Fix #106312: Workbench: Texture interpolation is shared across material

This was caused by the Material Sub pass being
shared for all materials using a same texture.
This patch simply adds the sampler state inside the
Map key. This will create one unique subpass for each
texture and for each sampler state.

Pull Request: https://projects.blender.org/blender/blender/pulls/141978

source/blender/draw/engines/workbench/workbench_mesh_passes.cc

@@ -95,7 +95,7 @@ PassMain::Sub &MeshPass::get_subpass(eGeometryType geometry_type,
     };
 
     return *texture_subpass_map_.lookup_or_add_cb(
-        TextureSubPassKey(*texture->gpu.texture, geometry_type), add_cb);
+        {*texture->gpu.texture, texture->sampler_state, geometry_type}, add_cb);
   }
 
   return get_subpass(geometry_type, eShaderType::MATERIAL);

source/blender/draw/engines/workbench/workbench_private.hh

@@ -278,7 +278,22 @@ struct SceneResources {
 
 class MeshPass : public PassMain {
  private:
-  using TextureSubPassKey = std::pair<GPUTexture *, eGeometryType>;
+  struct TextureSubPassKey {
+    GPUTexture *texture;
+    GPUSamplerState sampler_state;
+    eGeometryType geom_type;
+
+    uint64_t hash() const
+    {
+      return get_default_hash(texture, sampler_state.as_uint(), geom_type);
+    }
+
+    bool operator==(TextureSubPassKey const &rhs) const
+    {
+      return this->texture == rhs.texture && this->sampler_state == rhs.sampler_state &&
+             this->geom_type == rhs.geom_type;
+    }
+  };
 
   Map<TextureSubPassKey, PassMain::Sub *> texture_subpass_map_;
 

source/blender/gpu/GPU_texture.hh

@@ -623,6 +623,16 @@ struct GPUSamplerState {
     return serialized_parameters;
   }
 
+  uint32_t as_uint() const
+  {
+    uint32_t value = filtering;
+    value = (value << 4) | extend_x;
+    value = (value << 4) | extend_yz;
+    value = (value << 8) | custom_type;
+    value = (value << 8) | type;
+    return value;
+  }
+
   bool operator==(GPUSamplerState const &rhs) const
   {
     return this->filtering == rhs.filtering && this->extend_x == rhs.extend_x &&