VideoBackends/D3D: Cache bounding box values between reads

Source/Core/VideoBackends/D3D/D3DBoundingBox.cpp

@@ -2,18 +2,25 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
-#include "VideoBackends/D3D/D3DBoundingBox.h"
+#include <algorithm>
+#include <array>
+
 #include "Common/CommonTypes.h"
 #include "Common/MsgHandler.h"
+#include "VideoBackends/D3D/D3DBoundingBox.h"
 #include "VideoBackends/D3D/D3DState.h"
 #include "VideoBackends/D3DCommon/D3DCommon.h"
 #include "VideoCommon/VideoConfig.h"
 
 namespace DX11
 {
+static constexpr u32 NUM_BBOX_VALUES = 4;
 static ComPtr<ID3D11Buffer> s_bbox_buffer;
 static ComPtr<ID3D11Buffer> s_bbox_staging_buffer;
 static ComPtr<ID3D11UnorderedAccessView> s_bbox_uav;
+static std::array<s32, NUM_BBOX_VALUES> s_bbox_values;
+static std::array<bool, NUM_BBOX_VALUES> s_bbox_dirty;
+static bool s_bbox_valid = false;
 
 ID3D11UnorderedAccessView* BBox::GetUAV()
 {
@@ -22,42 +29,45 @@ ID3D11UnorderedAccessView* BBox::GetUAV()
 
 void BBox::Init()
 {
-  if (g_ActiveConfig.backend_info.bSupportsBBox)
-  {
-    // Create 2 buffers here.
-    // First for unordered access on default pool.
-    auto desc = CD3D11_BUFFER_DESC(4 * sizeof(s32), D3D11_BIND_UNORDERED_ACCESS,
-                                   D3D11_USAGE_DEFAULT, 0, 0, 4);
-    int initial_values[4] = {0, 0, 0, 0};
-    D3D11_SUBRESOURCE_DATA data;
-    data.pSysMem = initial_values;
-    data.SysMemPitch = 4 * sizeof(s32);
-    data.SysMemSlicePitch = 0;
-    HRESULT hr;
-    hr = D3D::device->CreateBuffer(&desc, &data, &s_bbox_buffer);
-    CHECK(SUCCEEDED(hr), "Create BoundingBox Buffer.");
-    D3DCommon::SetDebugObjectName(s_bbox_buffer.Get(), "BoundingBox Buffer");
+  if (!g_ActiveConfig.backend_info.bSupportsBBox)
+    return;
 
-    // Second to use as a staging buffer.
-    desc.Usage = D3D11_USAGE_STAGING;
-    desc.CPUAccessFlags = D3D11_CPU_ACCESS_READ;
-    desc.BindFlags = 0;
-    hr = D3D::device->CreateBuffer(&desc, nullptr, &s_bbox_staging_buffer);
-    CHECK(SUCCEEDED(hr), "Create BoundingBox Staging Buffer.");
-    D3DCommon::SetDebugObjectName(s_bbox_staging_buffer.Get(), "BoundingBox Staging Buffer");
+  // Create 2 buffers here.
+  // First for unordered access on default pool.
+  auto desc = CD3D11_BUFFER_DESC(NUM_BBOX_VALUES * sizeof(s32), D3D11_BIND_UNORDERED_ACCESS,
+                                 D3D11_USAGE_DEFAULT, 0, 0, sizeof(s32));
+  const s32 initial_values[NUM_BBOX_VALUES] = {0, 0, 0, 0};
+  D3D11_SUBRESOURCE_DATA data;
+  data.pSysMem = initial_values;
+  data.SysMemPitch = NUM_BBOX_VALUES * sizeof(s32);
+  data.SysMemSlicePitch = 0;
+  HRESULT hr;
+  hr = D3D::device->CreateBuffer(&desc, &data, &s_bbox_buffer);
+  CHECK(SUCCEEDED(hr), "Create BoundingBox Buffer.");
+  D3DCommon::SetDebugObjectName(s_bbox_buffer.Get(), "BoundingBox Buffer");
 
-    // UAV is required to allow concurrent access.
-    D3D11_UNORDERED_ACCESS_VIEW_DESC UAVdesc = {};
-    UAVdesc.Format = DXGI_FORMAT_R32_SINT;
-    UAVdesc.ViewDimension = D3D11_UAV_DIMENSION_BUFFER;
-    UAVdesc.Buffer.FirstElement = 0;
-    UAVdesc.Buffer.Flags = 0;
-    UAVdesc.Buffer.NumElements = 4;
-    hr = D3D::device->CreateUnorderedAccessView(s_bbox_buffer.Get(), &UAVdesc, &s_bbox_uav);
-    CHECK(SUCCEEDED(hr), "Create BoundingBox UAV.");
-    D3DCommon::SetDebugObjectName(s_bbox_uav.Get(), "BoundingBox UAV");
-    D3D::stateman->SetOMUAV(s_bbox_uav.Get());
-  }
+  // Second to use as a staging buffer.
+  desc.Usage = D3D11_USAGE_STAGING;
+  desc.CPUAccessFlags = D3D11_CPU_ACCESS_READ;
+  desc.BindFlags = 0;
+  hr = D3D::device->CreateBuffer(&desc, nullptr, &s_bbox_staging_buffer);
+  CHECK(SUCCEEDED(hr), "Create BoundingBox Staging Buffer.");
+  D3DCommon::SetDebugObjectName(s_bbox_staging_buffer.Get(), "BoundingBox Staging Buffer");
+
+  // UAV is required to allow concurrent access.
+  D3D11_UNORDERED_ACCESS_VIEW_DESC UAVdesc = {};
+  UAVdesc.Format = DXGI_FORMAT_R32_SINT;
+  UAVdesc.ViewDimension = D3D11_UAV_DIMENSION_BUFFER;
+  UAVdesc.Buffer.FirstElement = 0;
+  UAVdesc.Buffer.Flags = 0;
+  UAVdesc.Buffer.NumElements = NUM_BBOX_VALUES;
+  hr = D3D::device->CreateUnorderedAccessView(s_bbox_buffer.Get(), &UAVdesc, &s_bbox_uav);
+  CHECK(SUCCEEDED(hr), "Create BoundingBox UAV.");
+  D3DCommon::SetDebugObjectName(s_bbox_uav.Get(), "BoundingBox UAV");
+  D3D::stateman->SetOMUAV(s_bbox_uav.Get());
+
+  s_bbox_dirty = {};
+  s_bbox_valid = true;
 }
 
 void BBox::Shutdown()
@@ -67,23 +77,73 @@ void BBox::Shutdown()
   s_bbox_buffer.Reset();
 }
 
-void BBox::Set(int index, int value)
+void BBox::Flush()
 {
-  D3D11_BOX box{index * sizeof(s32), 0, 0, (index + 1) * sizeof(s32), 1, 1};
-  D3D::context->UpdateSubresource(s_bbox_buffer.Get(), 0, &box, &value, 0, 0);
+  s_bbox_valid = false;
+
+  if (std::none_of(s_bbox_dirty.begin(), s_bbox_dirty.end(), [](bool dirty) { return dirty; }))
+    return;
+
+  for (u32 start = 0; start < NUM_BBOX_VALUES;)
+  {
+    if (!s_bbox_dirty[start])
+    {
+      start++;
+      continue;
+    }
+
+    u32 end = start + 1;
+    s_bbox_dirty[start] = false;
+    for (; end < NUM_BBOX_VALUES; end++)
+    {
+      if (!s_bbox_dirty[end])
+        break;
+
+      s_bbox_dirty[end] = false;
+    }
+
+    D3D11_BOX box{start * sizeof(s32), 0, 0, end * sizeof(s32), 1, 1};
+    D3D::context->UpdateSubresource(s_bbox_buffer.Get(), 0, &box, &s_bbox_values[start], 0, 0);
+  }
 }
 
-int BBox::Get(int index)
+void BBox::Readback()
 {
-  int data = 0;
   D3D::context->CopyResource(s_bbox_staging_buffer.Get(), s_bbox_buffer.Get());
+
   D3D11_MAPPED_SUBRESOURCE map;
   HRESULT hr = D3D::context->Map(s_bbox_staging_buffer.Get(), 0, D3D11_MAP_READ, 0, &map);
   if (SUCCEEDED(hr))
   {
-    data = ((s32*)map.pData)[index];
+    for (u32 i = 0; i < NUM_BBOX_VALUES; i++)
+    {
+      if (!s_bbox_dirty[i])
+      {
+        std::memcpy(&s_bbox_values[i], reinterpret_cast<const u8*>(map.pData) + sizeof(s32) * i,
+                    sizeof(s32));
+      }
+    }
+
+    D3D::context->Unmap(s_bbox_staging_buffer.Get(), 0);
   }
-  D3D::context->Unmap(s_bbox_staging_buffer.Get(), 0);
-  return data;
+
+  s_bbox_valid = true;
+}
+
+void BBox::Set(int index, int value)
+{
+  if (s_bbox_valid && s_bbox_values[index] == value)
+    return;
+
+  s_bbox_values[index] = value;
+  s_bbox_dirty[index] = true;
+}
+
+int BBox::Get(int index)
+{
+  if (!s_bbox_valid)
+    Readback();
+
+  return s_bbox_values[index];
 }
 };  // namespace DX11

Source/Core/VideoBackends/D3D/D3DBoundingBox.h

@@ -14,6 +14,9 @@ public:
   static void Init();
   static void Shutdown();
 
+  static void Flush();
+  static void Readback();
+
   static void Set(int index, int value);
   static int Get(int index);
 };

Source/Core/VideoBackends/D3D/D3DRender.cpp

@@ -274,6 +274,11 @@ void Renderer::BBoxWriteImpl(int index, u16 value)
   BBox::Set(index, value);
 }
 
+void Renderer::BBoxFlushImpl()
+{
+  BBox::Flush();
+}
+
 void Renderer::Flush()
 {
   D3D::context->Flush();

Source/Core/VideoBackends/D3D/D3DRender.h

@@ -63,6 +63,7 @@ public:
 
   u16 BBoxReadImpl(int index) override;
   void BBoxWriteImpl(int index, u16 value) override;
+  void BBoxFlushImpl() override;
 
   void Flush() override;
   void WaitForGPUIdle() override;