[D3D12] SRV and sampler bindings

src/xenia/gpu/d3d12/texture_cache.h

@@ -0,0 +1,72 @@
+/**
+ ******************************************************************************
+ * Xenia : Xbox 360 Emulator Research Project                                 *
+ ******************************************************************************
+ * Copyright 2018 Ben Vanik. All rights reserved.                             *
+ * Released under the BSD license - see LICENSE in the root for more details. *
+ ******************************************************************************
+ */
+
+#ifndef XENIA_GPU_D3D12_TEXTURE_CACHE_H_
+#define XENIA_GPU_D3D12_TEXTURE_CACHE_H_
+
+#include "xenia/gpu/register_file.h"
+#include "xenia/gpu/xenos.h"
+#include "xenia/ui/d3d12/d3d12_api.h"
+
+namespace xe {
+namespace gpu {
+namespace d3d12 {
+
+class D3D12CommandProcessor;
+
+// Manages host copies of guest textures, performing untiling, format and endian
+// conversion of textures stored in the shared memory, and also handling
+// invalidation.
+//
+// Mipmaps are treated the following way, according to the GPU hang message
+// found in game executables explaining the valid usage of BaseAddress when
+// streaming the largest LOD (it says games should not use 0 as the base address
+// when the largest LOD isn't loaded, but rather, either allocate a valid
+// address for it or make it the same as MipAddress):
+// - If the texture has a base address, but no mip address, it's not mipmapped -
+//   the host texture has only the largest level too.
+// - If the texture has different non-zero base address and mip address, a host
+//   texture full mipmap pyramid is created, disregarding min/max LOD and
+//   treating it purely as sampler state because there are tfetch instructions
+//   working directly with LOD values - including fetching with an explicit LOD.
+// - If the texture has a mip address, but the base address is 0 or the same as
+//   the mip address, a fully mipmapped texture is created, but min/max LOD is
+//   clamped to 1 - the game is expected to do that anyway until the largest LOD
+//   is loaded.
+//   TODO(Triang3l): Check if there are any games with BaseAddress==MipAddress
+//   but min or max LOD being 0, especially check Modern Warfare 2/3.
+//   TODO(Triang3l): Attach the largest LOD to existing textures with a valid
+//   MipAddress but no BaseAddress to save memory because textures are streamed
+//   this way anyway.
+class TextureCache {
+ public:
+  TextureCache(D3D12CommandProcessor* command_processor,
+               RegisterFile* register_file);
+  ~TextureCache();
+
+  void Shutdown();
+
+  void ClearCache();
+
+  void WriteTextureSRV(uint32_t fetch_constant,
+                       TextureDimension shader_dimension,
+                       D3D12_CPU_DESCRIPTOR_HANDLE handle);
+  void WriteSampler(uint32_t fetch_constant,
+                    D3D12_CPU_DESCRIPTOR_HANDLE handle);
+
+ private:
+  D3D12CommandProcessor* command_processor_;
+  RegisterFile* register_file_;
+};
+
+}  // namespace d3d12
+}  // namespace gpu
+}  // namespace xe
+
+#endif  // XENIA_GPU_D3D12_TEXTURE_CACHE_H_