[Piglit] [PATCH 3/4] Add test to verify sample alpha to coverage with multisample fbo
Paul Berry
stereotype441 at gmail.com
Sat Jun 16 07:55:30 PDT 2012
On 8 June 2012 14:45, <anuj.phogat at gmail.com> wrote:
> From: Anuj Phogat <anuj.phogat at gmail.com>
>
> This test varifies that with GL_SAMPLE_ALPHA_TO_COVERAGE enabled, the
> coverage
> value is set by fragment alpha value. Coverage value decides the number of
> samples in multisample buffer covered by an incoming fragment, which
> receive
> the fragment data.
>
> It also includes testing of sample alpha to coverage with
> GL_SAMPLE_ALPHA_TO_ONE
> enabled/disabled.
>
> Note: Test fails for depth buffer on NVIDIA's proprietary drivers. Depth
> buffer is
> not modified even if the incoming multisample fragment passes the
> depth test
> and has a coverage = 1.0.
>
Most of my comments from the previous patch apply to this patch as well.
>
> Signed-off-by: Anuj Phogat <anuj.phogat at gmail.com>
> ---
> tests/all.tests | 7 +
> .../ext_framebuffer_multisample/CMakeLists.gl.txt | 1 +
> .../sample-alpha-to-coverage.cpp | 375
> ++++++++++++++++++++
> 3 files changed, 383 insertions(+), 0 deletions(-)
> create mode 100644
> tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp
>
> diff --git a/tests/all.tests b/tests/all.tests
> index a52b745..0e531b8 100644
> --- a/tests/all.tests
> +++ b/tests/all.tests
> @@ -1393,6 +1393,13 @@ for num_samples in (2, 4, 8, 16, 32):
> test_name)
> ext_framebuffer_multisample[test_name] =
> PlainExecTest(executable)
>
> +for num_samples in (2, 4, 8, 16, 32):
> + for buffer_type in ('color', 'depth'):
> + test_name = ' '.join(['sample-alpha-to-coverage',
> str(num_samples), buffer_type])
> + executable = 'ext_framebuffer_multisample-{0}
> -auto'.format(
> + test_name)
> + ext_framebuffer_multisample[test_name] =
> PlainExecTest(executable)
> +
> ext_framebuffer_object = Group()
> spec['EXT_framebuffer_object'] = ext_framebuffer_object
> add_fbo_stencil_tests(ext_framebuffer_object, 'GL_STENCIL_INDEX1')
> diff --git a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
> b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
> index 17a9571..a6595fa 100644
> --- a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
> +++ b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
> @@ -27,6 +27,7 @@ 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-turn-on-off common.cpp
> turn-on-off.cpp)
> piglit_add_executable (ext_framebuffer_multisample-unaligned-blit
> common.cpp unaligned-blit.cpp)
> piglit_add_executable (ext_framebuffer_multisample-upsample common.cpp
> upsample.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
> new file mode 100644
> index 0000000..59a365b
> --- /dev/null
> +++ b/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage.cpp
> @@ -0,0 +1,375 @@
> +/*
> + * Copyright © 2012 Intel Corporation
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a
> + * copy of this software and associated documentation files (the
> "Software"),
> + * to deal in the Software without restriction, including without
> limitation
> + * the rights to use, copy, modify, merge, publish, distribute,
> sublicense,
> + * and/or sell copies of the Software, and to permit persons to whom the
> + * Software is furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice (including the
> next
> + * paragraph) shall be included in all copies or substantial portions of
> the
> + * Software.
> + *
> + * THE SOFTWARE IS 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 SOFTWARE OR THE USE OR OTHER
> DEALINGS
> + * IN THE SOFTWARE.
> + */
> +
> +#include "common.h"
> +
> +/**
> + * \file sample-alpha-to-coverage.cpp
> + *
> + * Verify glSampleCoverage() with and without coverage mask invert
> + *
> + * This test operates by drawing test pattern in a multisample FBO with
> + * GL_SAMPLE_ALPHA_TO_COVERAGE disabled.
> + *
> + * Blit the multisample_fbo to right half of window system framebuffer.
> + * This is used as reference image to see the visual difference caused by
> + * the alpha value.
> + *
> + * Compute the expected color values based on the coverage value used to
> + * draw the test pattern.
> + *
> + * Clear the multisample framebuffer to a unique color/depth. Draws
> + * the same test pattern for the second time 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 left half
> + * of window system framebuffer. This is the test image.
> + *
> + * Probe the left half of window syetem framebuffer and compare with
> expected
> + * color values.
> + *
> + * Repeat the above testing with GL_SAMPLE_ALPHA_TO_ONE enabled as well.
> + *
> + * Author: Anuj Phogat <anuj.phogat at gmail.com>
> + */
> +
> +int piglit_width = 512; int piglit_height = 256;
> +int piglit_window_mode =
> + GLUT_DOUBLE | GLUT_RGBA | GLUT_ALPHA | GLUT_DEPTH;
> +const int pattern_width = 256; const int pattern_height = 256;
> +
> +static Fbo ms_fbo, resolve_fbo;
> +static GLint num_samples;
> +static float expected[4][4];
> +static float coverage[4];
> +static GLbitfield buffer_to_test;
> +
> +static const float bg_depth = 0.80;
> +static const float bg_color[4] =
> + {0.0, 0.0, 1.0, 0.8};
> +
> +static const float depth[4] =
> + {0.0, 0.25, 0.60, 0.70};
> +
> +static const float color[4][4] = {
> + /* Red */
> + {1.0, 0.0, 0.0, 0.0},
> + /* Green */
> + {0.0, 1.0, 0.0, 0.25},
> + /* Yellow */
> + {1.0, 1.0, 0.0, 0.75},
> + /* Cyan */
> + {0.0, 1.0, 1.0, 1.0} };
> +
> +static GLint prog;
> +static GLint color_loc;
> +static GLint depth_loc;
> +
> +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)
> +{
> + float vertex_data[10][2] = {
> + { 0, 0 },
> + { 0, pattern_height },
> + { pattern_width / 4, pattern_height },
> + { pattern_width / 4, 0 },
> + { pattern_width / 2, pattern_height },
> + { pattern_width / 2, 0 },
> + { 3 * pattern_width / 4, pattern_height },
> + { 3 * pattern_width / 4, 0 },
> + { pattern_width, pattern_height },
> + { pattern_width, 0 },
> + };
> +
> + unsigned int indices[24] = {0, 1, 2, 0, 2, 3,
> + 3, 2, 4, 3, 4, 5,
> + 5, 4, 6, 5, 6, 7,
> + 7, 6, 8, 7, 8, 9};
> + 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);
> +
> + glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE,
> sizeof(vertex_data[0]),
> + (void *) vertex_data);
> +
> + for (int i = 0; i < 4; ++i) {
> + glUniform4fv(color_loc, 1, color[i]);
> + glUniform1f(depth_loc, depth[i]);
> + glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT,
> + (void *) (indices + 6 * i));
> + }
> + 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> <buffer_type>\n"
> + " where <buffer_type> is one of:\n"
> + " color\n"
> + " depth\n",
> + prog_name);
> + piglit_report_result(PIGLIT_FAIL);
> +}
> +
> +void
> +compute_expected(bool sample_alpha_to_one)
> +{
> + int i, j;
> +
> + /* Fragment's alpha value is directly used as coverage value */
> + for (i = 0; i < 4; i++)
> + coverage[i] = color[i][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 < 4; i++) {
> + for (j = 0; j < 4; j++)
> + expected[i][j] = color[i][j] * coverage[i]
> +
> + bg_color[j] * (1 -
> coverage[i]);
> +
> + if (sample_alpha_to_one)
> + expected[i][3] = 1.0 * coverage[i] +
> + bg_color[3] * (1 -
> coverage[i]);
> + }
> + }
> + /* Compute the expected depth values only for coverage = 0.0 and
> 1.0 */
> + else if(buffer_to_test == GL_DEPTH_BUFFER_BIT) {
> + for (i = 0; i < 4; i++) {
> + if (coverage[i] == 0.0)
> + expected[0][i] = bg_depth;
> + else if (coverage[i] == 1.0)
> + expected[0][i] = depth[i] < bg_depth ?
> + depth[i] : bg_depth;
> + }
> + }
> +}
> +
> +bool
> +probe_framebuffer_color(void)
> +{
> + bool result = true;
> + glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
> + for (int i = 0; i < 4; i++) {
> + result = piglit_probe_rect_rgba(i * (pattern_width / 4),
> + 0,
> + pattern_width / 4,
> + pattern_height,
> + expected[i])
> + && result;
> + }
> + return result;
> +}
> +
> +bool
> +probe_framebuffer_depth(void)
> +{
> + bool result = true;
> + glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
> + for (int i = 0; i < 4; i++) {
> + if(coverage[i] == 0.0 || coverage[i] == 1.0)
> + result = piglit_probe_rect_depth(i *
> (pattern_width / 4),
> + 0,
> + pattern_width / 4,
> + pattern_height,
> + expected[0][i])
> + && result;
> + else
> + /*Skip probing polygons which are drawn with
> coverage
> + * value between 0.0 and 1.0
> + */
> + continue;
> + }
> + return result;
> +}
> +
> +bool
> +test_sample_alpha_to_coverage(bool sample_alpha_to_one)
> +{
> + bool result = true;
> + compute_expected(sample_alpha_to_one);
> + /* Now draw test pattern in mulisample ms_fbo with
> GL_SAMPLE_ALPHA_TO_COVERAGE
> + * enabled
> + */
> + glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle);
> + draw_pattern(true, 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 left 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 left half of default framebuffer and compare to the
> + * expected values */
> + if (buffer_to_test == GL_COLOR_BUFFER_BIT)
> + result = probe_framebuffer_color() && result;
> + else if (buffer_to_test == GL_DEPTH_BUFFER_BIT)
> + result = probe_framebuffer_depth() && result;
> +
> + result = piglit_check_gl_error(GL_NO_ERROR) && result;
> + return result;
> +}
> +
> +
> +void
> +piglit_init(int argc, char **argv)
> +{
> + if (argc < 3)
> + print_usage_and_exit(argv[0]);
> + {
> + char *endptr = NULL;
> + num_samples = strtol(argv[1], &endptr, 0);
> + if (endptr != argv[1] + strlen(argv[1]))
> + print_usage_and_exit(argv[0]);
> + }
> +
> + piglit_require_gl_version(30);
> + piglit_ortho_projection(pattern_width, pattern_height, GL_TRUE);
> +
> + /* Skip the test if num_samples > GL_MAX_SAMPLES or num_samples =
> 0 */
> + GLint max_samples;
> + glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
> + if (num_samples > max_samples ||
> + num_samples == 0)
> + piglit_report_result(PIGLIT_SKIP);
> +
> + ms_fbo.setup(FboConfig(num_samples, pattern_width,
> pattern_height));
> + resolve_fbo.setup(FboConfig(num_samples, pattern_width,
> pattern_height));
> +
> + if (strcmp(argv[2], "color") == 0) {
> + buffer_to_test = GL_COLOR_BUFFER_BIT;
> + } else if (strcmp(argv[2], "depth") == 0) {
> + buffer_to_test = GL_DEPTH_BUFFER_BIT;
> + glClearDepth(bg_depth);
> + glEnable(GL_DEPTH_TEST);
> + } else
> + print_usage_and_exit(argv[0]);
> +
> + shader_compile();
> +}
> +
> +enum piglit_result
> +piglit_display()
> +{
> + bool pass = true;
> + glClearColor(0.0, 0.0, 0.0, 1.0);
> + glClear(GL_COLOR_BUFFER_BIT);
> +
> + /* Draw test pattern in multisample ms_fbo with GL_POLYGON_SMOOTH
> + * disabled.
> + */
> + glBindFramebuffer(GL_DRAW_FRAMEBUFFER, ms_fbo.handle);
> + ms_fbo.set_viewport();
> + draw_pattern(false, false);
> +
> + /* Blit ms_fbo to the right half of window system framebuffer. This
> + * is a reference image to test MSAA with polygon smooth.
> + */
> + glBindFramebuffer(GL_READ_FRAMEBUFFER, ms_fbo.handle);
> + glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
> + glBlitFramebuffer(0, 0, pattern_width, pattern_height,
> + pattern_width, 0, 2 * pattern_width,
> pattern_height,
> + buffer_to_test, GL_NEAREST);
> +
> + /* Test with GL_SAMPLE_ALPHA_TO_ONE disabled
> + */
> + pass = test_sample_alpha_to_coverage(false /* sample_alpha_to_one
> */)
> + && pass;
> +
> + /* Test with GL_SAMPLE_ALPHA_TO_ONE enabled */
> + pass = test_sample_alpha_to_coverage(true /* sample_alpha_to_one
> */)
> + && pass;
> +
> + if (!piglit_automatic &&
> + buffer_to_test != GL_DEPTH_BUFFER_BIT)
> + piglit_present_results();
> +
> + return pass ? PIGLIT_PASS : PIGLIT_FAIL;
> +}
> --
> 1.7.7.6
>
>
> _______________________________________________
> Piglit mailing list
> Piglit at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/piglit
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freedesktop.org/archives/piglit/attachments/20120616/1a1b0ecc/attachment-0001.html>
More information about the Piglit
mailing list