DirextX编程

开发平台：
Visual C++

TexFiltering.cpp：源码内容
							#include "zfxd3dUtility.h"
#include <stdio.h>
// 自定义顶点结构体
typedef struct tagCUSTOMVERTEX{
	D3DXVECTOR3 position; // The position of the vertex.
	FLOAT tu, tv;    // The color
}CUSTOMVERTEX;
// 自定义顶点格式
#define D3DFVF_CUSTOMVERTEX  D3DFVF_XYZ|D3DFVF_TEX1
typedef enum tagTEXTUREFILTERTYPE{
	SAMPLE_POINT = 0,
	SAMPLE_LINEAR = 1,
	SAMPLE_ANISOTROPIC = 2,
}TEXTUREFILTERTYPE;
// D3D对象接口
IDirect3D9* g_pd3d;
// D3D设备接口
IDirect3DDevice9* g_pd3dDevice;
// 字体
ID3DXFont* g_pFont = NULL;
// 顶点缓冲和纹理接口
IDirect3DVertexBuffer9* g_pVB = NULL;
IDirect3DTexture9* g_pTex = NULL;
// 设备可支持的最大各向异性滤波值
int g_maxAnisotropic;
// 枚举变量，纹理过滤模式
TEXTUREFILTERTYPE g_filtertype = SAMPLE_POINT;
// 布尔变量，是否开启明细纹理过滤功能
bool g_mipmap = false;
// 建立渲染环境和初始化
bool Setup()
{
	// 得到最大的各向异性值
	D3DCAPS9 caps;
	g_pd3dDevice->GetDeviceCaps(&caps);
	g_maxAnisotropic = caps.MaxAnisotropy;
	// 加载纹理
	HRESULT hr;
	hr = D3DXCreateTextureFromFile(g_pd3dDevice, "texture.bmp", &g_pTex);
	if( FAILED(hr))
	{
		MessageBox(0, "Failed to create texture from file", 0, 0);
		return false;
	}
	else
		g_pd3dDevice->SetTexture(0, g_pTex);
	
	
	// 顶点缓冲初始化
	CUSTOMVERTEX vertices[4] = {
		{ D3DXVECTOR3(-100, 0, -100), 0, 0, },
		{ D3DXVECTOR3( 100, 0, -100), 11, 0, },
		{ D3DXVECTOR3(-100, 0,  100), 0, 11, },
		{ D3DXVECTOR3( 100, 0,  100), 11, 11, },
	};
	if( FAILED(g_pd3dDevice->CreateVertexBuffer( 4*sizeof(CUSTOMVERTEX), 0, D3DFVF_CUSTOMVERTEX
		, D3DPOOL_DEFAULT, &g_pVB, NULL)))
		return FALSE;
	void* pData;
	g_pVB->Lock(0, 4*sizeof(CUSTOMVERTEX), (void**)&pData, 0);
	memcpy(pData, vertices, 4*sizeof(CUSTOMVERTEX));
	g_pVB->Unlock();
	
	// 设定渲染状态
	g_pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);
	g_pd3dDevice->SetRenderState(D3DRS_LIGHTING, false);
	
	// 设置投影矩阵
	D3DXMATRIX proj;
	D3DXMatrixPerspectiveFovLH(
			&proj,
			D3DX_PI * 0.25f, // 45 - degree
			1,
			1.0f,
			1000.0f);
	g_pd3dDevice->SetTransform(D3DTS_PROJECTION, &proj);
	return true;
}
bool DrawTextX()
{
	//用于渲染侦FPS
	static int tmLastTime = GetTickCount();
	int tmNow = GetTickCount();
	//用于计算渲染FPS
	static int nFrameCount = 0;
	static int nFPS = 0;
	if(tmNow - tmLastTime > 1000)
	{
		//计算FPS
		tmLastTime = tmNow;
		nFPS = nFrameCount;
		nFrameCount = 0;
	}
	nFrameCount ++;
	char str[500];
	RECT rect;
	rect.left = 10;
	rect.top = 10;
	rect.bottom = rect.top + 30;
	rect.right = rect.left + 360;
	sprintf(str, "Current FPS:%d, please press 1~5 to enable a different texture filtering mode", nFPS);
	g_pFont->DrawTextA(NULL, str, (int)strlen(str), &rect, DT_LEFT|DT_NOCLIP|DT_WORDBREAK, 0xffffff00);
	switch(g_filtertype)
	{
	case SAMPLE_POINT:
		sprintf(str, "filter type: nearest-point sampling");
		break;
	case SAMPLE_LINEAR:
		sprintf(str, "filter type: linear texture filtering");
		break;
	case SAMPLE_ANISOTROPIC:
		sprintf(str, "filter type: anisotropic texture filtering");
		break;
	}
	rect.left = 10;
	rect.top = 50;
	rect.bottom = rect.top + 10;
	rect.right = rect.left + 360;
	g_pFont->DrawTextA(NULL, str, (int)strlen(str), &rect, DT_LEFT|DT_NOCLIP|DT_WORDBREAK, 0xffffff00);
	if(g_mipmap)
		sprintf(str, "mipmap texturing on");
	else
		sprintf(str, "mipmap texturing off");
	rect.left = 10;
	rect.top = 65;
	rect.bottom = rect.top + 10;
	rect.right = rect.left + 360;
	g_pFont->DrawTextA(NULL, str, (int)strlen(str), &rect, DT_LEFT|DT_NOCLIP|DT_WORDBREAK, 0xffffff00);
	return true;
}
bool Display()
{
	// 设定视口矩阵
	float angle  = (3.0f * D3DX_PI) / 2.0f;
	float height = 5.0f;
	D3DXVECTOR3 eyept( cosf(angle) * 50.0f, height, sinf(angle) * 50.0f );
	D3DXVECTOR3 lookAt(0.0f, 0.0f, 0.0f);
	D3DXVECTOR3 up(0.0f, 1.0f, 0.0f);
	D3DXMATRIX view_mat;
	D3DXMatrixLookAtLH(&view_mat, &eyept, &lookAt, &up);
	g_pd3dDevice->SetTransform(D3DTS_VIEW, &view_mat);
	
	// 绘制场景
	g_pd3dDevice->Clear(0, 0, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, 0x00000000, 1.0f, 0);
	g_pd3dDevice->BeginScene();
	// 输出顶点流
	g_pd3dDevice->SetStreamSource(0, g_pVB, 0, sizeof(CUSTOMVERTEX));
	g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
	g_pd3dDevice->DrawPrimitive(D3DPT_TRIANGLESTRIP, 0, 2);
	
	// 在屏幕上写字
	if(g_pFont)
		DrawTextX();
	g_pd3dDevice->EndScene();
	g_pd3dDevice->Present(0, 0, 0, 0);
	return true;
}
bool CleanUp()
{
	SAFE_RELEASE(g_pd3dDevice);
	SAFE_RELEASE(g_pd3d);
	SAFE_RELEASE(g_pTex);
	SAFE_RELEASE(g_pVB);
	return true;
}
int WINAPI WinMain(HINSTANCE hInstance,
				   HINSTANCE prevInstance, 
				   PSTR cmdLine,
				   int showCmd)
{
	// 应用程序初始化
	if(!InitD3DApp(hInstance, true/*true代表窗口模式*/, 
		D3DDEVTYPE_HAL, &g_pd3d, &g_pd3dDevice, "Texture Filtering"/*窗口标题*/, 400, 400))
	{
		MessageBoxW(0, L"应用程序初始化失败", 0, 0);
		return 0;
	}
	// 创建字体
	if(!InitDXFont(g_pd3dDevice, &g_pFont, "Times New Roman"))
		g_pFont = NULL;
	if(!Setup())
	{
		MessageBox(0, "SetUp() failed!", 0, 0);
		return 0;
	}
	// 进入消息循环
	MSG msg;
	ZeroMemory(&msg, sizeof(msg));
	while(msg.message != WM_QUIT)
	{
		if(PeekMessage(&msg, 0, 0, 0, PM_REMOVE))
		{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
		else
		{
			if(!Display())
			{
				MessageBox(0, "Display() failed!", 0, 0);
				return 0;
			}
		}
	}
	CleanUp();
	return 0;
}
// 消息循环函数
LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	static bool bWireFrame = false;
	switch( msg )
	{
	case WM_DESTROY:
		::PostQuitMessage(0);
		break;
	case WM_KEYDOWN:
		if( wParam == VK_ESCAPE )
			::DestroyWindow(hwnd);
		break;
	case WM_CHAR:
		if(wParam == 49)// 数字键1
		{
			// 开启最近点采样
			g_filtertype = SAMPLE_POINT;
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_POINT);
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_POINT);
		}
		else if(wParam == 50)// 数字键2
		{
			// 开启线性纹理采样
			g_filtertype = SAMPLE_LINEAR;
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_LINEAR);
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_LINEAR);
		}
		else if(wParam == 51)// 数字键3
		{
			// 开启各向异性纹理采样
			g_filtertype = SAMPLE_ANISOTROPIC;
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAGFILTER, D3DTEXF_ANISOTROPIC);
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MINFILTER, D3DTEXF_ANISOTROPIC);
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAXANISOTROPY, 4);
		}
		else if(wParam == 52)// 数字键4
		{
			// 开启明细纹理
			g_mipmap = true;
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MIPFILTER, D3DTEXF_LINEAR);
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MAXMIPLEVEL, 1);
		}
		else if(wParam == 53)// 数字键5
		{
			// 禁用明细纹理
			g_mipmap = false;
			g_pd3dDevice->SetSamplerState(0, D3DSAMP_MIPFILTER, D3DTEXF_NONE);
		}
		break;
	}
	return ::DefWindowProc(hwnd, msg, wParam, lParam);
}

						