1 files changed, 121 insertions, 13 deletions

diff --git a/Source/Core/VideoBackends/D3D12/BoundingBox.cpp b/Source/Core/VideoBackends/D3D12/BoundingBox.cpp
index d847924cf2..b9ee9b4929 100644
--- a/Source/Core/VideoBackends/D3D12/BoundingBox.cpp
+++ b/Source/Core/VideoBackends/D3D12/BoundingBox.cpp
@@ -2,43 +2,151 @@
 // Licensed under GPLv2+
 // Refer to the license.txt file included.
 
+#include <memory>
+
 #include "Common/CommonTypes.h"
 #include "Common/MsgHandler.h"
 #include "VideoBackends/D3D12/BoundingBox.h"
+#include "VideoBackends/D3D12/D3DBase.h"
+#include "VideoBackends/D3D12/D3DCommandListManager.h"
+#include "VideoBackends/D3D12/D3DDescriptorHeapManager.h"
+#include "VideoBackends/D3D12/D3DStreamBuffer.h"
+#include "VideoBackends/D3D12/D3DUtil.h"
+#include "VideoBackends/D3D12/FramebufferManager.h"
+#include "VideoBackends/D3D12/Render.h"
 #include "VideoCommon/VideoConfig.h"
 
-// D3D12TODO: Support bounding box behavior.
 namespace DX12
 {
 
-ID3D11UnorderedAccessView* BBox::GetUAV()
+constexpr size_t BBOX_BUFFER_SIZE = sizeof(int) * 4;
+constexpr size_t BBOX_STREAM_BUFFER_SIZE = BBOX_BUFFER_SIZE * 128;
+
+static ID3D12Resource* s_bbox_buffer;
+static ID3D12Resource* s_bbox_staging_buffer;
+static void* s_bbox_staging_buffer_map;
+static std::unique_ptr<D3DStreamBuffer> s_bbox_stream_buffer;
+static D3D12_GPU_DESCRIPTOR_HANDLE s_bbox_descriptor_handle;
+
+void BBox::Init()
+{
+	CD3DX12_RESOURCE_DESC buffer_desc(CD3DX12_RESOURCE_DESC::Buffer(BBOX_BUFFER_SIZE, D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS, 0));
+	CD3DX12_RESOURCE_DESC staging_buffer_desc(CD3DX12_RESOURCE_DESC::Buffer(BBOX_BUFFER_SIZE, D3D12_RESOURCE_FLAG_NONE, 0));
+
+	CheckHR(D3D::device12->CreateCommittedResource(
+		&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT),
+		D3D12_HEAP_FLAG_NONE,
+		&buffer_desc,
+		D3D12_RESOURCE_STATE_UNORDERED_ACCESS,
+		nullptr,
+		IID_PPV_ARGS(&s_bbox_buffer)));
+
+	CheckHR(D3D::device12->CreateCommittedResource(
+		&CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_READBACK),
+		D3D12_HEAP_FLAG_NONE,
+		&staging_buffer_desc,
+		D3D12_RESOURCE_STATE_COPY_DEST,
+		nullptr,
+		IID_PPV_ARGS(&s_bbox_staging_buffer)));
+
+	s_bbox_stream_buffer = std::make_unique<D3DStreamBuffer>(BBOX_STREAM_BUFFER_SIZE, BBOX_STREAM_BUFFER_SIZE, nullptr);
+
+	// D3D12 root signature UAV must be raw or structured buffers, not typed. Since we used a typed buffer,
+	// we have to use a descriptor table. Luckily, we only have to allocate this once, and it never changes.
+	D3D12_CPU_DESCRIPTOR_HANDLE cpu_descriptor_handle;
+	if (!D3D::gpu_descriptor_heap_mgr->Allocate(&cpu_descriptor_handle, &s_bbox_descriptor_handle, nullptr, false))
+		PanicAlert("Failed to create bounding box UAV descriptor");
+
+	D3D12_UNORDERED_ACCESS_VIEW_DESC view_desc = { DXGI_FORMAT_R32_SINT, D3D12_UAV_DIMENSION_BUFFER };
+	view_desc.Buffer.FirstElement = 0;
+	view_desc.Buffer.NumElements = 4;
+	view_desc.Buffer.StructureByteStride = 0;
+	view_desc.Buffer.CounterOffsetInBytes = 0;
+	view_desc.Buffer.Flags = D3D12_BUFFER_UAV_FLAG_NONE;
+	D3D::device12->CreateUnorderedAccessView(s_bbox_buffer, nullptr, &view_desc, cpu_descriptor_handle);
+
+	Bind();
+}
+
+void BBox::Bind()
 {
-	// D3D12TODO: Implement this;
-	return nullptr;
+	D3D::current_command_list->SetGraphicsRootDescriptorTable(DESCRIPTOR_TABLE_PS_UAV, s_bbox_descriptor_handle);
 }
 
-void BBox::Init()
+void BBox::Invalidate()
 {
-	if (g_ActiveConfig.backend_info.bSupportsBBox)
-	{
-		// D3D12TODO: Implement this;
-	}
+	if (!s_bbox_staging_buffer_map)
+		return;
+
+	D3D12_RANGE write_range = {};
+	s_bbox_staging_buffer->Unmap(0, &write_range);
+	s_bbox_staging_buffer_map = nullptr;
 }
 
 void BBox::Shutdown()
 {
-	// D3D12TODO: Implement this;
+	Invalidate();
+
+	if (s_bbox_buffer)
+	{
+		D3D::command_list_mgr->DestroyResourceAfterCurrentCommandListExecuted(s_bbox_buffer);
+		s_bbox_buffer = nullptr;
+	}
+
+	if (s_bbox_staging_buffer)
+	{
+		D3D::command_list_mgr->DestroyResourceAfterCurrentCommandListExecuted(s_bbox_staging_buffer);
+		s_bbox_staging_buffer = nullptr;
+	}
+
+	s_bbox_stream_buffer.reset();
 }
 
 void BBox::Set(int index, int value)
 {
-	// D3D12TODO: Implement this;
+	// If the buffer is currently mapped, compare the value, and update the staging buffer.
+	if (s_bbox_staging_buffer_map)
+	{
+		int current_value;
+		memcpy(&current_value, reinterpret_cast<u8*>(s_bbox_staging_buffer_map) + (index * sizeof(int)), sizeof(int));
+		if (current_value == value)
+		{
+			// Value hasn't changed. So skip updating completely.
+			return;
+		}
+
+		memcpy(reinterpret_cast<u8*>(s_bbox_staging_buffer_map) + (index * sizeof(int)), &value, sizeof(int));
+	}
+
+	s_bbox_stream_buffer->AllocateSpaceInBuffer(sizeof(int), sizeof(int));
+
+	// Allocate temporary bytes in upload buffer, then copy to real buffer.
+	memcpy(s_bbox_stream_buffer->GetCPUAddressOfCurrentAllocation(), &value, sizeof(int));
+	D3D::ResourceBarrier(D3D::current_command_list, s_bbox_buffer, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, D3D12_RESOURCE_STATE_COPY_DEST, 0);
+	D3D::current_command_list->CopyBufferRegion(s_bbox_buffer, index * sizeof(int), s_bbox_stream_buffer->GetBuffer(), s_bbox_stream_buffer->GetOffsetOfCurrentAllocation(), sizeof(int));
+	D3D::ResourceBarrier(D3D::current_command_list, s_bbox_buffer, D3D12_RESOURCE_STATE_COPY_DEST, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, 0);
 }
 
 int BBox::Get(int index)
 {
-	// D3D12TODO: Implement this;
-	return 0;
+	if (!s_bbox_staging_buffer_map)
+	{
+		D3D::command_list_mgr->CPUAccessNotify();
+
+		// Copy from real buffer to staging buffer, then block until we have the results.
+		D3D::ResourceBarrier(D3D::current_command_list, s_bbox_buffer, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, D3D12_RESOURCE_STATE_COPY_SOURCE, 0);
+		D3D::current_command_list->CopyBufferRegion(s_bbox_staging_buffer, 0, s_bbox_buffer, 0, BBOX_BUFFER_SIZE);
+		D3D::ResourceBarrier(D3D::current_command_list, s_bbox_buffer, D3D12_RESOURCE_STATE_COPY_SOURCE, D3D12_RESOURCE_STATE_UNORDERED_ACCESS, 0);
+
+		D3D::command_list_mgr->ExecuteQueuedWork(true);
+
+		D3D12_RANGE read_range = { 0, BBOX_BUFFER_SIZE };
+		CheckHR(s_bbox_staging_buffer->Map(0, &read_range, &s_bbox_staging_buffer_map));
+	}
+
+	int value;
+	memcpy(&value, &reinterpret_cast<int*>(s_bbox_staging_buffer_map)[index], sizeof(int));
+	return value;
 }
 
 };