Vulkan: Add features to modify sampling parameters

include/platform/FeaturesVk.h

@@ -11,6 +11,8 @@
 
 #include "platform/Feature.h"
 
+#include <array>
+
 namespace angle
 {
 
@@ -378,6 +380,34 @@ struct FeaturesVk : FeatureSetBase
         "Before passing an oldSwapchain to VkSwapchainCreateInfoKHR, wait for queue to be idle. "
         "Works around a bug on platforms which destroy oldSwapchain in vkCreateSwapchainKHR.",
         &members, "http://anglebug.com/5061"};
+
+    // Allow forcing an LOD offset on all sampling operations for performance comparisons. ANGLE is
+    // non-conformant if this feature is enabled.
+    std::array<angle::Feature, 4> forceTextureLODOffset = {
+        angle::Feature{"force_texture_lod_offset_1", angle::FeatureCategory::VulkanWorkarounds,
+                       "Increase the minimum texture level-of-detail by 1 when sampling.",
+                       &members},
+        angle::Feature{"force_texture_lod_offset_2", angle::FeatureCategory::VulkanWorkarounds,
+                       "Increase the minimum texture level-of-detail by 2 when sampling.",
+                       &members},
+        angle::Feature{"force_texture_lod_offset_3", angle::FeatureCategory::VulkanWorkarounds,
+                       "Increase the minimum texture level-of-detail by 3 when sampling.",
+                       &members},
+        angle::Feature{"force_texture_lod_offset_4", angle::FeatureCategory::VulkanWorkarounds,
+                       "Increase the minimum texture level-of-detail by 4 when sampling.",
+                       &members},
+    };
+
+    // Translate non-nearest filtering modes to nearest for all samplers for performance
+    // comparisons. ANGLE is non-conformant if this feature is enabled.
+    Feature forceNearestFiltering = {"force_nearest_filtering", FeatureCategory::VulkanWorkarounds,
+                                     "Force nearest filtering when sampling.", &members};
+
+    // Translate  non-nearest mip filtering modes to nearest mip for all samplers for performance
+    // comparisons. ANGLE is non-conformant if this feature is enabled.
+    Feature forceNearestMipFiltering = {"force_nearest_mip_filtering",
+                                        FeatureCategory::VulkanWorkarounds,
+                                        "Force nearest mip filtering when sampling.", &members};
 };
 
 inline FeaturesVk::FeaturesVk()  = default;

src/libANGLE/Texture.cpp

@@ -67,6 +67,34 @@ bool IsMipmapFiltered(GLenum minFilterMode)
     }
 }
 
+GLenum ConvertToNearestFilterMode(GLenum filterMode)
+{
+    switch (filterMode)
+    {
+        case GL_LINEAR:
+            return GL_NEAREST;
+        case GL_LINEAR_MIPMAP_NEAREST:
+            return GL_NEAREST_MIPMAP_NEAREST;
+        case GL_LINEAR_MIPMAP_LINEAR:
+            return GL_NEAREST_MIPMAP_LINEAR;
+        default:
+            return filterMode;
+    }
+}
+
+GLenum ConvertToNearestMipFilterMode(GLenum filterMode)
+{
+    switch (filterMode)
+    {
+        case GL_LINEAR_MIPMAP_LINEAR:
+            return GL_LINEAR_MIPMAP_NEAREST;
+        case GL_NEAREST_MIPMAP_LINEAR:
+            return GL_NEAREST_MIPMAP_NEAREST;
+        default:
+            return filterMode;
+    }
+}
+
 SwizzleState::SwizzleState()
     : swizzleRed(GL_RED), swizzleGreen(GL_GREEN), swizzleBlue(GL_BLUE), swizzleAlpha(GL_ALPHA)
 {}

src/libANGLE/Texture.h

@@ -52,6 +52,12 @@ constexpr GLuint kInitialMaxLevel = 1000;
 
 bool IsMipmapFiltered(GLenum minFilterMode);
 
+// Convert a given filter mode to nearest filtering.
+GLenum ConvertToNearestFilterMode(GLenum filterMode);
+
+// Convert a given filter mode to nearest mip filtering.
+GLenum ConvertToNearestMipFilterMode(GLenum filterMode);
+
 struct ImageDesc final
 {
     ImageDesc();

src/libANGLE/renderer/vulkan/RendererVk.cpp

@@ -1884,6 +1884,14 @@ void RendererVk::initFeatures(DisplayVk *displayVk, const ExtensionNameList &dev
     // Android mistakenly destroys the old swapchain when creating a new one.
     ANGLE_FEATURE_CONDITION(&mFeatures, waitIdleBeforeSwapchainRecreation, IsAndroid() && isARM);
 
+    for (size_t lodOffsetFeatureIdx = 0;
+         lodOffsetFeatureIdx < mFeatures.forceTextureLODOffset.size(); lodOffsetFeatureIdx++)
+    {
+        ANGLE_FEATURE_CONDITION(&mFeatures, forceTextureLODOffset[lodOffsetFeatureIdx], false);
+    }
+    ANGLE_FEATURE_CONDITION(&mFeatures, forceNearestFiltering, false);
+    ANGLE_FEATURE_CONDITION(&mFeatures, forceNearestMipFiltering, false);
+
     angle::PlatformMethods *platform = ANGLEPlatformCurrent();
     platform->overrideFeaturesVk(platform, &mFeatures);
 

src/libANGLE/renderer/vulkan/SamplerVk.cpp

@@ -39,7 +39,7 @@ angle::Result SamplerVk::syncState(const gl::Context *context, const bool dirty)
         mSampler.reset();
     }
 
-    vk::SamplerDesc desc(mState, false, 0);
+    vk::SamplerDesc desc(contextVk->getFeatures(), mState, false, 0);
     ANGLE_TRY(renderer->getSamplerCache().getSampler(contextVk, desc, &mSampler));
 
     return angle::Result::Continue;

src/libANGLE/renderer/vulkan/TextureVk.cpp

@@ -1519,7 +1519,7 @@ angle::Result TextureVk::generateMipmapsWithCompute(ContextVk *contextVk)
     samplerState.setWrapR(GL_CLAMP_TO_EDGE);
 
     vk::BindingPointer<vk::SamplerHelper> sampler;
-    vk::SamplerDesc samplerDesc(samplerState, false, 0);
+    vk::SamplerDesc samplerDesc(contextVk->getFeatures(), samplerState, false, 0);
     ANGLE_TRY(renderer->getSamplerCache().getSampler(contextVk, samplerDesc, &sampler));
 
     // If the image has more levels than supported, generate as many mips as possible at a time.
@@ -2204,8 +2204,8 @@ angle::Result TextureVk::syncState(const gl::Context *context,
         onStateChange(angle::SubjectMessage::SubjectChanged);
     }
 
-    vk::SamplerDesc samplerDesc(mState.getSamplerState(), mState.isStencilMode(),
-                                mImage->getExternalFormat());
+    vk::SamplerDesc samplerDesc(contextVk->getFeatures(), mState.getSamplerState(),
+                                mState.isStencilMode(), mImage->getExternalFormat());
     ANGLE_TRY(renderer->getSamplerCache().getSampler(contextVk, samplerDesc, &mSampler));
 
     return angle::Result::Continue;

src/libANGLE/renderer/vulkan/vk_cache_utils.cpp

@@ -2248,11 +2248,12 @@ SamplerDesc::SamplerDesc(const SamplerDesc &other) = default;
 
 SamplerDesc &SamplerDesc::operator=(const SamplerDesc &rhs) = default;
 
-SamplerDesc::SamplerDesc(const gl::SamplerState &samplerState,
+SamplerDesc::SamplerDesc(const angle::FeaturesVk &featuresVk,
+                         const gl::SamplerState &samplerState,
                          bool stencilMode,
                          uint64_t externalFormat)
 {
-    update(samplerState, stencilMode, externalFormat);
+    update(featuresVk, samplerState, stencilMode, externalFormat);
 }
 
 void SamplerDesc::reset()
@@ -2275,11 +2276,23 @@ void SamplerDesc::reset()
     mReserved[2]    = 0;
 }
 
-void SamplerDesc::update(const gl::SamplerState &samplerState,
+void SamplerDesc::update(const angle::FeaturesVk &featuresVk,
+                         const gl::SamplerState &samplerState,
                          bool stencilMode,
                          uint64_t externalFormat)
 {
-    mMipLodBias    = 0.0f;
+    mMipLodBias = 0.0f;
+    for (size_t lodOffsetFeatureIdx = 0;
+         lodOffsetFeatureIdx < featuresVk.forceTextureLODOffset.size(); lodOffsetFeatureIdx++)
+    {
+        if (featuresVk.forceTextureLODOffset[lodOffsetFeatureIdx].enabled)
+        {
+            // Make sure only one forceTextureLODOffset feature is set.
+            ASSERT(mMipLodBias == 0.0f);
+            mMipLodBias = static_cast<float>(lodOffsetFeatureIdx + 1);
+        }
+    }
+
     mMaxAnisotropy = samplerState.getMaxAnisotropy();
     mMinLod        = samplerState.getMinLod();
     mMaxLod        = samplerState.getMaxLod();
@@ -2298,8 +2311,20 @@ void SamplerDesc::update(const gl::SamplerState &samplerState,
         compareOp     = VK_COMPARE_OP_ALWAYS;
     }
 
-    SetBitField(mMagFilter, gl_vk::GetFilter(samplerState.getMagFilter()));
-    SetBitField(mMinFilter, gl_vk::GetFilter(samplerState.getMinFilter()));
+    GLenum magFilter = samplerState.getMagFilter();
+    GLenum minFilter = samplerState.getMinFilter();
+    if (featuresVk.forceNearestFiltering.enabled)
+    {
+        magFilter = gl::ConvertToNearestFilterMode(magFilter);
+        minFilter = gl::ConvertToNearestFilterMode(minFilter);
+    }
+    if (featuresVk.forceNearestMipFiltering.enabled)
+    {
+        minFilter = gl::ConvertToNearestMipFilterMode(minFilter);
+    }
+
+    SetBitField(mMagFilter, gl_vk::GetFilter(magFilter));
+    SetBitField(mMinFilter, gl_vk::GetFilter(minFilter));
     SetBitField(mMipmapMode, gl_vk::GetSamplerMipmapMode(samplerState.getMinFilter()));
     SetBitField(mAddressModeU, gl_vk::GetSamplerAddressMode(samplerState.getWrapS()));
     SetBitField(mAddressModeV, gl_vk::GetSamplerAddressMode(samplerState.getWrapT()));
@@ -2307,7 +2332,7 @@ void SamplerDesc::update(const gl::SamplerState &samplerState,
     SetBitField(mCompareEnabled, compareEnable);
     SetBitField(mCompareOp, compareOp);
 
-    if (!gl::IsMipmapFiltered(samplerState.getMinFilter()))
+    if (!gl::IsMipmapFiltered(minFilter))
     {
         // Per the Vulkan spec, GL_NEAREST and GL_LINEAR do not map directly to Vulkan, so
         // they must be emulated (See "Mapping of OpenGL to Vulkan filter modes")
@@ -2336,7 +2361,7 @@ angle::Result SamplerDesc::init(ContextVk *contextVk, vk::Sampler *sampler) cons
     createInfo.addressModeU            = static_cast<VkSamplerAddressMode>(mAddressModeU);
     createInfo.addressModeV            = static_cast<VkSamplerAddressMode>(mAddressModeV);
     createInfo.addressModeW            = static_cast<VkSamplerAddressMode>(mAddressModeW);
-    createInfo.mipLodBias              = 0.0f;
+    createInfo.mipLodBias              = mMipLodBias;
     createInfo.anisotropyEnable        = anisotropyEnable;
     createInfo.maxAnisotropy           = mMaxAnisotropy;
     createInfo.compareEnable           = mCompareEnabled ? VK_TRUE : VK_FALSE;

src/libANGLE/renderer/vulkan/vk_cache_utils.h

@@ -756,13 +756,19 @@ class SamplerDesc final
 {
   public:
     SamplerDesc();
-    SamplerDesc(const gl::SamplerState &samplerState, bool stencilMode, uint64_t externalFormat);
+    SamplerDesc(const angle::FeaturesVk &featuresVk,
+                const gl::SamplerState &samplerState,
+                bool stencilMode,
+                uint64_t externalFormat);
     ~SamplerDesc();
 
     SamplerDesc(const SamplerDesc &other);
     SamplerDesc &operator=(const SamplerDesc &rhs);
 
-    void update(const gl::SamplerState &samplerState, bool stencilMode, uint64_t externalFormat);
+    void update(const angle::FeaturesVk &featuresVk,
+                const gl::SamplerState &samplerState,
+                bool stencilMode,
+                uint64_t externalFormat);
     void reset();
     angle::Result init(ContextVk *contextVk, vk::Sampler *sampler) const;