Fix multisample renderbuffer compliance (e.g. 3->4 samples)

src/libANGLE/Renderbuffer.cpp

@@ -114,14 +114,11 @@ angle::Result Renderbuffer::setStorageMultisample(const Context *context,
                                                   size_t height)
 {
     ANGLE_TRY(orphanImages(context));
-    // TODO (ianelliott): Ensure that the following spec language is correctly implemented:
-    //
-    //   the resulting value for RENDERBUFFER_SAMPLES is guaranteed to be greater than or equal to
-    //   samples and no more than the next larger sample count supported by the implementation.
-    //
-    // For example, if 2, 4, and 8 samples are supported, and if 5 samples are requested, ANGLE
-    // should use 8 samples, and return 8 when GL_RENDERBUFFER_SAMPLES is queried.
-    // http://anglebug.com/4196
+
+    // Potentially adjust "samples" to a supported value
+    const TextureCaps &formatCaps = context->getTextureCaps().get(internalformat);
+    samples                       = formatCaps.getNearestSamples(static_cast<GLuint>(samples));
+
     ANGLE_TRY(
         mImplementation->setStorageMultisample(context, samples, internalformat, width, height));
 

src/libANGLE/renderer/renderer_utils.cpp

@@ -803,6 +803,7 @@ void OverrideFeaturesWithDisplayState(angle::FeatureSetBase *features,
 
 void GetSamplePosition(GLsizei sampleCount, size_t index, GLfloat *xy)
 {
+    ASSERT(gl::isPow2(sampleCount));
     if (sampleCount > 16)
     {
         // Vulkan (and D3D11) doesn't have standard sample positions for 32 and 64 samples (and no

src/libANGLE/renderer/vulkan/RenderbufferVk.cpp

@@ -101,36 +101,6 @@ angle::Result RenderbufferVk::setStorageMultisample(const gl::Context *context,
                                                     size_t width,
                                                     size_t height)
 {
-    // If the specific number of samples requested is not supported, the smallest number that's at
-    // least that many needs to be selected.
-    const RendererVk *renderer           = vk::GetImpl(context)->getRenderer();
-    const angle::Format &format          = renderer->getFormat(internalformat).actualImageFormat();
-    const VkPhysicalDeviceLimits &limits = renderer->getPhysicalDeviceProperties().limits;
-
-    const uint32_t colorSampleCounts        = limits.framebufferColorSampleCounts;
-    const uint32_t depthSampleCounts        = limits.framebufferDepthSampleCounts;
-    const uint32_t stencilSampleCounts      = limits.framebufferStencilSampleCounts;
-    const uint32_t depthStencilSampleCounts = depthSampleCounts & stencilSampleCounts;
-    uint32_t formatSampleCounts             = colorSampleCounts;
-
-    if (format.depthBits > 0)
-    {
-        if (format.stencilBits > 0)
-        {
-            formatSampleCounts = depthStencilSampleCounts;
-        }
-        else
-        {
-            formatSampleCounts = depthSampleCounts;
-        }
-    }
-    else if (format.stencilBits > 0)
-    {
-        formatSampleCounts = stencilSampleCounts;
-    }
-
-    samples = vk_gl::GetSampleCount(formatSampleCounts, static_cast<uint32_t>(samples));
-
     return setStorageImpl(context, samples, internalformat, width, height);
 }
 

src/tests/deqp_support/deqp_gles3_test_expectations.txt

@@ -527,6 +527,7 @@
 
 // Fails on Windows + Linux.
 2222 OPENGL NVIDIA : dEQP-GLES3.functional.fbo.completeness.samples.rbo2_rbo2_rbo0 = FAIL
+2222 OPENGL NVIDIA : dEQP-GLES3.functional.fbo.completeness.samples.rbo1_rbo2_rbo0 = FAIL
 
 // General Vulkan failures
 

src/tests/gl_tests/RenderbufferMultisampleTest.cpp

@@ -114,9 +114,7 @@ TEST_P(RenderbufferMultisampleTest, OddSampleCount)
             glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_SAMPLES,
                                          &renderbufferSamples);
             ASSERT_GL_NO_ERROR();
-            // TODO (ianelliott): Uncomment the following line once the implementation is fixed.
-            // http://anglebug.com/4196
-            // EXPECT_EQ(renderbufferSamples, sampleCounts[i-1]);
+            EXPECT_EQ(renderbufferSamples, sampleCounts[i - 1]);
             break;
         }
     }