Add wgpu::TextureComponentType::DepthComparison

And deprecate using ::Float in the bind group layout for
"shadow textures" in the pipeline (along with a deprecation test).

Adds the ability to be used with DepthComparison only to depth textures,
this could potentially a breaking change if users where doing
depth-comparison on float32 textures but that's not supported in WebGPU.

Bug: dawn:527
Change-Id: Ib28b0443e3002e0aa2811713b9e843c2417e13e7
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/30240
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Stephen White <senorblanco@chromium.org>

src/tests/end2end/DeprecatedAPITests.cpp

@@ -118,6 +118,50 @@ TEST_P(DeprecationTests, BGLEntryMultisampledBooleanTracking) {
     utils::MakeBindGroup(device, bgl, {{0, texture4Sample.CreateView()}});
 }
 
+// Test that compiling a pipeline with TextureComponentType::Float in the BGL when ::DepthComparison
+// is expected emits a deprecation warning but isn't an error.
+TEST_P(DeprecationTests, TextureComponentTypeFloatWhenDepthComparisonIsExpected) {
+    wgpu::ShaderModule module =
+        utils::CreateShaderModule(device, utils::SingleShaderStage::Compute, R"(
+            #version 450
+            layout(set = 0, binding = 0) uniform samplerShadow samp;
+            layout(set = 0, binding = 1) uniform texture2D tex;
+
+            void main() {
+                texture(sampler2DShadow(tex, samp), vec3(0.5, 0.5, 0.5));
+            }
+        )");
+
+    {
+        wgpu::BindGroupLayout goodBgl = utils::MakeBindGroupLayout(
+            device,
+            {{0, wgpu::ShaderStage::Compute, wgpu::BindingType::ComparisonSampler},
+             {1, wgpu::ShaderStage::Compute, wgpu::BindingType::SampledTexture, false, 0, false,
+              wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison}});
+
+        wgpu::ComputePipelineDescriptor goodDesc;
+        goodDesc.layout = utils::MakeBasicPipelineLayout(device, &goodBgl);
+        goodDesc.computeStage.module = module;
+        goodDesc.computeStage.entryPoint = "main";
+
+        device.CreateComputePipeline(&goodDesc);
+    }
+
+    {
+        wgpu::BindGroupLayout badBgl = utils::MakeBindGroupLayout(
+            device, {{0, wgpu::ShaderStage::Compute, wgpu::BindingType::ComparisonSampler},
+                     {1, wgpu::ShaderStage::Compute, wgpu::BindingType::SampledTexture, false, 0,
+                      false, wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::Float}});
+
+        wgpu::ComputePipelineDescriptor badDesc;
+        badDesc.layout = utils::MakeBasicPipelineLayout(device, &badBgl);
+        badDesc.computeStage.module = module;
+        badDesc.computeStage.entryPoint = "main";
+
+        EXPECT_DEPRECATION_WARNING(device.CreateComputePipeline(&badDesc));
+    }
+}
+
 DAWN_INSTANTIATE_TEST(DeprecationTests,
                       D3D12Backend(),
                       MetalBackend(),

src/tests/end2end/DepthSamplingTests.cpp

@@ -151,9 +151,11 @@ class DepthSamplingTest : public DawnTest {
         // TODO(dawn:367): Cannot use GetBindGroupLayout for comparison samplers without shader
         // reflection data.
         wgpu::BindGroupLayout bgl = utils::MakeBindGroupLayout(
-            device, {{0, wgpu::ShaderStage::Fragment, wgpu::BindingType::ComparisonSampler},
-                     {1, wgpu::ShaderStage::Fragment, wgpu::BindingType::SampledTexture},
-                     {2, wgpu::ShaderStage::Fragment, wgpu::BindingType::UniformBuffer}});
+            device,
+            {{0, wgpu::ShaderStage::Fragment, wgpu::BindingType::ComparisonSampler},
+             {1, wgpu::ShaderStage::Fragment, wgpu::BindingType::SampledTexture, false, 0, false,
+              wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison},
+             {2, wgpu::ShaderStage::Fragment, wgpu::BindingType::UniformBuffer}});
 
         utils::ComboRenderPipelineDescriptor pipelineDescriptor(device);
         pipelineDescriptor.vertexStage.module = vsModule;
@@ -185,10 +187,12 @@ class DepthSamplingTest : public DawnTest {
 
         // TODO(dawn:367): Cannot use GetBindGroupLayout without shader reflection data.
         wgpu::BindGroupLayout bgl = utils::MakeBindGroupLayout(
-            device, {{0, wgpu::ShaderStage::Compute, wgpu::BindingType::ComparisonSampler},
-                     {1, wgpu::ShaderStage::Compute, wgpu::BindingType::SampledTexture},
-                     {2, wgpu::ShaderStage::Compute, wgpu::BindingType::UniformBuffer},
-                     {3, wgpu::ShaderStage::Compute, wgpu::BindingType::StorageBuffer}});
+            device,
+            {{0, wgpu::ShaderStage::Compute, wgpu::BindingType::ComparisonSampler},
+             {1, wgpu::ShaderStage::Compute, wgpu::BindingType::SampledTexture, false, 0, false,
+              wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison},
+             {2, wgpu::ShaderStage::Compute, wgpu::BindingType::UniformBuffer},
+             {3, wgpu::ShaderStage::Compute, wgpu::BindingType::StorageBuffer}});
 
         wgpu::ComputePipelineDescriptor pipelineDescriptor;
         pipelineDescriptor.layout = utils::MakeBasicPipelineLayout(device, &bgl);

src/tests/unittests/validation/BindGroupValidationTests.cpp

@@ -345,6 +345,41 @@ TEST_F(BindGroupValidationTest, SamplingDepthTexture) {
     }
 }
 
+// Check that a texture must have a correct format for DepthComparison
+TEST_F(BindGroupValidationTest, TextureComponentTypeDepthComparison) {
+    wgpu::BindGroupLayout depthLayout = utils::MakeBindGroupLayout(
+        device,
+        {{0, wgpu::ShaderStage::Fragment, wgpu::BindingType::SampledTexture, false, 0, false,
+          wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison}});
+
+    // Control case: setting a depth texture works.
+    wgpu::Texture depthTexture =
+        CreateTexture(wgpu::TextureUsage::Sampled, wgpu::TextureFormat::Depth32Float, 1);
+    utils::MakeBindGroup(device, depthLayout, {{0, depthTexture.CreateView()}});
+
+    // Error case: setting a Float typed texture view fails.
+    ASSERT_DEVICE_ERROR(utils::MakeBindGroup(device, depthLayout, {{0, mSampledTextureView}}));
+}
+
+// Check that a depth texture is allowed to be used for both TextureComponentType::Float and
+// ::DepthComparison
+TEST_F(BindGroupValidationTest, TextureComponentTypeForDepthTexture) {
+    wgpu::BindGroupLayout depthLayout = utils::MakeBindGroupLayout(
+        device,
+        {{0, wgpu::ShaderStage::Fragment, wgpu::BindingType::SampledTexture, false, 0, false,
+          wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison}});
+
+    wgpu::BindGroupLayout floatLayout = utils::MakeBindGroupLayout(
+        device, {{0, wgpu::ShaderStage::Fragment, wgpu::BindingType::SampledTexture, false, 0,
+                  false, wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::Float}});
+
+    wgpu::Texture depthTexture =
+        CreateTexture(wgpu::TextureUsage::Sampled, wgpu::TextureFormat::Depth32Float, 1);
+
+    utils::MakeBindGroup(device, depthLayout, {{0, depthTexture.CreateView()}});
+    utils::MakeBindGroup(device, floatLayout, {{0, depthTexture.CreateView()}});
+}
+
 // Check that a texture must have the correct dimension
 TEST_F(BindGroupValidationTest, TextureDimension) {
     wgpu::BindGroupLayout layout = utils::MakeBindGroupLayout(
@@ -900,7 +935,7 @@ TEST_F(BindGroupLayoutValidationTest, DynamicBufferNumberLimit) {
 }
 
 // Test that multisampled textures must be 2D sampled textures
-TEST_F(BindGroupLayoutValidationTest, MultisampledTextures) {
+TEST_F(BindGroupLayoutValidationTest, MultisampledTextureViewDimension) {
     // Multisampled 2D texture works.
     utils::MakeBindGroupLayout(
         device, {
@@ -958,6 +993,45 @@ TEST_F(BindGroupLayoutValidationTest, MultisampledTextures) {
                 }));
 }
 
+// Test that multisampled textures cannot be DepthComparison
+TEST_F(BindGroupLayoutValidationTest, MultisampledTextureComponentType) {
+    // Multisampled float component type works.
+    utils::MakeBindGroupLayout(
+        device, {
+                    {0, wgpu::ShaderStage::Compute, wgpu::BindingType::MultisampledTexture, false,
+                     0, false, wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::Float},
+                });
+
+    // Multisampled float (defaulted) component type works.
+    utils::MakeBindGroupLayout(
+        device, {
+                    {0, wgpu::ShaderStage::Compute, wgpu::BindingType::MultisampledTexture, false,
+                     0, false, wgpu::TextureViewDimension::e2D},
+                });
+
+    // Multisampled uint component type works.
+    utils::MakeBindGroupLayout(
+        device, {
+                    {0, wgpu::ShaderStage::Compute, wgpu::BindingType::MultisampledTexture, false,
+                     0, false, wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::Uint},
+                });
+
+    // Multisampled sint component type works.
+    utils::MakeBindGroupLayout(
+        device, {
+                    {0, wgpu::ShaderStage::Compute, wgpu::BindingType::MultisampledTexture, false,
+                     0, false, wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::Sint},
+                });
+
+    // Multisampled depth comparison component typeworks.
+    ASSERT_DEVICE_ERROR(utils::MakeBindGroupLayout(
+        device,
+        {
+            {0, wgpu::ShaderStage::Compute, wgpu::BindingType::MultisampledTexture, false, 0, false,
+             wgpu::TextureViewDimension::e2D, wgpu::TextureComponentType::DepthComparison},
+        }));
+}
+
 // Test that it is an error to pass multisampled=true for non-texture bindings
 TEST_F(BindGroupLayoutValidationTest, MultisampledMustBeTexture) {
     // Base: Multisampled 2D texture works.