number of samples used */ - color = (float *) malloc(num_rects * 4 * sizeof(float)); - coverage = (float *) malloc(num_rects * sizeof(float)); - expected = (float *) malloc(num_rects * 4 * sizeof(float)); - - for(int i = 0; i < num_rects; i++) { - color[i * 4 + 0] = (sin((float)(i * 4 + 0)) + 1) / 2; - color[i * 4 + 1] = (sin((float)(i * 4 + 1)) + 1) / 2; - color[i * 4 + 2] = (sin((float)(i * 4 + 2)) + 1) / 2; - - /* Alpha value will be used as coverage */ - color[i * 4 + 3] = i * (1.0 / (2 * num_samples)); - } -} - -void -free_data_arrays(void) -{ - if(color != NULL) { - free(color); - color = NULL; - } - if(coverage != NULL) { - free(coverage); - coverage = NULL; - } - if(expected != NULL) { - free(expected); - expected = NULL; - } -} - -void piglit_init(int argc, char **argv) { int samples; + int num_attachments = 1; + if (argc < 2) print_usage_and_exit(argv[0]); { @@ -336,7 +70,13 @@ piglit_init(int argc, char **argv) } piglit_require_gl_version(30); - piglit_ortho_projection(pattern_width, pattern_height, GL_TRUE); + + int pattern_width = piglit_width / 2; + int pattern_height = piglit_height / num_attachments; + + piglit_ortho_projection(pattern_width, + pattern_height, + GL_TRUE); /* Skip the test if samples > GL_MAX_SAMPLES */ GLint max_samples; @@ -345,24 +85,12 @@ piglit_init(int argc, char **argv) if (samples > max_samples) piglit_report_result(PIGLIT_SKIP); - /* Setup frame buffer objects with required configuration */ - ms_fbo.setup(FboConfig(samples, pattern_width, pattern_height)); - resolve_fbo.setup(FboConfig(0, pattern_width, pattern_height)); - - if (!piglit_check_gl_error(GL_NO_ERROR)) { - printf("Error setting up frame buffer objects\n"); - piglit_report_result(PIGLIT_FAIL); - } - - /* Query the number of samples used in ms_fbo. OpenGL implementation - * may create FBO with more samples per pixel than what is requested. - */ - glBindRenderbuffer(GL_RENDERBUFFER, ms_fbo.color_rb); - glGetRenderbufferParameteriv(GL_RENDERBUFFER, - GL_RENDERBUFFER_SAMPLES, - &num_samples); - - buffer_to_test = GL_COLOR_BUFFER_BIT; + ms_fbo_and_draw_buffers_setup(samples, + pattern_width, + pattern_height, + num_attachments, + GL_COLOR_BUFFER_BIT, + GL_RGBA); shader_compile(); } @@ -370,43 +98,37 @@ enum piglit_result piglit_display() { bool pass = true; - allocate_data_arrays(); - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0); glClearColor(0.0, 0.0, 0.0, 1.0); - glClear(buffer_to_test); + glClear(GL_COLOR_BUFFER_BIT); + allocate_data_arrays(); - /* Draw test pattern in multisample ms_fbo with - * GL_SAMPLE_ALPHA_TO_COVERAGE disabled. + /* Reference image drawn when sample_alpha_to_coverage is enabled, + * doesn't represent an expected image. Reference image is drawn only + * to visualize the image difference caused by enabling + * sample_alpha_to_coverage */ - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle); - ms_fbo.set_viewport(); - draw_pattern(false /* sample_alpha_to_coverage */, - false /* sample_alpha_to_one */ ); + draw_reference_image(true /* sample_alpha_to_coverage */, + false /* sample_alpha_to_one */); - /* Blit ms_fbo to the top half of window system framebuffer. This - * is our reference image to visually compare the effect of MSAA - * with sample alpha to coverage. - */ - glBindFramebuffer(GL_READ_FRAMEBUFFER, ms_fbo.handle); - glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0); - glBlitFramebuffer(0, 0, - pattern_width, pattern_height, - 0, pattern_height, - pattern_width, 2 * pattern_height, - buffer_to_test, GL_NEAREST); + draw_test_image(true /* sample_alpha_to_coverage */, + false /* sample_alpha_to_one */); - /* Test with sample_alpha_to_one = false */ - pass = test_sample_alpha_to_coverage(false) && pass; + pass = piglit_check_gl_error(GL_NO_ERROR) && pass; - /* Test sample alpha to coverage with sample_alpha_to_one = true */ - pass = test_sample_alpha_to_coverage(true) && pass; + /* Probe all the test image blitted to resolve fbo and compare with + * expected color values. This method of verification is appropriate + * for tests with sample-alpha-to-coverage enabled. Possibility of + * dithering effect when the coverage value is not a strict multiple + * of 1 / num_samples makes image compare (test / reference image) + * unsuitable for this test. + */ + pass = probe_framebuffer_color() && pass; /* Free the memory allocated for data arrays */ free_data_arrays(); - if (!piglit_automatic && - buffer_to_test != GL_DEPTH_BUFFER_BIT) + if (!piglit_automatic) piglit_present_results(); return pass ? PIGLIT_PASS : PIGLIT_FAIL; -- 1.7.7.6 _______________________________________________ Piglit mailing list Piglit@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/piglit