From: Roland Scheidegger <srol...@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.pho...@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;
+}
