05.颜色
本课程直接建立在上一课程的基础上。
在这里,我们将在我们的顶点结构中包括四个额外的浮点,它将定义顶点的颜色RGBA。然后,我们将向输入布局添加另一个元素,它将告诉管道中的IA我们的顶点结构具有颜色值。之后,我们修改效果文件以包括顶点颜色。在顶点级别指定颜色时,光栅化阶段(RS)将在每个像素的三角形上插值颜色。我们仍然不会在像素着色器中进行任何计算,因为RS将为我们进行计算。
本节的DEMO下载地址:
- https://www.braynzarsoft.net/file/5
- DX11_Lesson_05_Color!_zip.zip
效果文件
让我们先来看Effect文件,在其中创建顶点和像素着色器。
首先,我们创建一个新的结构。这个结构将是VS的返回类型,也是PS的输入类型。我们这样做是为了可以返回多个类型,因为现在我们有了顶点的位置和颜色,我们需要能够返回的不仅仅是位置。我们在VS中所做的就是将为顶点接收的值向下传递到管道中的下一阶段。颜色值最终将在到达PS之前到达RS,在PS中,顶点颜色将在三角形表面上进行插值,并且在完成颜色插值计算后,每个像素都将被发送到PS,在那里我们所做的就是将像素的颜色值传递到OM,以放在渲染目标(Backbuffer)上。
//参数列表由输入布局决定
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;
}
顶点结构
顶点结构体定义如下:
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;
};
输入布局
现在,我们向输入布局数组添加了一个新元素。这个元素表示前12个字节之后的下一个16个字节将被发送到VS中的第一个COLOR变量。你可能认为这听起来更像是在谈论字节,但这就是输入布局的工作方式。
第一个元素是我们的位置,其格式为DXGI_format_R32B32_FLOAT枚举类型,这为R、G和B分别保留了32位或4个字节。这相当于12个字节。因此,位置元素的偏移量将为0,因为它是数组中的第一个元素。
颜色是第二个,位于位置元素后12个字节。由于颜色使用DXGI_FORMAT_R32B32A32_FLOAT枚举类型作为格式,即16个字节,因此如果我们要将另一个元素添加到输入布局中,则下一个元素必须为第5个参数放置28,因为它位于距离数组开头28个字节的位置。
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 },
};
初始化场景
现在剩下要做的就是在创建缓冲区之前将颜色值添加到顶点数组中。我们把第一个变成了红色,第二个变成了绿色,第三个变成了蓝色!这些颜色将在三角形上插值。
bool InitScene()
Vertex v[] =
{
Vertex( 0.0f, 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 ),
};
像素着色器依旧
float4 PS() : SV_TARGET
{
return float4(0.0f, 0.0f, 1.0f, 1.0f);
}
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* triangleVertBuffer;
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);
///////////////**************new**************////////////////////
//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);
///////////////**************new**************////////////////////
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 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();
//Set our Render Target
d3d11DevCon->OMSetRenderTargets( 1, &renderTargetView, NULL );
return true;
}
void CleanUp()
{
//Release the COM Objects we created
SwapChain->Release();
d3d11Device->Release();
d3d11DevCon->Release();
renderTargetView->Release();
triangleVertBuffer->Release();
VS->Release();
PS->Release();
VS_Buffer->Release();
PS_Buffer->Release();
vertLayout->Release();
}
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[] =
{
///////////////**************new**************////////////////////
Vertex( 0.0f, 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 ),
///////////////**************new**************////////////////////
};
D3D11_BUFFER_DESC vertexBufferDesc;
ZeroMemory( &vertexBufferDesc, sizeof(vertexBufferDesc) );
vertexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
vertexBufferDesc.ByteWidth = sizeof( Vertex ) * 3;
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, &triangleVertBuffer);
//Set the vertex buffer
UINT stride = sizeof( Vertex );
UINT offset = 0;
d3d11DevCon->IASetVertexBuffers( 0, 1, &triangleVertBuffer, &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;
//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);
//Draw the triangle
d3d11DevCon->Draw( 3, 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;
}