[Piglit] [PATCH 2/2] More comprehensive test for alpha blending with multisampling.
Paul Berry
stereotype441 at gmail.com
Mon Nov 4 18:27:12 PST 2013
This test validates a corner case of the fix for
https://bugs.freedesktop.org/show_bug.cgi?id=53077 ([IVB] Output error
with msaa when both of framebuffer and source color's alpha are not
1). Specifically, it verifies that the first time alpha blending is
used on a multisampled framebuffer, the contents of the framebuffer
are properly preserved.
---
tests/all.tests | 1 +
.../ext_framebuffer_multisample/CMakeLists.gl.txt | 2 +
.../alpha-blending-after-rendering.c | 203 +++++++++++++++++++++
3 files changed, 206 insertions(+)
create mode 100644 tests/spec/ext_framebuffer_multisample/alpha-blending-after-rendering.c
diff --git a/tests/all.tests b/tests/all.tests
index 43394a2..81f6a85 100644
--- a/tests/all.tests
+++ b/tests/all.tests
@@ -1775,6 +1775,7 @@ ext_framebuffer_multisample['renderbuffer-samples'] = concurrent_test('ext_frame
ext_framebuffer_multisample['samples'] = concurrent_test('ext_framebuffer_multisample-samples')
ext_framebuffer_multisample['alpha-blending'] = PlainExecTest('ext_framebuffer_multisample-alpha-blending -auto')
ext_framebuffer_multisample['alpha-blending slow_cc'] = PlainExecTest('ext_framebuffer_multisample-alpha-blending slow_cc -auto')
+ext_framebuffer_multisample['alpha-blending-after-rendering'] = PlainExecTest('ext_framebuffer_multisample-alpha-blending-after-rendering -auto')
for num_samples in MSAA_SAMPLE_COUNTS:
for test_type in ('color', 'srgb', 'stencil_draw', 'stencil_resolve',
diff --git a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
index 7f7958f..bb2ebac 100644
--- a/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
+++ b/tests/spec/ext_framebuffer_multisample/CMakeLists.gl.txt
@@ -17,6 +17,8 @@ piglit_add_executable (ext_framebuffer_multisample-alpha-to-coverage-dual-src-bl
piglit_add_executable (ext_framebuffer_multisample-alpha-to-one-dual-src-blend common.cpp
draw-buffers-common.cpp alpha-to-one-dual-src-blend.cpp)
piglit_add_executable (ext_framebuffer_multisample-alpha-blending alpha-blending.c)
+piglit_add_executable (ext_framebuffer_multisample-alpha-blending-after-rendering
+ alpha-blending-after-rendering.c)
piglit_add_executable (ext_framebuffer_multisample-alpha-to-one-msaa-disabled common.cpp
draw-buffers-common.cpp alpha-to-one-msaa-disabled.cpp)
piglit_add_executable (ext_framebuffer_multisample-alpha-to-one-single-sample-buffer common.cpp
diff --git a/tests/spec/ext_framebuffer_multisample/alpha-blending-after-rendering.c b/tests/spec/ext_framebuffer_multisample/alpha-blending-after-rendering.c
new file mode 100644
index 0000000..8c7c4ee
--- /dev/null
+++ b/tests/spec/ext_framebuffer_multisample/alpha-blending-after-rendering.c
@@ -0,0 +1,203 @@
+/*
+ * Copyright © 2013 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.
+ */
+
+/** \file
+ *
+ * Verify that alpha blending works properly in multisample
+ * framebuffers even if it is preceded by normal (non-blended)
+ * rendering.
+ *
+ * In the fix for https://bugs.freedesktop.org/show_bug.cgi?id=53077,
+ * Mesa's i965 driver must convert a compressed multisampled buffer to
+ * an uncompressed buffer the first time it notices that alpha
+ * blending is being performed on the buffer. This test verifies that
+ * the conversion happens correctly. It specifically exercises pixels
+ * that are in the following states at the time of conversion:
+ *
+ * - Clear
+ * - Fully covered
+ * - Partially covered, partially clear
+ * - Partially covered by one color, partially by another color
+ */
+
+#include "piglit-util-gl-common.h"
+
+PIGLIT_GL_TEST_CONFIG_BEGIN
+
+ config.supports_gl_compat_version = 30;
+ config.supports_gl_core_version = 31;
+ config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
+
+PIGLIT_GL_TEST_CONFIG_END
+
+const char *vs_text =
+ "#version 130\n"
+ "in vec4 piglit_vertex;\n"
+ "void main()\n"
+ "{\n"
+ " gl_Position = piglit_vertex;\n"
+ "}\n";
+
+const char *fs_text =
+ "#version 130\n"
+ "uniform vec4 color;\n"
+ "void main()\n"
+ "{\n"
+ " gl_FragColor = color;\n"
+ "}\n";
+
+static GLuint prog, singlesampled_fbo;
+static GLint color_loc;
+
+
+void
+piglit_init(int argc, char **argv)
+{
+ GLuint rb;
+
+ prog = piglit_build_simple_program(vs_text, fs_text);
+ color_loc = glGetUniformLocation(prog, "color");
+
+ /* Create the single-sampled fbo. We only need to create this
+ * once, since it isn't subject to the bugfix.
+ */
+ glGenFramebuffers(1, &singlesampled_fbo);
+ glGenRenderbuffers(1, &rb);
+ glBindFramebuffer(GL_DRAW_FRAMEBUFFER, singlesampled_fbo);
+ glBindRenderbuffer(GL_RENDERBUFFER, rb);
+ glRenderbufferStorageMultisample(GL_RENDERBUFFER,
+ 0 /* samples */,
+ GL_RGBA8 /* internalformat */,
+ piglit_width, piglit_height);
+ glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+ GL_RENDERBUFFER, rb);
+ if (glCheckFramebufferStatus(GL_DRAW_FRAMEBUFFER)
+ != GL_FRAMEBUFFER_COMPLETE) {
+ printf("Single-sampled framebuffer incomplete\n");
+ piglit_report_result(PIGLIT_FAIL);
+ }
+}
+
+
+enum piglit_result
+piglit_display(void)
+{
+ GLuint msaa_fbo, rb;
+ bool pass = true;
+ GLfloat expected_ul[] = { 0.25, 0.0, 0.25, 0.75 };
+ GLfloat expected_ur[] = { 0.0, 0.25, 0.25, 0.75 };
+ GLfloat expected_ll[] = { 0.5, 0.0, 0.0, 0.75 };
+ GLfloat expected_lr[] = { 0.0, 0.5, 0.0, 0.75 };
+
+ /* Create a multisampled framebuffer. We need to do this here
+ * (rather than in piglit_init()) because the bugfix we are
+ * verifying only converts any given buffer once; we want to
+ * make sure we trigger the bugfix for every call to
+ * piglit_display().
+ */
+ glGenFramebuffers(1, &msaa_fbo);
+ glGenRenderbuffers(1, &rb);
+ glBindFramebuffer(GL_DRAW_FRAMEBUFFER, msaa_fbo);
+ glBindRenderbuffer(GL_RENDERBUFFER, rb);
+ glRenderbufferStorageMultisample(GL_RENDERBUFFER,
+ 4 /* samples */,
+ GL_RGBA8 /* internalformat */,
+ piglit_width, piglit_height);
+ glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
+ GL_RENDERBUFFER, rb);
+ if (glCheckFramebufferStatus(GL_DRAW_FRAMEBUFFER)
+ != GL_FRAMEBUFFER_COMPLETE) {
+ printf("MSAA framebuffer incomplete\n");
+ pass = false;
+ }
+
+ /* Clear the framebuffer to red. */
+ glClearColor(1, 0, 0, 1);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ /* Paint the right half of the framebuffer green. */
+ glUseProgram(prog);
+ glDisable(GL_SAMPLE_COVERAGE);
+ glDisable(GL_BLEND);
+ glUniform4f(color_loc, 0, 1, 0, 1);
+ piglit_draw_rect(0, -1, 1, 2);
+
+ /* Paint the top half of the framebuffer blue, using 50%
+ * sample coverage.
+ */
+ glEnable(GL_SAMPLE_COVERAGE);
+ glSampleCoverage(0.5, GL_FALSE);
+ glUniform4f(color_loc, 0, 0, 1, 1);
+ piglit_draw_rect(-1, 0, 2, 1);
+
+ /* Paint black over the entire framebuffer, using 50% alpha
+ * blending.
+ */
+ glDisable(GL_SAMPLE_COVERAGE);
+ glEnable(GL_BLEND);
+ glBlendEquation(GL_FUNC_ADD);
+ glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+ glUniform4f(color_loc, 0, 0, 0, 0.5);
+ piglit_draw_rect(-1, -1, 2, 2);
+
+ /* Blit to the single-sampled fbo to force a multisample
+ * resolve. Note that we don't blit directly to the screen
+ * because the screen may be using SRGB, which might trigger
+ * the driver to do something other than linear averaging when
+ * resolving the samples.
+ */
+ glBindFramebuffer(GL_READ_FRAMEBUFFER, msaa_fbo);
+ glBindFramebuffer(GL_DRAW_FRAMEBUFFER, singlesampled_fbo);
+ glBlitFramebuffer(0, 0, piglit_width, piglit_height,
+ 0, 0, piglit_width, piglit_height,
+ GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+ /* Blit to the screen for ease in diagnosing failures. */
+ glBindFramebuffer(GL_READ_FRAMEBUFFER, singlesampled_fbo);
+ glBindFramebuffer(GL_DRAW_FRAMEBUFFER, piglit_winsys_fbo);
+ glBlitFramebuffer(0, 0, piglit_width, piglit_height,
+ 0, 0, piglit_width, piglit_height,
+ GL_COLOR_BUFFER_BIT, GL_NEAREST);
+
+ /* Check that the color is correct in each quadrant. */
+ pass = piglit_probe_rect_rgba(0, 0, piglit_width / 2,
+ piglit_height / 2, expected_ll) && pass;
+ pass = piglit_probe_rect_rgba(piglit_width - piglit_width / 2, 0,
+ piglit_width / 2, piglit_height / 2,
+ expected_lr) && pass;
+ pass = piglit_probe_rect_rgba(0, piglit_height - piglit_height / 2,
+ piglit_width / 2, piglit_height / 2,
+ expected_ul) && pass;
+ pass = piglit_probe_rect_rgba(piglit_width - piglit_width / 2,
+ piglit_height - piglit_height / 2,
+ piglit_width / 2, piglit_height / 2,
+ expected_ur) && pass;
+
+ piglit_present_results();
+
+ /* Clean up */
+ glDeleteRenderbuffers(1, &rb);
+ glDeleteFramebuffers(1, &msaa_fbo);
+
+ return pass ? PIGLIT_PASS : PIGLIT_FAIL;
+}
--
1.8.4.2
More information about the Piglit
mailing list