D3D常用辅助函数 #DirectX #C++

D3D11Utils.cpp

#include <d3d11.h>
#include <d3dx11.h>
/*
*@brief 创建texture配置
*@param textureDesc 保存Texture配置的对象
*@param width 宽度
*@param height 高度
*/
void createTextureDesc(D3D11_TEXTURE2D_DESC &textureDesc,int width, int height) {
	ZeroMemory(&textureDesc, sizeof(textureDesc));
	textureDesc.Width = width;
	textureDesc.Height = height;
	textureDesc.MipLevels = 1;
	textureDesc.ArraySize = 1;
	textureDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
	textureDesc.SampleDesc.Count = 1;
	textureDesc.Usage = D3D11_USAGE_DEFAULT;
	textureDesc.BindFlags = D3D11_BIND_UNORDERED_ACCESS;
	textureDesc.CPUAccessFlags = 0;
	textureDesc.MiscFlags = D3D11_RESOURCE_MISC_SHARED;
}

/*
*@brief 创建D3D Device
*@param d3dDevice 保存ID3D11Device的对象
*/
void createDevice(ID3D11Device *&d3dDevice) {
	UINT createDeviceFlags = 0;

//#ifdef _DEBUG
//	createDeviceFlags |= D3D11_CREATE_DEVICE_DEBUG ; 
//#endif
	createDeviceFlags |= D3D11_CREATE_DEVICE_BGRA_SUPPORT;

	D3D_FEATURE_LEVEL featureLevel;
	ID3D11DeviceContext*  md3dImmediateContext;//立即执行上下文
	HRESULT  hr = D3D11CreateDevice(
		0,                       //IDXGIAdapter* 默认显示适配器
		D3D_DRIVER_TYPE_HARDWARE,//D3D_DRIVER_TYPE 驱动类型
		0,                       //HMODULE 不使用软件驱动
		createDeviceFlags,
		0,                     //若为nullptr则为默认特性等级，否则需要提供特性等级数组
		0,                     //特性等级数组的元素数目
		D3D11_SDK_VERSION,     //SDK版本
		&d3dDevice,            //输出D3D设备
		&featureLevel,         //输出当前应用D3D特性等级
		&md3dImmediateContext);//输出D3D设备上下文

	if (FAILED(hr))
	{
		OutputDebugStringA("D3D11CreateDevice Failed.");
	}
	if (featureLevel != D3D_FEATURE_LEVEL_11_0)
	{
		OutputDebugStringA("Direct3D FeatureLevel 11 unsupported.");
	}
}

/*
*@brief 保存Texture到文件
*@param d3dDevice Device对象
*@param pTexture2D Texture2D对象
*@param path 以.png结尾的路径
*/
void saveTextureToFile(ID3D11Device *d3dDevice, ID3D11Resource* pTexture2D,LPCSTR path) {
	//应判断格式RGBA还是BGRA，并转换保存为RGBA
	ID3D11DeviceContext *ctx = nullptr;
	d3dDevice->GetImmediateContext(&ctx);
	HRESULT hr = D3DX11SaveTextureToFile(ctx, pTexture2D, D3DX11_IFF_PNG, path);
	if (FAILED(hr))
	{
		OutputDebugStringA("D3DX11SaveTextureToFile failed.");
	}
}

/*
*@brief 读取Texture
*@param d3dDevice Device对象
*@param path 要读取的图像文件路径
*@param pTexture2D Texture2D对象
*/
void loadTextureFromFile(ID3D11Device *d3dDevice,LPCSTR path, ID3D11Texture2D *&pTexture2D) {
	D3DX11_IMAGE_LOAD_INFO loadInfo;
	ZeroMemory(&loadInfo, sizeof(D3DX11_IMAGE_LOAD_INFO));
	loadInfo.BindFlags = D3D11_BIND_SHADER_RESOURCE;
	loadInfo.Format = DXGI_FORMAT_R8G8B8A8_UNORM;
	loadInfo.MipLevels = D3DX11_DEFAULT; //这时会产生最大的mipmaps层。 
	loadInfo.MipFilter = D3DX11_FILTER_LINEAR;

	ID3DX11ThreadPump *pump = NULL;

	HRESULT hr = D3DX11CreateTextureFromFile(d3dDevice, path, &loadInfo, pump, (ID3D11Resource**)&pTexture2D, NULL);
	if (FAILED(hr)) {
		OutputDebugStringA("D3DX11CreateTextureFromFile failed.");
	}
}