the ssr-history texture is not an array

the descriptor used for SSR is different depending on the pass. In
the color pass, it's used as the source of the SSRs buffers and is an
array (refraction & reflection). In the SSR pass it's the history
buffer and is just a 2D texture.

filament/src/details/MaterialInstance.cpp

@@ -284,11 +284,13 @@ void FMaterialInstance::setParameterImpl(std::string_view const name,
         auto const& descriptorSetLayout = mMaterial->getDescriptorSetLayout();
         DescriptorType const descriptorType = descriptorSetLayout.getDescriptorType(binding);
         TextureType const textureType = texture->getTextureType();
+        SamplerType const samplerType = texture->getTarget();
 
         FILAMENT_CHECK_PRECONDITION(
-                DescriptorSet::isTextureCompatibleWithDescriptor(textureType, descriptorType))
+                DescriptorSet::isTextureCompatibleWithDescriptor(textureType, samplerType, descriptorType))
                 << "Texture format " << int(texture->getFormat())
                 << " of type " << to_string(textureType)
+                << " with sampler type " << to_string(samplerType)
                 << " is not compatible with material \"" << getMaterial()->getName().c_str() << "\""
                 << " parameter \"" << name << "\""
                 << " of type " << to_string(descriptorType);

filament/src/ds/ColorPassDescriptorSet.cpp

@@ -345,25 +345,6 @@ void ColorPassDescriptorSet::prepareSSR(Handle<HwTexture> ssr,
     s.ssrDistance = (ssrOptions.enabled && !disableSSR) ? ssrOptions.maxDistance : 0.0f;
 }
 
-void ColorPassDescriptorSet::prepareHistorySSR(Handle<HwTexture> ssr,
-        mat4f const& historyProjection,
-        mat4f const& uvFromViewMatrix,
-        ScreenSpaceReflectionsOptions const& ssrOptions) noexcept {
-
-    setSampler(+PerViewBindingPoints::SSR, ssr, {
-        .filterMag = SamplerMagFilter::LINEAR,
-        .filterMin = SamplerMinFilter::LINEAR
-    });
-
-    auto& s = mUniforms.edit();
-    s.ssrReprojection = historyProjection;
-    s.ssrUvFromViewMatrix = uvFromViewMatrix;
-    s.ssrThickness = ssrOptions.thickness;
-    s.ssrBias = ssrOptions.bias;
-    s.ssrDistance = ssrOptions.enabled ? ssrOptions.maxDistance : 0.0f;
-    s.ssrStride = ssrOptions.stride;
-}
-
 void ColorPassDescriptorSet::prepareStructure(Handle<HwTexture> structure) noexcept {
     // sampler must be NEAREST
     setSampler(+PerViewBindingPoints::STRUCTURE, structure, {});

filament/src/ds/ColorPassDescriptorSet.h

@@ -117,11 +117,6 @@ public:
             float refractionLodOffset,
             ScreenSpaceReflectionsOptions const& ssrOptions) noexcept;
 
-    void prepareHistorySSR(TextureHandle ssr,
-            math::mat4f const& historyProjection,
-            math::mat4f const& uvFromViewMatrix,
-            ScreenSpaceReflectionsOptions const& ssrOptions) noexcept;
-
     void prepareShadowMapping(backend::BufferObjectHandle shadowUniforms, bool highPrecision) noexcept;
 
     void prepareDirectionalLight(FEngine& engine, float exposure,

filament/src/ds/DescriptorSet.cpp

@@ -198,9 +198,40 @@ DescriptorSet DescriptorSet::duplicate(
     return set;
 }
 bool DescriptorSet::isTextureCompatibleWithDescriptor(
-    backend::TextureType t, backend::DescriptorType d) noexcept {
+    backend::TextureType t, backend::SamplerType s, backend::DescriptorType d) noexcept {
     using namespace backend;
 
+    switch (s) {
+        case SamplerType::SAMPLER_2D:
+            if (!is2dTypeDescriptor(d)) {
+                return false;
+            }
+            break;
+        case SamplerType::SAMPLER_2D_ARRAY:
+            if (!is2dArrayTypeDescriptor(d)) {
+                return false;
+            }
+            break;
+        case SamplerType::SAMPLER_CUBEMAP:
+            if (!isCubeTypeDescriptor(d)) {
+                return false;
+            }
+            break;
+        case SamplerType::SAMPLER_CUBEMAP_ARRAY:
+            if (!isCubeArrayTypeDescriptor(d)) {
+                return false;
+            }
+            break;
+        case SamplerType::SAMPLER_3D:
+            if (!is3dTypeDescriptor(d)) {
+                return false;
+            }
+            break;
+        case SamplerType::SAMPLER_EXTERNAL:
+            break;
+    }
+
+    // check that the descriptor type is compatible with the texture format type
     switch (d) {
         case DescriptorType::SAMPLER_2D_FLOAT:
         case DescriptorType::SAMPLER_2D_ARRAY_FLOAT:

filament/src/ds/DescriptorSet.h

@@ -86,7 +86,8 @@ public:
     }
 
     static bool isTextureCompatibleWithDescriptor(
-        backend::TextureType t, backend::DescriptorType d) noexcept;
+            backend::TextureType t, backend::SamplerType s,
+            backend::DescriptorType d) noexcept;
 
 private:
     struct Desc {

filament/src/ds/SsrPassDescriptorSet.cpp

@@ -76,7 +76,7 @@ void SsrPassDescriptorSet::prepareHistorySSR(FEngine const& engine, Handle<HwTex
         ScreenSpaceReflectionsOptions const& ssrOptions) noexcept {
 
     mDescriptorSet.setSampler(engine.getPerViewDescriptorSetLayoutSsrVariant(),
-            +PerViewBindingPoints::SSR, ssr, {
+            +PerViewBindingPoints::SSR_HISTORY, ssr, {
                 .filterMag = SamplerMagFilter::LINEAR,
                 .filterMin = SamplerMinFilter::LINEAR
             });

libs/filabridge/include/private/filament/EngineEnums.h

@@ -54,7 +54,8 @@ enum class PerViewBindingPoints : uint8_t  {
     IBL_DFG_LUT     =  7,   // user defined (128x128), RGB16F
     IBL_SPECULAR    =  8,   // user defined, user defined, CUBEMAP
     SSAO            =  9,   // variable, RGB8 {AO, [depth]}
-    SSR             = 10,   // variable, RGB_11_11_10, mipmapped
+    SSR             = 10,   // variable, 2d array, RGB_11_11_10, mipmapped
+    SSR_HISTORY     = 10,   // variable, 2d texture, RGB_11_11_10
     FOG             = 11    // variable, user defined, CUBEMAP
 };
 

libs/filabridge/src/DescriptorSets.cpp

@@ -59,7 +59,7 @@ static constexpr std::initializer_list<DescriptorSetLayoutBinding> ssrVariantDes
     { DescriptorType::UNIFORM_BUFFER, ShaderStageFlags::VERTEX | ShaderStageFlags::FRAGMENT,  +PerViewBindingPoints::FRAME_UNIFORMS },
     { DescriptorType::UNIFORM_BUFFER, ShaderStageFlags::VERTEX | ShaderStageFlags::FRAGMENT,  +PerViewBindingPoints::SHADOWS        },
     { DescriptorType::SAMPLER_2D_FLOAT,                          ShaderStageFlags::FRAGMENT,  +PerViewBindingPoints::STRUCTURE, DescriptorFlags::UNFILTERABLE },
-    { DescriptorType::SAMPLER_2D_ARRAY_FLOAT,                    ShaderStageFlags::FRAGMENT,  +PerViewBindingPoints::SSR            },
+    { DescriptorType::SAMPLER_2D_FLOAT,                          ShaderStageFlags::FRAGMENT,  +PerViewBindingPoints::SSR_HISTORY    },
 };
 
 // Used for generating the color pass (i.e. the main pass). This is in fact a template that gets