让我们在场景中添加一些颜色。 在本教程中，我们将为顶点添加颜色以为三角形着色。 这涉及更新顶点着色器以将颜色传递给像素着色器，像素着色器以输出传递给它的颜色，顶点结构添加颜色属性，输入布局包含颜色输入元素。
介绍在本教程中，我们将为三角形添加颜色。 这涉及向顶点结构添加属性，更改顶点着色器以接受颜色并将其传递，更新像素着色器以返回从光栅化器传递给它的插值像素颜色，并将输入元素添加到 输入布局
新的顶点结构
这是一个很短的教程，所以我们现在就可以开始。我们可以定义一个具有4个浮点变量的结构，一个用于红色通道，一个用于绿色通道，一个用于蓝色通道，一个用于alpha通道。 我们可以使用DirectX数学XMFLOAT4类型来做到这一点。
除了在顶点结构中添加XMFLOAT4之外，我们还将在顶点结构中添加一个构造函数，以使创建顶点更加容易。更新了输入布局struct Vertex { Vertex(float x, float y, float z, float r, float g, float b, float a) : pos(x, y, z), color(r, g, b, z) {} XMFLOAT3 pos; XMFLOAT4 color; };我们将在输入布局中添加一个颜色元素。 我们的颜色是4个浮点值，因此我们将DXGI_FORMAT_R32G32B32A32_FLOAT用作元素格式。 它是在position属性之后定义的，它是12个字节，因此我们需要说color元素从顶点结构开始的12个字节，这就是第五个参数为12的原因。
新顶点数组D3D12_INPUT_ELEMENT_DESC inputLayout[] = { { "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 }, { "COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 12, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 } };我们将为三角形创建的每个顶点添加一个颜色值。 第一个顶点将为红色，第二个顶点将为绿色，第三个顶点将为蓝色。 我们可以这样定义顶点，因为我们添加了自定义顶点结构构造函数。
顶点着色器Vertex vList[] = { { 0.0f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f }, { 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f }, { -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f }, };我们向顶点着色器文件添加了两个结构。 输入有一个结构，输出有一个结构。 顶点着色器中的输出结构需要匹配像素着色器作为输入的结构。 我们使用相同的结构代码。
请注意，SV_POSITION语义已从主要参数列表的右侧移至VS_OUTPUT结构中的pos变量的右侧。 SV_POSITION语义是系统语义。 顶点着色器必须返回顶点的位置（与SV_POSITION语义相关联），以便下一个流水线阶段（例如，光栅化器）可以读取该顶点。 然后，光栅化阶段将在多边形表面（或线）上插入顶点属性。
我们的顶点着色器仍然非常非常简单。 我们要做的就是创建一个VS_OUTPUT对象，用传递到顶点着色器中的位置和颜色填充它。像素着色器struct VS_INPUT { float3 pos : POSITION; float4 color: COLOR; }; struct VS_OUTPUT { float4 pos: SV_POSITION; float4 color: COLOR; }; VS_OUTPUT main(VS_INPUT input) { VS_OUTPUT output; output.pos = float4(input.pos, 1.0f); output.color = input.color; return output; }像素着色器必须返回与SV_TARGET语义相关联的float4。 SV_语义是系统值语义，并且由管道使用。
顶点属性（本教程中的颜色）在三角形表面上插值。 内插的值将传递给该三角形中每个像素的像素着色器。 在本教程中，我们要做的就是从像素着色器返回插值的颜色。struct VS_OUTPUT { float4 pos: SV_POSITION; float4 color: COLOR; }; float4 main(VS_OUTPUT input) : SV_TARGET { // return interpolated color return input.color; }这就是添加颜色的全部，希望您能学到一些知识〜
源代码
VertexShader.hlslstruct VS_INPUT { float3 pos : POSITION; float4 color: COLOR; }; struct VS_OUTPUT { float4 pos: SV_POSITION; float4 color: COLOR; }; VS_OUTPUT main(VS_INPUT input) { VS_OUTPUT output; output.pos = float4(input.pos, 1.0f); output.color = input.color; return output; }PixelShader.hlsl
struct VS_OUTPUT { float4 pos: SV_POSITION; float4 color: COLOR; }; float4 main(VS_OUTPUT input) : SV_TARGET { // return interpolated color return input.color; }stdafx.h
#pragma once #ifndef WIN32_LEAN_AND_MEAN #define WIN32_LEAN_AND_MEAN // Exclude rarely-used stuff from Windows headers. #endif #include <windows.h> #include <d3d12.h> #include <dxgi1_4.h> #include <D3Dcompiler.h> #include <DirectXMath.h> #include "d3dx12.h" #include <string> // this will only call release if an object exists (prevents exceptions calling release on non existant objects) #define SAFE_RELEASE(p) { if ( (p) ) { (p)->Release(); (p) = 0; } } // Handle to the window HWND hwnd = NULL; // name of the window (not the title) LPCTSTR WindowName = L"BzTutsApp"; // title of the window LPCTSTR WindowTitle = L"Bz Window"; // width and height of the window int Width = 800; int Height = 600; // is window full screen? bool FullScreen = false; // we will exit the program when this becomes false bool Running = true; // create a window bool InitializeWindow(HINSTANCE hInstance, int ShowWnd, bool fullscreen); // main application loop void mainloop(); // callback function for windows messages LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam); // direct3d stuff const int frameBufferCount = 3; // number of buffers we want, 2 for double buffering, 3 for tripple buffering ID3D12Device* device; // direct3d device IDXGISwapChain3* swapChain; // swapchain used to switch between render targets ID3D12CommandQueue* commandQueue; // container for command lists ID3D12DescriptorHeap* rtvDescriptorHeap; // a descriptor heap to hold resources like the render targets ID3D12Resource* renderTargets[frameBufferCount]; // number of render targets equal to buffer count ID3D12CommandAllocator* commandAllocator[frameBufferCount]; // we want enough allocators for each buffer * number of threads (we only have one thread) ID3D12GraphicsCommandList* commandList; // a command list we can record commands into, then execute them to render the frame ID3D12Fence* fence[frameBufferCount]; // an object that is locked while our command list is being executed by the gpu. We need as many //as we have allocators (more if we want to know when the gpu is finished with an asset) HANDLE fenceEvent; // a handle to an event when our fence is unlocked by the gpu UINT64 fenceValue[frameBufferCount]; // this value is incremented each frame. each fence will have its own value int frameIndex; // current rtv we are on int rtvDescriptorSize; // size of the rtv descriptor on the device (all front and back buffers will be the same size) // function declarations bool InitD3D(); // initializes direct3d 12 void Update(); // update the game logic void UpdatePipeline(); // update the direct3d pipeline (update command lists) void Render(); // execute the command list void Cleanup(); // release com ojects and clean up memory void WaitForPreviousFrame(); // wait until gpu is finished with command list ID3D12PipelineState* pipelineStateObject; // pso containing a pipeline state ID3D12RootSignature* rootSignature; // root signature defines data shaders will access D3D12_VIEWPORT viewport; // area that output from rasterizer will be stretched to. D3D12_RECT scissorRect; // the area to draw in. pixels outside that area will not be drawn onto ID3D12Resource* vertexBuffer; // a default buffer in GPU memory that we will load vertex data for our triangle into D3D12_VERTEX_BUFFER_VIEW vertexBufferView; // a structure containing a pointer to the vertex data in gpu memory // the total size of the buffer, and the size of each element (vertex)main.cpp
#include "stdafx.h" using namespace DirectX; // we will be using the directxmath library struct Vertex { Vertex(float x, float y, float z, float r, float g, float b, float a) : pos(x, y, z), color(r, g, b, z) {} XMFLOAT3 pos; XMFLOAT4 color; }; int WINAPI WinMain(HINSTANCE hInstance, //Main windows function HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd) { // create the window if (!InitializeWindow(hInstance, nShowCmd, FullScreen)) { MessageBox(0, L"Window Initialization - Failed", L"Error", MB_OK); return 1; } // initialize direct3d if (!InitD3D()) { MessageBox(0, L"Failed to initialize direct3d 12", L"Error", MB_OK); Cleanup(); return 1; } // start the main loop mainloop(); // we want to wait for the gpu to finish executing the command list before we start releasing everything WaitForPreviousFrame(); // close the fence event CloseHandle(fenceEvent); // clean up everything Cleanup(); return 0; } // create and show the window bool InitializeWindow(HINSTANCE hInstance, int ShowWnd, bool fullscreen) { if (fullscreen) { HMONITOR hmon = MonitorFromWindow(hwnd, MONITOR_DEFAULTTONEAREST); MONITORINFO mi = { sizeof(mi) }; GetMonitorInfo(hmon, &mi); Width = mi.rcMonitor.right - mi.rcMonitor.left; Height = mi.rcMonitor.bottom - mi.rcMonitor.top; } WNDCLASSEX wc; wc.cbSize = sizeof(WNDCLASSEX); wc.style = CS_HREDRAW | CS_VREDRAW; wc.lpfnWndProc = WndProc; wc.cbClsExtra = NULL; wc.cbWndExtra = NULL; wc.hInstance = hInstance; wc.hIcon = LoadIcon(NULL, IDI_APPLICATION); wc.hCursor = LoadCursor(NULL, IDC_ARROW); wc.hbrBackground = (HBRUSH)(COLOR_WINDOW + 2); wc.lpszMenuName = NULL; wc.lpszClassName = WindowName; wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION); if (!RegisterClassEx(&wc)) { MessageBox(NULL, L"Error registering class", L"Error", MB_OK | MB_ICONERROR); return false; } hwnd = CreateWindowEx(NULL, WindowName, WindowTitle, WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, Width, Height, NULL, NULL, hInstance, NULL); if (!hwnd) { MessageBox(NULL, L"Error creating window", L"Error", MB_OK | MB_ICONERROR); return false; } if (fullscreen) { SetWindowLong(hwnd, GWL_STYLE, 0); } ShowWindow(hwnd, ShowWnd); UpdateWindow(hwnd); return true; } void mainloop() { MSG msg; ZeroMemory(&msg, sizeof(MSG)); while (Running) { if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) { if (msg.message == WM_QUIT) break; TranslateMessage(&msg); DispatchMessage(&msg); } else { // run game code Update(); // update the game logic Render(); // execute the command queue (rendering the scene is the result of the gpu executing the command lists) } } } LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) { switch (msg) { case WM_KEYDOWN: if (wParam == VK_ESCAPE) { if (MessageBox(0, L"Are you sure you want to exit?", L"Really?", MB_YESNO | MB_ICONQUESTION) == IDYES) { Running = false; DestroyWindow(hwnd); } } return 0; case WM_DESTROY: // x button on top right corner of window was pressed Running = false; PostQuitMessage(0); return 0; } return DefWindowProc(hwnd, msg, wParam, lParam); } bool InitD3D() { HRESULT hr; // -- Create the Device -- // IDXGIFactory4* dxgiFactory; hr = CreateDXGIFactory1(IID_PPV_ARGS(&dxgiFactory)); if (FAILED(hr)) { return false; } IDXGIAdapter1* adapter; // adapters are the graphics card (this includes the embedded graphics on the motherboard) int adapterIndex = 0; // we'll start looking for directx 12 compatible graphics devices starting at index 0 bool adapterFound = false; // set this to true when a good one was found // find first hardware gpu that supports d3d 12 while (dxgiFactory->EnumAdapters1(adapterIndex, &adapter) != DXGI_ERROR_NOT_FOUND) { DXGI_ADAPTER_DESC1 desc; adapter->GetDesc1(&desc); if (desc.Flags & DXGI_ADAPTER_FLAG_SOFTWARE) { // we dont want a software device continue; } // we want a device that is compatible with direct3d 12 (feature level 11 or higher) hr = D3D12CreateDevice(adapter, D3D_FEATURE_LEVEL_11_0, _uuidof(ID3D12Device), nullptr); if (SUCCEEDED(hr)) { adapterFound = true; break; } adapterIndex++; } if (!adapterFound) { return false; } // Create the device hr = D3D12CreateDevice( adapter, D3D_FEATURE_LEVEL_11_0, IID_PPV_ARGS(&device) ); if (FAILED(hr)) { return false; } // -- Create a direct command queue -- // D3D12_COMMAND_QUEUE_DESC cqDesc = {}; cqDesc.Flags = D3D12_COMMAND_QUEUE_FLAG_NONE; cqDesc.Type = D3D12_COMMAND_LIST_TYPE_DIRECT; // direct means the gpu can directly execute this command queue hr = device->CreateCommandQueue(&cqDesc, IID_PPV_ARGS(&commandQueue)); // create the command queue if (FAILED(hr)) { return false; } // -- Create the Swap Chain (double/tripple buffering) -- // DXGI_MODE_DESC backBufferDesc = {}; // this is to describe our display mode backBufferDesc.Width = Width; // buffer width backBufferDesc.Height = Height; // buffer height backBufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM; // format of the buffer (rgba 32 bits, 8 bits for each chanel) // describe our multi-sampling. We are not multi-sampling, so we set the count to 1 (we need at least one sample of course) DXGI_SAMPLE_DESC sampleDesc = {}; sampleDesc.Count = 1; // multisample count (no multisampling, so we just put 1, since we still need 1 sample) // Describe and create the swap chain. DXGI_SWAP_CHAIN_DESC swapChainDesc = {}; swapChainDesc.BufferCount = frameBufferCount; // number of buffers we have swapChainDesc.BufferDesc = backBufferDesc; // our back buffer description swapChainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT; // this says the pipeline will render to this swap chain swapChainDesc.SwapEffect = DXGI_SWAP_EFFECT_FLIP_DISCARD; // dxgi will discard the buffer (data) after we call present swapChainDesc.OutputWindow = hwnd; // handle to our window swapChainDesc.SampleDesc = sampleDesc; // our multi-sampling description swapChainDesc.Windowed = !FullScreen; // set to true, then if in fullscreen must call SetFullScreenState with true for full screen to get uncapped fps IDXGISwapChain* tempSwapChain; dxgiFactory->CreateSwapChain( commandQueue, // the queue will be flushed once the swap chain is created &swapChainDesc, // give it the swap chain description we created above &tempSwapChain // store the created swap chain in a temp IDXGISwapChain interface ); swapChain = static_cast<IDXGISwapChain3*>(tempSwapChain); frameIndex = swapChain->GetCurrentBackBufferIndex(); // -- Create the Back Buffers (render target views) Descriptor Heap -- // // describe an rtv descriptor heap and create D3D12_DESCRIPTOR_HEAP_DESC rtvHeapDesc = {}; rtvHeapDesc.NumDescriptors = frameBufferCount; // number of descriptors for this heap. rtvHeapDesc.Type = D3D12_DESCRIPTOR_HEAP_TYPE_RTV; // this heap is a render target view heap // This heap will not be directly referenced by the shaders (not shader visible), as this will store the output from the pipeline // otherwise we would set the heap's flag to D3D12_DESCRIPTOR_HEAP_FLAG_SHADER_VISIBLE rtvHeapDesc.Flags = D3D12_DESCRIPTOR_HEAP_FLAG_NONE; hr = device->CreateDescriptorHeap(&rtvHeapDesc, IID_PPV_ARGS(&rtvDescriptorHeap)); if (FAILED(hr)) { return false; } // get the size of a descriptor in this heap (this is a rtv heap, so only rtv descriptors should be stored in it. // descriptor sizes may vary from device to device, which is why there is no set size and we must ask the // device to give us the size. we will use this size to increment a descriptor handle offset rtvDescriptorSize = device->GetDescriptorHandleIncrementSize(D3D12_DESCRIPTOR_HEAP_TYPE_RTV); // get a handle to the first descriptor in the descriptor heap. a handle is basically a pointer, // but we cannot literally use it like a c++ pointer. CD3DX12_CPU_DESCRIPTOR_HANDLE rtvHandle(rtvDescriptorHeap->GetCPUDescriptorHandleForHeapStart()); // Create a RTV for each buffer (double buffering is two buffers, tripple buffering is 3). for (int i = 0; i < frameBufferCount; i++) { // first we get the n'th buffer in the swap chain and store it in the n'th // position of our ID3D12Resource array hr = swapChain->GetBuffer(i, IID_PPV_ARGS(&renderTargets[i])); if (FAILED(hr)) { return false; } // the we "create" a render target view which binds the swap chain buffer (ID3D12Resource[n]) to the rtv handle device->CreateRenderTargetView(renderTargets[i], nullptr, rtvHandle); // we increment the rtv handle by the rtv descriptor size we got above rtvHandle.Offset(1, rtvDescriptorSize); } // -- Create the Command Allocators -- // for (int i = 0; i < frameBufferCount; i++) { hr = device->CreateCommandAllocator(D3D12_COMMAND_LIST_TYPE_DIRECT, IID_PPV_ARGS(&commandAllocator[i])); if (FAILED(hr)) { return false; } } // -- Create a Command List -- // // create the command list with the first allocator hr = device->CreateCommandList(0, D3D12_COMMAND_LIST_TYPE_DIRECT, commandAllocator[frameIndex], NULL, IID_PPV_ARGS(&commandList)); if (FAILED(hr)) { return false; } // -- Create a Fence & Fence Event -- // // create the fences for (int i = 0; i < frameBufferCount; i++) { hr = device->CreateFence(0, D3D12_FENCE_FLAG_NONE, IID_PPV_ARGS(&fence[i])); if (FAILED(hr)) { return false; } fenceValue[i] = 0; // set the initial fence value to 0 } // create a handle to a fence event fenceEvent = CreateEvent(nullptr, FALSE, FALSE, nullptr); if (fenceEvent == nullptr) { return false; } // create root signature CD3DX12_ROOT_SIGNATURE_DESC rootSignatureDesc; rootSignatureDesc.Init(0, nullptr, 0, nullptr, D3D12_ROOT_SIGNATURE_FLAG_ALLOW_INPUT_ASSEMBLER_INPUT_LAYOUT); ID3DBlob* signature; hr = D3D12SerializeRootSignature(&rootSignatureDesc, D3D_ROOT_SIGNATURE_VERSION_1, &signature, nullptr); if (FAILED(hr)) { return false; } hr = device->CreateRootSignature(0, signature->GetBufferPointer(), signature->GetBufferSize(), IID_PPV_ARGS(&rootSignature)); if (FAILED(hr)) { return false; } // create vertex and pixel shaders // when debugging, we can compile the shader files at runtime. // but for release versions, we can compile the hlsl shaders // with fxc.exe to create .cso files, which contain the shader // bytecode. We can load the .cso files at runtime to get the // shader bytecode, which of course is faster than compiling // them at runtime // compile vertex shader ID3DBlob* vertexShader; // d3d blob for holding vertex shader bytecode ID3DBlob* errorBuff; // a buffer holding the error data if any hr = D3DCompileFromFile(L"VertexShader.hlsl", nullptr, nullptr, "main", "vs_5_0", D3DCOMPILE_DEBUG | D3DCOMPILE_SKIP_OPTIMIZATION, 0, &vertexShader, &errorBuff); if (FAILED(hr)) { OutputDebugStringA((char*)errorBuff->GetBufferPointer()); return false; } // fill out a shader bytecode structure, which is basically just a pointer // to the shader bytecode and the size of the shader bytecode D3D12_SHADER_BYTECODE vertexShaderBytecode = {}; vertexShaderBytecode.BytecodeLength = vertexShader->GetBufferSize(); vertexShaderBytecode.pShaderBytecode = vertexShader->GetBufferPointer(); // compile pixel shader ID3DBlob* pixelShader; hr = D3DCompileFromFile(L"PixelShader.hlsl", nullptr, nullptr, "main", "ps_5_0", D3DCOMPILE_DEBUG | D3DCOMPILE_SKIP_OPTIMIZATION, 0, &pixelShader, &errorBuff); if (FAILED(hr)) { OutputDebugStringA((char*)errorBuff->GetBufferPointer()); return false; } // fill out shader bytecode structure for pixel shader D3D12_SHADER_BYTECODE pixelShaderBytecode = {}; pixelShaderBytecode.BytecodeLength = pixelShader->GetBufferSize(); pixelShaderBytecode.pShaderBytecode = pixelShader->GetBufferPointer(); // create input layout // The input layout is used by the Input Assembler so that it knows // how to read the vertex data bound to it. D3D12_INPUT_ELEMENT_DESC inputLayout[] = { { "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 }, { "COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 12, D3D12_INPUT_CLASSIFICATION_PER_VERTEX_DATA, 0 } }; // fill out an input layout description structure D3D12_INPUT_LAYOUT_DESC inputLayoutDesc = {}; // we can get the number of elements in an array by "sizeof(array) / sizeof(arrayElementType)" inputLayoutDesc.NumElements = sizeof(inputLayout) / sizeof(D3D12_INPUT_ELEMENT_DESC); inputLayoutDesc.pInputElementDescs = inputLayout; // create a pipeline state object (PSO) // In a real application, you will have many pso's. for each different shader // or different combinations of shaders, different blend states or different rasterizer states, // different topology types (point, line, triangle, patch), or a different number // of render targets you will need a pso // VS is the only required shader for a pso. You might be wondering when a case would be where // you only set the VS. It's possible that you have a pso that only outputs data with the stream // output, and not on a render target, which means you would not need anything after the stream // output. D3D12_GRAPHICS_PIPELINE_STATE_DESC psoDesc = {}; // a structure to define a pso psoDesc.InputLayout = inputLayoutDesc; // the structure describing our input layout psoDesc.pRootSignature = rootSignature; // the root signature that describes the input data this pso needs psoDesc.VS = vertexShaderBytecode; // structure describing where to find the vertex shader bytecode and how large it is psoDesc.PS = pixelShaderBytecode; // same as VS but for pixel shader psoDesc.PrimitiveTopologyType = D3D12_PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE; // type of topology we are drawing psoDesc.RTVFormats[0] = DXGI_FORMAT_R8G8B8A8_UNORM; // format of the render target psoDesc.SampleDesc = sampleDesc; // must be the same sample description as the swapchain and depth/stencil buffer psoDesc.SampleMask = 0xffffffff; // sample mask has to do with multi-sampling. 0xffffffff means point sampling is done psoDesc.RasterizerState = CD3DX12_RASTERIZER_DESC(D3D12_DEFAULT); // a default rasterizer state. psoDesc.BlendState = CD3DX12_BLEND_DESC(D3D12_DEFAULT); // a default blent state. psoDesc.NumRenderTargets = 1; // we are only binding one render target // create the pso hr = device->CreateGraphicsPipelineState(&psoDesc, IID_PPV_ARGS(&pipelineStateObject)); if (FAILED(hr)) { return false; } // Create vertex buffer // a triangle Vertex vList[] = { { 0.0f, 0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f }, { 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f }, { -0.5f, -0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f }, }; int vBufferSize = sizeof(vList); // create default heap // default heap is memory on the GPU. Only the GPU has access to this memory // To get data into this heap, we will have to upload the data using // an upload heap device->CreateCommittedResource( &CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_DEFAULT), // a default heap D3D12_HEAP_FLAG_NONE, // no flags &CD3DX12_RESOURCE_DESC::Buffer(vBufferSize), // resource description for a buffer D3D12_RESOURCE_STATE_COPY_DEST, // we will start this heap in the copy destination state since we will copy data // from the upload heap to this heap nullptr, // optimized clear value must be null for this type of resource. used for render targets and depth/stencil buffers IID_PPV_ARGS(&vertexBuffer)); // we can give resource heaps a name so when we debug with the graphics debugger we know what resource we are looking at vertexBuffer->SetName(L"Vertex Buffer Resource Heap"); // create upload heap // upload heaps are used to upload data to the GPU. CPU can write to it, GPU can read from it // We will upload the vertex buffer using this heap to the default heap ID3D12Resource* vBufferUploadHeap; device->CreateCommittedResource( &CD3DX12_HEAP_PROPERTIES(D3D12_HEAP_TYPE_UPLOAD), // upload heap D3D12_HEAP_FLAG_NONE, // no flags &CD3DX12_RESOURCE_DESC::Buffer(vBufferSize), // resource description for a buffer D3D12_RESOURCE_STATE_GENERIC_READ, // GPU will read from this buffer and copy its contents to the default heap nullptr, IID_PPV_ARGS(&vBufferUploadHeap)); vBufferUploadHeap->SetName(L"Vertex Buffer Upload Resource Heap"); // store vertex buffer in upload heap D3D12_SUBRESOURCE_DATA vertexData = {}; vertexData.pData = reinterpret_cast<BYTE*>(vList); // pointer to our vertex array vertexData.RowPitch = vBufferSize; // size of all our triangle vertex data vertexData.SlicePitch = vBufferSize; // also the size of our triangle vertex data // we are now creating a command with the command list to copy the data from // the upload heap to the default heap UpdateSubresources(commandList, vertexBuffer, vBufferUploadHeap, 0, 0, 1, &vertexData); // transition the vertex buffer data from copy destination state to vertex buffer state commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(vertexBuffer, D3D12_RESOURCE_STATE_COPY_DEST, D3D12_RESOURCE_STATE_VERTEX_AND_CONSTANT_BUFFER)); // Now we execute the command list to upload the initial assets (triangle data) commandList->Close(); ID3D12CommandList* ppCommandLists[] = { commandList }; commandQueue->ExecuteCommandLists(_countof(ppCommandLists), ppCommandLists); // increment the fence value now, otherwise the buffer might not be uploaded by the time we start drawing fenceValue[frameIndex]++; hr = commandQueue->Signal(fence[frameIndex], fenceValue[frameIndex]); if (FAILED(hr)) { Running = false; } // create a vertex buffer view for the triangle. We get the GPU memory address to the vertex pointer using the GetGPUVirtualAddress() method vertexBufferView.BufferLocation = vertexBuffer->GetGPUVirtualAddress(); vertexBufferView.StrideInBytes = sizeof(Vertex); vertexBufferView.SizeInBytes = vBufferSize; // Fill out the Viewport viewport.TopLeftX = 0; viewport.TopLeftY = 0; viewport.Width = Width; viewport.Height = Height; viewport.MinDepth = 0.0f; viewport.MaxDepth = 1.0f; // Fill out a scissor rect scissorRect.left = 0; scissorRect.top = 0; scissorRect.right = Width; scissorRect.bottom = Height; return true; } void Update() { // update app logic, such as moving the camera or figuring out what objects are in view } void UpdatePipeline() { HRESULT hr; // We have to wait for the gpu to finish with the command allocator before we reset it WaitForPreviousFrame(); // we can only reset an allocator once the gpu is done with it // resetting an allocator frees the memory that the command list was stored in hr = commandAllocator[frameIndex]->Reset(); if (FAILED(hr)) { Running = false; } // reset the command list. by resetting the command list we are putting it into // a recording state so we can start recording commands into the command allocator. // the command allocator that we reference here may have multiple command lists // associated with it, but only one can be recording at any time. Make sure // that any other command lists associated to this command allocator are in // the closed state (not recording). // Here you will pass an initial pipeline state object as the second parameter, // but in this tutorial we are only clearing the rtv, and do not actually need // anything but an initial default pipeline, which is what we get by setting // the second parameter to NULL hr = commandList->Reset(commandAllocator[frameIndex], pipelineStateObject); if (FAILED(hr)) { Running = false; } // here we start recording commands into the commandList (which all the commands will be stored in the commandAllocator) // transition the "frameIndex" render target from the present state to the render target state so the command list draws to it starting from here commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(renderTargets[frameIndex], D3D12_RESOURCE_STATE_PRESENT, D3D12_RESOURCE_STATE_RENDER_TARGET)); // here we again get the handle to our current render target view so we can set it as the render target in the output merger stage of the pipeline CD3DX12_CPU_DESCRIPTOR_HANDLE rtvHandle(rtvDescriptorHeap->GetCPUDescriptorHandleForHeapStart(), frameIndex, rtvDescriptorSize); // set the render target for the output merger stage (the output of the pipeline) commandList->OMSetRenderTargets(1, &rtvHandle, FALSE, nullptr); // Clear the render target by using the ClearRenderTargetView command const float clearColor[] = { 0.0f, 0.2f, 0.4f, 1.0f }; commandList->ClearRenderTargetView(rtvHandle, clearColor, 0, nullptr); // draw triangle commandList->SetGraphicsRootSignature(rootSignature); // set the root signature commandList->RSSetViewports(1, &viewport); // set the viewports commandList->RSSetScissorRects(1, &scissorRect); // set the scissor rects commandList->IASetPrimitiveTopology(D3D_PRIMITIVE_TOPOLOGY_TRIANGLELIST); // set the primitive topology commandList->IASetVertexBuffers(0, 1, &vertexBufferView); // set the vertex buffer (using the vertex buffer view) commandList->DrawInstanced(3, 1, 0, 0); // finally draw 3 vertices (draw the triangle) // transition the "frameIndex" render target from the render target state to the present state. If the debug layer is enabled, you will receive a // warning if present is called on the render target when it's not in the present state commandList->ResourceBarrier(1, &CD3DX12_RESOURCE_BARRIER::Transition(renderTargets[frameIndex], D3D12_RESOURCE_STATE_RENDER_TARGET, D3D12_RESOURCE_STATE_PRESENT)); hr = commandList->Close(); if (FAILED(hr)) { Running = false; } } void Render() { HRESULT hr; UpdatePipeline(); // update the pipeline by sending commands to the commandqueue // create an array of command lists (only one command list here) ID3D12CommandList* ppCommandLists[] = { commandList }; // execute the array of command lists commandQueue->ExecuteCommandLists(_countof(ppCommandLists), ppCommandLists); // this command goes in at the end of our command queue. we will know when our command queue // has finished because the fence value will be set to "fenceValue" from the GPU since the command // queue is being executed on the GPU hr = commandQueue->Signal(fence[frameIndex], fenceValue[frameIndex]); if (FAILED(hr)) { Running = false; } // present the current backbuffer hr = swapChain->Present(0, 0); if (FAILED(hr)) { Running = false; } } void Cleanup() { // wait for the gpu to finish all frames for (int i = 0; i < frameBufferCount; ++i) { frameIndex = i; WaitForPreviousFrame(); } // get swapchain out of full screen before exiting BOOL fs = false; if (swapChain->GetFullscreenState(&fs, NULL)) swapChain->SetFullscreenState(false, NULL); SAFE_RELEASE(device); SAFE_RELEASE(swapChain); SAFE_RELEASE(commandQueue); SAFE_RELEASE(rtvDescriptorHeap); SAFE_RELEASE(commandList); for (int i = 0; i < frameBufferCount; ++i) { SAFE_RELEASE(renderTargets[i]); SAFE_RELEASE(commandAllocator[i]); SAFE_RELEASE(fence[i]); }; SAFE_RELEASE(pipelineStateObject); SAFE_RELEASE(rootSignature); SAFE_RELEASE(vertexBuffer); } void WaitForPreviousFrame() { HRESULT hr; // swap the current rtv buffer index so we draw on the correct buffer frameIndex = swapChain->GetCurrentBackBufferIndex(); // if the current fence value is still less than "fenceValue", then we know the GPU has not finished executing // the command queue since it has not reached the "commandQueue->Signal(fence, fenceValue)" command if (fence[frameIndex]->GetCompletedValue() < fenceValue[frameIndex]) { // we have the fence create an event which is signaled once the fence's current value is "fenceValue" hr = fence[frameIndex]->SetEventOnCompletion(fenceValue[frameIndex], fenceEvent); if (FAILED(hr)) { Running = false; } // We will wait until the fence has triggered the event that it's current value has reached "fenceValue". once it's value // has reached "fenceValue", we know the command queue has finished executing WaitForSingleObject(fenceEvent, INFINITE); } // increment fenceValue for next frame fenceValue[frameIndex]++; }
参考链接：
- https://docs.microsoft.com/en-us/windows/win32/direct3d12/directx-12-programming-guide
- http://www.d3dcoder.net/
- https://www.braynzarsoft.net/viewtutorial/q16390-04-directx-12-braynzar-soft-tutorials
- https://developer.nvidia.com/dx12-dos-and-donts
- https://www.3dgep.com/learning-directx-12-1/
- https://gpuopen.com/learn/lets-learn-directx12/
- https://alain.xyz/blog/raw-directx12
- https://www.rastertek.com/tutdx12.html
- https://digitalerr0r.net/2015/08/19/quickstart-directx-12-programming/
- https://walbourn.github.io/getting-started-with-direct3d-12/
- https://docs.aws.amazon.com/lumberyard/latest/userguide/graphics-rendering-directx.html
- http://diligentgraphics.com/diligent-engine/samples/
- https://www.programmersought.com/article/2904113865/
- https://www.tutorialspoint.com/directx/directx_first_hlsl.htm
- http://rbwhitaker.wikidot.com/hlsl-tutorials
- https://digitalerr0r.net/2015/08/19/quickstart-directx-12-programming/
- https://www.ronja-tutorials.com/post/002-hlsl/