[Piglit] [PATCH] msaa: add test to verify alpha-to-coverage together with alpha-to-one

Brian Paul brianp at vmware.com
Fri Aug 4 15:36:36 UTC 2017


On 08/04/2017 09:30 AM, Brian Paul wrote:
> On 08/04/2017 08:51 AM, Roland Scheidegger wrote:
>> Am 04.08.2017 um 16:43 schrieb Brian Paul:
>>> On 08/04/2017 08:32 AM, sroland at vmware.com wrote:
>>>> From: Roland Scheidegger <sroland at vmware.com>
>>>>
>>>> I believe the sole reason alpha-to-one exists at all is that it can be
>>>> used together with alpha-to-coverage (otherwise why not just output
>>>> alpha
>>>> 1.0 in the fs in the first place...).
>>>> Therefore, it seems quite appropriate to test this together with
>>>> alpha-to-coverage.
>>>>
>>>> Note: the test is a simple copy of sample-alpha-to-coverage with only
>>>> trivial adjustments. I don't think the common code used actually
>>>> handles
>>>> this case correctly for the reference image (as it's the same as when
>>>> just using alpha-to-coverage, which can't be right), but I haven't
>>>> looked
>>>> at it long enough to be able to fix it.
>>>> It is, however, good enough to pass on my nvidia card, albeit some mesa
>>>> drivers trying to emulate this feature are definitely broken (I'm
>>>> looking
>>>> at you radeons...).
>>>> ---
>>>>    tests/all.py                                       |   5 +
>>>>    .../ext_framebuffer_multisample/CMakeLists.gl.txt  |   2 +
>>>>    .../sample-alpha-to-coverage-one.cpp               | 162
>>>> +++++++++++++++++++++
>>>>    3 files changed, 169 insertions(+)
>>>>    create mode 100644
>>>> tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage-one.cpp
>>>>
>>>> diff --git a/tests/all.py b/tests/all.py
>>>> index fc00d99..bc5b9e0 100644
>>>> --- a/tests/all.py
>>>> +++ b/tests/all.py
>>>> @@ -3028,6 +3028,11 @@ with profile.test_list.group_manager(
>>>>                   sample_count, buffer_type],
>>>>                  'sample-alpha-to-coverage {} {}'.format(
>>>>                      sample_count, buffer_type))
>>>> +
>>>> g(['ext_framebuffer_multisample-sample-alpha-to-coverage-one',
>>>> +               sample_count, buffer_type],
>>>> +              'sample-alpha-to-coverage-one {} {}'.format(
>>>> +                  sample_count, buffer_type))
>>>> +
>>>>
>>>>            for test in ['line-smooth', 'point-smooth',
>>>> 'polygon-smooth',
>>>>                         'sample-alpha-to-one',
>>>> diff --git a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
>>>> b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
>>>> index 6841267..e93c609 100644
>>>> --- a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
>>>> +++ b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
>>>> @@ -62,6 +62,8 @@ 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
>>>>                   draw-buffers-common.cpp sample-alpha-to-coverage.cpp)
>>>> +piglit_add_executable
>>>> (ext_framebuffer_multisample-sample-alpha-to-coverage-one common.cpp
>>>> +               draw-buffers-common.cpp
>>>> sample-alpha-to-coverage-one.cpp)
>>>>    piglit_add_executable
>>>> (ext_framebuffer_multisample-sample-alpha-to-one common.cpp
>>>>                   draw-buffers-common.cpp sample-alpha-to-one.cpp)
>>>>    piglit_add_executable (ext_framebuffer_multisample-turn-on-off
>>>> common.cpp turn-on-off.cpp)
>>>> diff --git
>>>> a/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage-one.cpp
>>>>
>>>> b/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage-one.cpp
>>>>
>>>> new file mode 100644
>>>> index 0000000..887893a
>>>> --- /dev/null
>>>> +++
>>>> b/tests/spec/ext_framebuffer_multisample/sample-alpha-to-coverage-one.cpp
>>>>
>>>> @@ -0,0 +1,162 @@
>>>> +/*
>>>> + * 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 "draw-buffers-common.h"
>>>> +
>>>> +/**
>>>> + * \file sample-alpha-to-coverage.cpp
>>>> + *
>>>> + * Verify sample alpha to coverage plus alpha to one with multisample
>>>> FBO
>>>> + *
>>>> + * When rendering to multisample FBO, fragment's alpha value should be
>>>> + * used to determine the coverage value, and then the alpha value set
>>>> to 1.
>>>> + *
>>>> + * 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 / depth values.
>>>> + *
>>>> + * Probe color / depth buffer blitted to downsampled FBO
>>>> (resolve_fbo) and
>>>> + * compare against expected color values.
>>>> + *
>>>> + * Author: Anuj Phogat <anuj.phogat at gmail.com>
>>>> + */
>>>> +
>>>> +PIGLIT_GL_TEST_CONFIG_BEGIN
>>>> +
>>>> +    config.supports_gl_compat_version = 10;
>>>> +
>>>> +    config.window_width = 512;
>>>> +    config.window_height = 256;
>>>> +    config.window_visual = PIGLIT_GL_VISUAL_DOUBLE |
>>>> PIGLIT_GL_VISUAL_RGBA;
>>>> +
>>>> +PIGLIT_GL_TEST_CONFIG_END
>>>> +
>>>> +static GLenum buffer_to_test;
>>>> +
>>>> +void
>>>> +print_usage_and_exit(char *prog_name)
>>>> +{
>>>> +    printf("Usage: %s <num_samples> <test_type>\n"
>>>> +           "  where <test_type> is one of:\n"
>>>> +           "    color\n"
>>>> +           "    depth\n",
>>>> +           prog_name);
>>>> +    piglit_report_result(PIGLIT_FAIL);
>>>> +}
>>>> +
>>>> +void
>>>> +piglit_init(int argc, char **argv)
>>>> +{
>>>> +    const int num_attachments = 1;
>>>> +    int samples;
>>>> +
>>>> +    piglit_require_gl_version(21);
>>>> +    piglit_require_extension("GL_ARB_framebuffer_object");
>>>> +    piglit_require_extension("GL_ARB_vertex_array_object");
>>>> +
>>>> +    if (argc < 3)
>>>> +        print_usage_and_exit(argv[0]);
>>>> +    {
>>>> +        char *endptr = NULL;
>>>> +        samples = strtol(argv[1], &endptr, 0);
>>>> +        if (endptr != argv[1] + strlen(argv[1]))
>>>> +            print_usage_and_exit(argv[0]);
>>>> +    }
>>>> +    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;
>>>> +        glEnable(GL_DEPTH_TEST);
>>>> +        glDepthFunc(GL_ALWAYS);
>>>> +    } else
>>>> +        print_usage_and_exit(argv[0]);
>>>> +
>>>> +    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;
>>>> +    glGetIntegerv(GL_MAX_SAMPLES, &max_samples);
>>>> +
>>>> +    if (samples > max_samples)
>>>> +        piglit_report_result(PIGLIT_SKIP);
>>>> +
>>>> +    ms_fbo_and_draw_buffers_setup(samples,
>>>> +                      pattern_width,
>>>> +                      pattern_height,
>>>> +                      num_attachments,
>>>> +                      buffer_to_test,
>>>> +                      GL_RGBA);
>>>> +    shader_compile(true /* sample_alpha_to_coverage */,
>>>> +               false /* dual_src_blend */,
>>>> +               true /* frag_out_zero_write */);
>>>> +}
>>>> +
>>>> +enum piglit_result
>>>> +piglit_display()
>>>> +{
>>>> +    bool pass = true;
>>>> +    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
>>>> +    glClearColor(0.0, 0.0, 0.0, 1.0);
>>>> +    glClear(GL_COLOR_BUFFER_BIT);
>>>> +    allocate_data_arrays();
>>>> +
>>>> +    /* Reference image drawn here doesn't represent an expected image.
>>>> +     * Reference image is drawn only to visualize the image difference
>>>> +     * caused by enabling sample_alpha_to_coverage in test image.
>>>> +     */
>>>> +    if(buffer_to_test == GL_COLOR_BUFFER_BIT)
>>>> +        draw_reference_image(true /* sample_alpha_to_coverage */,
>>>> +                     true /* sample_alpha_to_one */);
>>>> +
>>>> +    draw_test_image(true /* sample_alpha_to_coverage */,
>>>> +            true /* sample_alpha_to_one */);
>>>> +
>>>> +    pass = piglit_check_gl_error(GL_NO_ERROR) && 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.
>>>> +     */
>>>> +    if(buffer_to_test == GL_COLOR_BUFFER_BIT)
>>>> +        pass = probe_framebuffer_color() && pass;
>>>> +    else if (buffer_to_test == GL_DEPTH_BUFFER_BIT)
>>>> +        pass = probe_framebuffer_depth() && pass;
>>>> +
>>>> +    /* Free the memory allocated for data arrays */
>>>> +    free_data_arrays();
>>>> +
>>>> +    if (!piglit_automatic && buffer_to_test == GL_COLOR_BUFFER_BIT)
>>>> +        piglit_present_results();
>>>> +
>>>> +    return pass ? PIGLIT_PASS : PIGLIT_FAIL;
>>>> +}
>>>>
>>>
>>> I have a patch in my tree for testing the same thing.
>>>
>>> I've cleaned it up and attached it below.  What do you think?  Less
>>> code.
>>>
>>
>> Yes, much better, I'll drop this then. (I was actually wondering why the
>> alpha-to-one and alpha-to-coverage ones were separate to begin with...)
>
> OK, I'll post my patch for review after I figure out the magic
> incantation needed in all.py to pass the --alpha-to-one flag to the
> test.  I'm nearly at my wits end here.  I may need Dylan to help me.
>

Dylan,

I'm trying to modify this block (or add a similar block) at line 3047 of 
all.py:

         for buffer_type in ('color', 'depth'):
             g(['ext_framebuffer_multisample-sample-alpha-to-coverage',
                sample_count, buffer_type],
               'sample-alpha-to-coverage {} {}'.format(
                   sample_count, buffer_type))

to pass the new --alpha-to-one argument to the test.  How do I do that? 
  I've tried about a dozen things without luck so far.

Honestly, the syntax for specifying tests in all.py seem more 
complicated than it should be.

-Brian



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