mygl.cpp

我在一位朋写的雪花示范的基础上增加了线程和背景音乐,版权属于原作者.要dirext8的支持,解压后将mygl.src和data目录复制到c:windowssystem下(适用windows98) 如果

/*
  简单的雪花演示
  感谢NEHE的OPENGL程序框架!
*/

#include <windows.h>	// Header File For Windows
#include <mmsystem.h>	// PlaySound()
#include <process.h>
#include <stdio.h>
#include <gl\gl.h>		// Header File For The OpenGL32 Library
#include <gl\glu.h>		// Header File For The GLu32 Library
#include <gl\glaux.h> 	// Header File For The Glaux Library

HDC			hDC=NULL;		// Private GDI Device Context
HGLRC		hRC=NULL;		// Permanent Rendering Context
HWND		hWnd=NULL;		// Holds Our Window Handle
HINSTANCE	hInstance;		// Holds The Instance Of The Application

bool	keys[256];			// Array Used For The Keyboard Routine
bool	active=TRUE;		// Window Active Flag Set To TRUE By Default
bool	fullscreen=TRUE;	// Fullscreen Flag Set To Fullscreen Mode By Default

GLfloat yrot; // Y 旋转

GLfloat LightAmbient[]= { 0.5f, 0.5f, 0.5f, 1.0f }; //环境光参数 ( 新增 )
GLfloat LightDiffuse[]= { 1.0f, 1.0f, 1.0f, 1.0f }; // 漫射光参数 ( 新增 )
GLfloat LightPosition[]= { 0.0f, 0.0f, 2.0f, 1.0f }; // 光源位置 ( 新增 )

#define TEXTURECOUNT 4
#define SNOWCOUNT 1000
char *bmpfile[TEXTURECOUNT]={"Data/2.bmp","Data/3.bmp","Data/4.bmp","Data/5.bmp"};
GLuint texture[TEXTURECOUNT];

struct TSnow
{
	float x,y,z;
	float xrot,yrot,zrot;
	float Dspeed;
	float Rspeed;
	int TextureIndex;
};

TSnow Snow[SNOWCOUNT];

LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);	// Declaration For WndProc

AUX_RGBImageRec *LoadBMP(char *Filename)				// Loads A Bitmap Image
{
	FILE *File=NULL;									// File Handle
	
	if (!Filename)										// Make Sure A Filename Was Given
	{
		return NULL;									// If Not Return NULL
	}
	
	File=fopen(Filename,"r");							// Check To See If The File Exists
	
	if (File)											// Does The File Exist?
	{
		fclose(File);									// Close The Handle
		return auxDIBImageLoad(Filename);				// Load The Bitmap And Return A Pointer
	}
	
	return NULL;										// If Load Failed Return NULL
}

int LoadGLTextures()									// Load Bitmaps And Convert To Textures
{
	int Status;
	AUX_RGBImageRec *TextureImage[1];					// Create Storage Space For The Texture
	glGenTextures(TEXTURECOUNT, &texture[0]);					// Create The Texture
	for(int i=0;i<TEXTURECOUNT;i++)
	{
		Status=FALSE;									// Status Indicator
		memset(TextureImage,0,sizeof(void *)*1);           	// Set The Pointer To NULL
		// Load The Bitmap, Check For Errors, If Bitmap's Not Found Quit
		if (TextureImage[0]=LoadBMP(bmpfile[i]))
		{
			Status=TRUE;									// Set The Status To TRUE
			// 创建线性滤波纹理
			glBindTexture(GL_TEXTURE_2D, texture[i]);
			glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
			glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
			glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data);
		}
		
		if (TextureImage[0])									// If Texture Exists
		{
			if (TextureImage[0]->data)							// If Texture Image Exists
			{
				free(TextureImage[0]->data);					// Free The Texture Image Memory
			}
			
			free(TextureImage[0]);								// Free The Image Structure
		}
	}
	
	return Status;										// Return The Status
}

GLvoid ReSizeGLScene(GLsizei width, GLsizei height)		// Resize And Initialize The GL Window
{
	if (height==0)										// Prevent A Divide By Zero By
	{
		height=1;										// Making Height Equal One
	}
	
	glViewport(0,0,width,height);						// Reset The Current Viewport
	
	glMatrixMode(GL_PROJECTION);						// Select The Projection Matrix
	glLoadIdentity();									// Reset The Projection Matrix
	
	// Calculate The Aspect Ratio Of The Window
	gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,400.0f);
	glMatrixMode(GL_MODELVIEW);							// Select The Modelview Matrix
	glLoadIdentity();									// Reset The Modelview Matrix
}

void InitSnow()
{
	//初始化雪花数组
	srand(GetTickCount());
	for(int i=0;i<SNOWCOUNT;i++)
	{
		Snow[i].TextureIndex=rand()%3;
		Snow[i].x=float(rand()%200-100);
		Snow[i].z=float(rand()%200-100);
		Snow[i].y=100.0f+float(rand()%25);
		Snow[i].xrot=Snow[i].yrot=Snow[i].zrot=0;
		Snow[i].Dspeed=0.01f*(rand()%10+2);
		Snow[i].Rspeed=0.1f*(rand()%10+2);
	}
	
}

int InitGL(GLvoid)										// All Setup For OpenGL Goes Here
{
	if (!LoadGLTextures())								// Jump To Texture Loading Routine ( NEW )
	{
		return FALSE;									// If Texture Didn't Load Return FALSE
	}
	
	glEnable(GL_TEXTURE_2D); // 启用纹理映射( 新增 )
	glShadeModel(GL_SMOOTH);							// Enable Smooth Shading
	glClearColor(0.5f, 0.5f, 0.5f, 0.5f);				// Black Background
	glClearDepth(1.0f);									// Depth Buffer Setup
	//关闭深度测试，否则会影响效果
	//glEnable(GL_DEPTH_TEST);							// Enables Depth Testing
	//glDepthFunc(GL_LEQUAL);								// The Type Of Depth Testing To Do
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);	// Really Nice Perspective Calculations
	
	glLightfv(GL_LIGHT1, GL_AMBIENT, LightAmbient); // 设置环境光
	glLightfv(GL_LIGHT1, GL_DIFFUSE, LightDiffuse); // 设置漫射光
	glLightfv(GL_LIGHT1, GL_POSITION,LightPosition); // 光源位置
	glEnable(GL_LIGHT1); // 启用一号光源
	
	glBlendFunc(GL_SRC_ALPHA,GL_ONE);					// Set The Blending Function For Translucency
	glEnable(GL_BLEND);	

	return TRUE;										// Initialization Went OK
}

int DrawGLScene(GLvoid)									// Here's Where We Do All The Drawing
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear The Screen And The Depth Buffer
	glLoadIdentity();									// Reset The View
	glTranslatef(0.0f,-30.0f,-150.0f);
	glRotatef(yrot,0.0f,1.0f,0.0f);
	glBindTexture(GL_TEXTURE_2D, texture[3]);

	// 白色地面	
	glColor4f(1.0f, 1.0f, 1.0f, 0.5);
	glBegin(GL_QUADS);
	glNormal3f( 0.0f, 1.0f, 0.0f);
	glTexCoord2f(0.0f, 0.0f); glVertex3f( 100.0f, 0.0f,-100.0f);
	glTexCoord2f(1.0f, 0.0f); glVertex3f( 100.0f, 0.0f, 100.0f);
	glTexCoord2f(1.0f, 1.0f); glVertex3f(-100.0f, 0.0f, 100.0f);
	glTexCoord2f(0.0f, 1.0f); glVertex3f(-100.0f, 0.0f,-100.0f);
	glEnd();

	//想要红雪? :-)
	//glColor4f(1.0f, 0.0f, 0.0f, 0.5);
	for(int i=0;i<SNOWCOUNT;i++)
	{
		glLoadIdentity();									// Reset The View
		glTranslatef(0.0f,-30.0f,-150.0f);
		glRotatef(yrot,0.0f,1.0f,0.0f);
		glBindTexture(GL_TEXTURE_2D, texture[Snow[i].TextureIndex]);
		glTranslatef(Snow[i].x,Snow[i].y,Snow[i].z);
		glRotatef(Snow[i].xrot,1.0f,0.0f,0.0f);
		glRotatef(Snow[i].yrot,0.0f,1.0f,0.0f);
		glRotatef(Snow[i].zrot,0.0f,0.0f,1.0f);
		//雪花
		glBegin(GL_QUADS);
		glNormal3f( 0.0f, 1.0f, 0.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, 0.0f, -1.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 0.0f, 1.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 0.0f, 1.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 0.0f,-1.0f);
		glEnd();

		Snow[i].y-=Snow[i].Dspeed;
		if(Snow[i].y<-33)
			Snow[i].y=125.0f;
		Snow[i].xrot+=Snow[i].Rspeed;
		Snow[i].yrot+=Snow[i].Rspeed;
		Snow[i].zrot+=Snow[i].Rspeed;
	}
	
	yrot+=0.2f;
	
	return TRUE;										// Keep Going
}

GLvoid KillGLWindow(GLvoid)								// Properly Kill The Window
{
	if (fullscreen)										// Are We In Fullscreen Mode?
	{
		ChangeDisplaySettings(NULL,0);					// If So Switch Back To The Desktop
		ShowCursor(TRUE);								// Show Mouse Pointer
	}
	
	if (hRC)											// Do We Have A Rendering Context?
	{
		if (!wglMakeCurrent(NULL,NULL))					// Are We Able To Release The DC And RC Contexts?
		{
			MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}
		
		if (!wglDeleteContext(hRC))						// Are We Able To Delete The RC?
		{
			MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		}
		hRC=NULL;										// Set RC To NULL
	}
	
	if (hDC && !ReleaseDC(hWnd,hDC))					// Are We Able To Release The DC
	{
		MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hDC=NULL;										// Set DC To NULL
	}
	
	if (hWnd && !DestroyWindow(hWnd))					// Are We Able To Destroy The Window?
	{
		MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hWnd=NULL;										// Set hWnd To NULL
	}
	
	if (!UnregisterClass("OpenGL",hInstance))			// Are We Able To Unregister Class
	{
		MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
		hInstance=NULL;									// Set hInstance To NULL
	}
}

/*	This Code Creates Our OpenGL Window.  Parameters Are:					*
*	title			- Title To Appear At The Top Of The Window				*
*	width			- Width Of The GL Window Or Fullscreen Mode				*
*	height			- Height Of The GL Window Or Fullscreen Mode			*
*	bits			- Number Of Bits To Use For Color (8/16/24/32)			*
*	fullscreenflag	- Use Fullscreen Mode (TRUE) Or Windowed Mode (FALSE)	*/

BOOL CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag)
{
	GLuint		PixelFormat;			// Holds The Results After Searching For A Match
	WNDCLASS	wc;						// Windows Class Structure
	DWORD		dwExStyle;				// Window Extended Style
	DWORD		dwStyle;				// Window Style
	RECT		WindowRect;				// Grabs Rectangle Upper Left / Lower Right Values
	WindowRect.left=(long)0;			// Set Left Value To 0
	WindowRect.right=(long)width;		// Set Right Value To Requested Width
	WindowRect.top=(long)0;				// Set Top Value To 0
	WindowRect.bottom=(long)height;		// Set Bottom Value To Requested Height
	
	fullscreen=fullscreenflag;			// Set The Global Fullscreen Flag
	
	hInstance			= GetModuleHandle(NULL);				// Grab An Instance For Our Window
	wc.style			= CS_HREDRAW | CS_VREDRAW | CS_OWNDC;	// Redraw On Size, And Own DC For Window.
	wc.lpfnWndProc		= (WNDPROC) WndProc;					// WndProc Handles Messages
	wc.cbClsExtra		= 0;									// No Extra Window Data
	wc.cbWndExtra		= 0;									// No Extra Window Data
	wc.hInstance		= hInstance;							// Set The Instance
	wc.hIcon			= LoadIcon(NULL, IDI_WINLOGO);			// Load The Default Icon
	wc.hCursor			= LoadCursor(NULL, IDC_ARROW);			// Load The Arrow Pointer