braynzarsoft-D3D11
07.深度模版
2024-06-12
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0
以下是另一节关于如何实现深度。我们将创建一个深度/模板缓冲区，然后创建一个将其绑定到管道的OM阶段的深度/模板视图。将深度/模板视图绑定到OM阶段将允许它检查渲染目标上每个像素片段的深度值。如果渲染目标上的一个点中有多个像素片段，则将绘制深度值最低（最靠近屏幕）的像素片段，而其他像素片段将被丢弃。
本教程的结果看起来与上一教程没有任何不同，但要在directx中渲染3D场景，需要实现深度/模具缓冲区。
本节的源码：
- https://www.braynzarsoft.net/file/6
- DX11_Lesson_07_Depth_zip.zip
简介
本节我们通过创建深度/模板缓冲区和视图，然后将其绑定到OM阶段来实现3D场景的深度。
深度/模板视图
深度/模板视图的作用是让管道的OM阶段检查渲染目标上的所有像素片段的深度/模板值。像素片段是指有可能被写入屏幕的像素。想象一个球体和一个盒子。球体位于长方体的后面，因此当它们被推送通过渲染管道时，球体中的像素和长方体中的像素都会被放置到渲染目标上。这些像素称为像素片段。
当像素到达OM级时，OM级将像素碎片深度值与已经在该位置的像素碎片进行比较。如果新的像素片段深度值小于已经存在的像素片段，那么已经存在的该像素片段将被丢弃，并且新的像素碎片将保留在渲染目标上。回到球体和长方体。假设先渲染球体。渲染目标上还没有几何体，因此将渲染整个球体。但当长方体的像素到达OM阶段时，OM阶段会比较长方体像素和球体像素的深度值。由于长方体位于球体前面，因此球体的像素片段将被丢弃，长方体的像素片段保留在渲染目标上。绘制完所有几何体后，渲染目标上剩下的像素就是屏幕上显示的像素。
深度视图的模板部分用于高级技术，如镜子，我们稍后将学习。
全局变量声明
这里我们有两个新的接口对象。一种是存储深度/模板视图，另一种是保存深度/模板缓冲区。
ID3D11DepthStencilView* depthStencilView; //深度模板视图
ID3D11Texture2D* depthStencilBuffer; //深度模板缓冲区
现在转到初始化d3d的位置。在创建深度/模版缓冲区之前，我们需要定义它。我们可以通过填写D3D11_TEXTURE2D_DESC来实现这一点，就像填写后台缓冲区一样。这里唯一真正需要提到的是绑定标志和格式，因为我们已经介绍了这个结构。格式为两个变量提供了空间；24位用于深度，8位用于模版。绑定标志表示此纹理将作为深度/模版缓冲区绑定到OM阶段。
//Describe our Depth/Stencil Buffer
D3D11_TEXTURE2D_DESC depthStencilDesc;
depthStencilDesc.Width = Width;
depthStencilDesc.Height = Height;
depthStencilDesc.MipLevels = 1;
depthStencilDesc.ArraySize = 1;
depthStencilDesc.Format = DXGI_FORMAT_D24_UNORM_S8_UINT;
depthStencilDesc.SampleDesc.Count = 1;
depthStencilDesc.SampleDesc.Quality = 0;
depthStencilDesc.Usage = D3D11_USAGE_DEFAULT;
depthStencilDesc.BindFlags = D3D11_BIND_DEPTH_STENCIL;
depthStencilDesc.CPUAccessFlags = 0;
depthStencilDesc.MiscFlags = 0;
创建深度模版视图
现在我们已经定义了深度/模版缓冲区，我们需要创建它。
我们可以使用设备接口的CreateTexture2D方法创建它。
创建深度/模版缓冲区后，我们需要创建将绑定到管道的OM阶段的深度/模版视图。
我们通过从设备接口调用CreateDepthStencilView（）来实现这一点。第一个参数是我们的深度/模版缓冲区描述，第二个参数用于深度/模版状态。我们没有，所以将其设置为NULL。第三个是返回的深度/模版缓冲区。
d3d11Device->CreateTexture2D(&depthStencilDesc, NULL, &depthStencilBuffer);
d3d11Device->CreateDepthStencilView(depthStencilBuffer, NULL, &depthStencilView);
绑定深度模版视图
为了在程序中实现深度，我们需要做的最后一件事是将它绑定到管道的OM阶段。还记得在绑定渲染目标时使用此函数吗？之前我们调用这个函数并将第三个参数设置为NULL，因为我们没有深度/模具视图。我们现在有了一个，所以我们可以将NULL参数更改为我们从上面创建的depthStencilView对象。
d3d11DevCon->OMSetRenderTargets( 1, &renderTargetView, depthStencilView );
深度模版的使用
转到我们创建和描述视口的位置。我们需要告诉管道的OM阶段将像素z值或深度值转换为0到1之间的值，其中0是最接近的值，1是最远的值。
viewport.MinDepth = 0.0f;
viewport.MaxDepth = 1.0f;
清理资源
depthStencilView->Release();
depthStencilBuffer->Release();
清除深度模版视图
我们需要确保的最后一件事是清除每帧的深度/模具视图，就像我们对渲染目标视图所做的那样。
我们通过调用设备上下文接口的ClearDepthStencilView（）方法来实现这一点。第一个值是我们要清除的深度/模版视图，第二个值是枚举类型，一起存储，指定要清除的厚度/模具视图的部分，第四个参数是我们要将深度清除到的值。我们将其设置为1.0f，因为1.0f是任何东西都可以具有的最大深度值。这样可以确保所有对象都绘制在屏幕上。如果我们在这里设置0.0f，则不会在屏幕上绘制任何内容，因为像素片段的所有深度值都将在0.0f和1.0f之间。最后一个参数是我们将模具设置为的值。我们将其设置为0，因为我们没有使用它。
d3d11DevCon->ClearDepthStencilView(depthStencilView, D3D11_CLEAR_DEPTH|D3D11_CLEAR_STENCIL, 1.0f, 0);
代码
main.cpp
//Include and link appropriate libraries and headers//
#pragma comment(lib, "d3d11.lib")
#pragma comment(lib, "d3dx11.lib")
#pragma comment(lib, "d3dx10.lib")
#include <windows.h>
#include <d3d11.h>
#include <d3dx11.h>
#include <d3dx10.h>
#include <xnamath.h>
//Global Declarations - Interfaces//
IDXGISwapChain* SwapChain;
ID3D11Device* d3d11Device;
ID3D11DeviceContext* d3d11DevCon;
ID3D11RenderTargetView* renderTargetView;
ID3D11Buffer* squareIndexBuffer;
ID3D11Buffer* squareVertBuffer;
///////////////**************new**************////////////////////
ID3D11DepthStencilView* depthStencilView;
ID3D11Texture2D* depthStencilBuffer;
///////////////**************new**************////////////////////
ID3D11VertexShader* VS;
ID3D11PixelShader* PS;
ID3D10Blob* VS_Buffer;
ID3D10Blob* PS_Buffer;
ID3D11InputLayout* vertLayout;
//Global Declarations - Others//
LPCTSTR WndClassName = L"firstwindow";
HWND hwnd = NULL;
HRESULT hr;
const int Width = 300;
const int Height = 300;
//Function Prototypes//
bool InitializeDirect3d11App(HINSTANCE hInstance);
void CleanUp();
bool InitScene();
void UpdateScene();
void DrawScene();
bool InitializeWindow(HINSTANCE hInstance,
int ShowWnd,
int width, int height,
bool windowed);
int messageloop();
LRESULT CALLBACK WndProc(HWND hWnd,
UINT msg,
WPARAM wParam,
LPARAM lParam);
//Vertex Structure and Vertex Layout (Input Layout)//
struct Vertex //Overloaded Vertex Structure
{
Vertex(){}
Vertex(float x, float y, float z,
float cr, float cg, float cb, float ca)
: pos(x,y,z), color(cr, cg, cb, ca){}
XMFLOAT3 pos;
XMFLOAT4 color;
};
D3D11_INPUT_ELEMENT_DESC layout[] =
{
{ "POSITION", 0, DXGI_FORMAT_R32G32B32_FLOAT, 0, 0, D3D11_INPUT_PER_VERTEX_DATA, 0 },
{ "COLOR", 0, DXGI_FORMAT_R32G32B32A32_FLOAT, 0, 12, D3D11_INPUT_PER_VERTEX_DATA, 0 },
};
UINT numElements = ARRAYSIZE(layout);
int WINAPI WinMain(HINSTANCE hInstance, //Main windows function
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nShowCmd)
{
if(!InitializeWindow(hInstance, nShowCmd, Width, Height, true))
{
MessageBox(0, L"Window Initialization - Failed",
L"Error", MB_OK);
return 0;
}
if(!InitializeDirect3d11App(hInstance)) //Initialize Direct3D
{
MessageBox(0, L"Direct3D Initialization - Failed",
L"Error", MB_OK);
return 0;
}
if(!InitScene()) //Initialize our scene
{
MessageBox(0, L"Scene Initialization - Failed",
L"Error", MB_OK);
return 0;
}
messageloop();
CleanUp();
return 0;
}
bool InitializeWindow(HINSTANCE hInstance,
int ShowWnd,
int width, int height,
bool windowed)
{
typedef struct _WNDCLASS {
UINT cbSize;
UINT style;
WNDPROC lpfnWndProc;
int cbClsExtra;
int cbWndExtra;
HANDLE hInstance;
HICON hIcon;
HCURSOR hCursor;
HBRUSH hbrBackground;
LPCTSTR lpszMenuName;
LPCTSTR lpszClassName;
} WNDCLASS;
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 = WndClassName;
wc.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
if (!RegisterClassEx(&wc))
{
MessageBox(NULL, L"Error registering class",
L"Error", MB_OK | MB_ICONERROR);
return 1;
}
hwnd = CreateWindowEx(
NULL,
WndClassName,
L"Lesson 4 - Begin Drawing",
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 1;
}
ShowWindow(hwnd, ShowWnd);
UpdateWindow(hwnd);
return true;
}
bool InitializeDirect3d11App(HINSTANCE hInstance)
{
//Describe our SwapChain Buffer
DXGI_MODE_DESC bufferDesc;
ZeroMemory(&bufferDesc, sizeof(DXGI_MODE_DESC));
bufferDesc.Width = Width;
bufferDesc.Height = Height;
bufferDesc.RefreshRate.Numerator = 60;
bufferDesc.RefreshRate.Denominator = 1;
bufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
bufferDesc.ScanlineOrdering = DXGI_MODE_SCANLINE_ORDER_UNSPECIFIED;
bufferDesc.Scaling = DXGI_MODE_SCALING_UNSPECIFIED;
//Describe our SwapChain
DXGI_SWAP_CHAIN_DESC swapChainDesc;
ZeroMemory(&swapChainDesc, sizeof(DXGI_SWAP_CHAIN_DESC));
swapChainDesc.BufferDesc = bufferDesc;
swapChainDesc.SampleDesc.Count = 1;
swapChainDesc.SampleDesc.Quality = 0;
swapChainDesc.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT;
swapChainDesc.BufferCount = 1;
swapChainDesc.OutputWindow = hwnd;
swapChainDesc.Windowed = TRUE;
swapChainDesc.SwapEffect = DXGI_SWAP_EFFECT_DISCARD;
//Create our SwapChain
hr = D3D11CreateDeviceAndSwapChain(NULL, D3D_DRIVER_TYPE_HARDWARE, NULL, NULL, NULL, NULL,
D3D11_SDK_VERSION, &swapChainDesc, &SwapChain, &d3d11Device, NULL, &d3d11DevCon);
//Create our BackBuffer
ID3D11Texture2D* BackBuffer;
hr = SwapChain->GetBuffer( 0, __uuidof( ID3D11Texture2D ), (void**)&BackBuffer );
//Create our Render Target
hr = d3d11Device->CreateRenderTargetView( BackBuffer, NULL, &renderTargetView );
BackBuffer->Release();
///////////////**************new**************////////////////////
//Describe our Depth/Stencil Buffer
D3D11_TEXTURE2D_DESC depthStencilDesc;
depthStencilDesc.Width = Width;
depthStencilDesc.Height = Height;
depthStencilDesc.MipLevels = 1;
depthStencilDesc.ArraySize = 1;
depthStencilDesc.Format = DXGI_FORMAT_D24_UNORM_S8_UINT;
depthStencilDesc.SampleDesc.Count = 1;
depthStencilDesc.SampleDesc.Quality = 0;
depthStencilDesc.Usage = D3D11_USAGE_DEFAULT;
depthStencilDesc.BindFlags = D3D11_BIND_DEPTH_STENCIL;
depthStencilDesc.CPUAccessFlags = 0;
depthStencilDesc.MiscFlags = 0;
//Create the Depth/Stencil View
d3d11Device->CreateTexture2D(&depthStencilDesc, NULL, &depthStencilBuffer);
d3d11Device->CreateDepthStencilView(depthStencilBuffer, NULL, &depthStencilView);
//Set our Render Target
d3d11DevCon->OMSetRenderTargets( 1, &renderTargetView, depthStencilView );
///////////////**************new**************////////////////////
return true;
}
void CleanUp()
{
//Release the COM Objects we created
SwapChain->Release();
d3d11Device->Release();
d3d11DevCon->Release();
renderTargetView->Release();
squareVertBuffer->Release();
squareIndexBuffer->Release();
VS->Release();
PS->Release();
VS_Buffer->Release();
PS_Buffer->Release();
vertLayout->Release();
///////////////**************new**************////////////////////
depthStencilView->Release();
depthStencilBuffer->Release();
///////////////**************new**************////////////////////
}
bool InitScene()
{
//Compile Shaders from shader file
hr = D3DX11CompileFromFile(L"Effects.fx", 0, 0, "VS", "vs_4_0", 0, 0, 0, &VS_Buffer, 0, 0);
hr = D3DX11CompileFromFile(L"Effects.fx", 0, 0, "PS", "ps_4_0", 0, 0, 0, &PS_Buffer, 0, 0);
//Create the Shader Objects
hr = d3d11Device->CreateVertexShader(VS_Buffer->GetBufferPointer(), VS_Buffer->GetBufferSize(), NULL, &VS);
hr = d3d11Device->CreatePixelShader(PS_Buffer->GetBufferPointer(), PS_Buffer->GetBufferSize(), NULL, &PS);
//Set Vertex and Pixel Shaders
d3d11DevCon->VSSetShader(VS, 0, 0);
d3d11DevCon->PSSetShader(PS, 0, 0);
//Create the vertex buffer
Vertex v[] =
{
Vertex( -0.5f, -0.5f, 0.5f, 1.0f, 0.0f, 0.0f, 1.0f ),
Vertex( -0.5f, 0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f ),
Vertex( 0.5f, 0.5f, 0.5f, 0.0f, 0.0f, 1.0f, 1.0f ),
Vertex( 0.5f, -0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 1.0f ),
};
DWORD indices[] = {
0, 1, 2,
0, 2, 3,
};
D3D11_BUFFER_DESC indexBufferDesc;
ZeroMemory( &indexBufferDesc, sizeof(indexBufferDesc) );
indexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
indexBufferDesc.ByteWidth = sizeof(DWORD) * 2 * 3;
indexBufferDesc.BindFlags = D3D11_BIND_INDEX_BUFFER;
indexBufferDesc.CPUAccessFlags = 0;
indexBufferDesc.MiscFlags = 0;
D3D11_SUBRESOURCE_DATA iinitData;
iinitData.pSysMem = indices;
d3d11Device->CreateBuffer(&indexBufferDesc, &iinitData, &squareIndexBuffer);
d3d11DevCon->IASetIndexBuffer( squareIndexBuffer, DXGI_FORMAT_R32_UINT, 0);
D3D11_BUFFER_DESC vertexBufferDesc;
ZeroMemory( &vertexBufferDesc, sizeof(vertexBufferDesc) );
vertexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
vertexBufferDesc.ByteWidth = sizeof( Vertex ) * 4;
vertexBufferDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
vertexBufferDesc.CPUAccessFlags = 0;
vertexBufferDesc.MiscFlags = 0;
D3D11_SUBRESOURCE_DATA vertexBufferData;
ZeroMemory( &vertexBufferData, sizeof(vertexBufferData) );
vertexBufferData.pSysMem = v;
hr = d3d11Device->CreateBuffer( &vertexBufferDesc, &vertexBufferData, &squareVertBuffer);
//Set the vertex buffer
UINT stride = sizeof( Vertex );
UINT offset = 0;
d3d11DevCon->IASetVertexBuffers( 0, 1, &squareVertBuffer, &stride, &offset );
//Create the Input Layout
hr = d3d11Device->CreateInputLayout( layout, numElements, VS_Buffer->GetBufferPointer(),
VS_Buffer->GetBufferSize(), &vertLayout );
//Set the Input Layout
d3d11DevCon->IASetInputLayout( vertLayout );
//Set Primitive Topology
d3d11DevCon->IASetPrimitiveTopology( D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST );
//Create the Viewport
D3D11_VIEWPORT viewport;
ZeroMemory(&viewport, sizeof(D3D11_VIEWPORT));
viewport.TopLeftX = 0;
viewport.TopLeftY = 0;
viewport.Width = Width;
viewport.Height = Height;
///////////////**************new**************////////////////////
viewport.MinDepth = 0.0f;
viewport.MaxDepth = 1.0f;
///////////////**************new**************////////////////////
//Set the Viewport
d3d11DevCon->RSSetViewports(1, &viewport);
return true;
}
void UpdateScene()
{
}
void DrawScene()
{
//Clear our backbuffer
float bgColor[4] = {(0.0f, 0.0f, 0.0f, 0.0f)};
d3d11DevCon->ClearRenderTargetView(renderTargetView, bgColor);
///////////////**************new**************////////////////////
//Refresh the Depth/Stencil view
d3d11DevCon->ClearDepthStencilView(depthStencilView, D3D11_CLEAR_DEPTH|D3D11_CLEAR_STENCIL, 1.0f, 0);
///////////////**************new**************////////////////////
//Draw the triangle
d3d11DevCon->DrawIndexed( 6, 0, 0 );
//Present the backbuffer to the screen
SwapChain->Present(0, 0);
}
int messageloop(){
MSG msg;
ZeroMemory(&msg, sizeof(MSG));
while(true)
{
BOOL PeekMessageL(
LPMSG lpMsg,
HWND hWnd,
UINT wMsgFilterMin,
UINT wMsgFilterMax,
UINT wRemoveMsg
);
if (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
{
if (msg.message == WM_QUIT)
break;
TranslateMessage(&msg);
DispatchMessage(&msg);
}
else{
// run game code
UpdateScene();
DrawScene();
}
}
return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd,
UINT msg,
WPARAM wParam,
LPARAM lParam)
{
switch( msg )
{
case WM_KEYDOWN:
if( wParam == VK_ESCAPE ){
DestroyWindow(hwnd);
}
return 0;
case WM_DESTROY:
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hwnd,
msg,
wParam,
lParam);
}
Effects.fx:
struct VS_OUTPUT
{
float4 Pos : SV_POSITION;
float4 Color : COLOR;
};
VS_OUTPUT VS(float4 inPos : POSITION, float4 inColor : COLOR)
{
VS_OUTPUT output;
output.Pos = inPos;
output.Color = inColor;
return output;
}
float4 PS(VS_OUTPUT input) : SV_TARGET
{
return input.Color;
}
