OpenGL旋转

#include <windows.h> // Header File For Windows
#include <gl\gl.h> // Header File For The OpenGL32 Library
#include <gl\glu.h> // Header File For The GLu32 Library
#include <gl\glut.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 rtri;
GLfloat rquad;


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


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,100.0f);


glMatrixMode(GL_MODELVIEW);// Select The Modelview Matrix
glLoadIdentity();// Reset The Modelview Matrix
}


int InitGL(GLvoid) // All Setup For OpenGL Goes Here
{
glShadeModel(GL_SMOOTH);// Enable Smooth Shading
glClearColor(0.0f, 0.0f, 0.0f, 0.5f);// Black Background
glClearDepth(1.0f);// Depth Buffer Setup
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
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);
glLoadIdentity();


glTranslatef(-1.5f, 0.0f, -6.0f);
glRotatef(rtri, 0.0f, 1.0f, 0.0f);
glBegin(GL_TRIANGLES);
  glColor3f(1.0f, 0.0f, 0.0f);
  glVertex3f(0.0f, 1.0f, 0.0f);
  glColor3f(0.0f, 1.0f, 0.0f);
  glVertex3f(-1.0f, -1.0f, 0.0);
  glColor3f(0.0f, 0.0f, 1.0f);
  glVertex3f(1.0f, -1.0f, 0.0f);
glEnd();


glLoadIdentity();
glTranslatef(1.5f, 0.0f, -6.0f);
glRotatef(rquad, 1.0f, 0.0f, 0.0f);
glColor3f(1.0f, 1.0f, 0.0f);
glBegin(GL_QUADS);
 glVertex3f(-1.0f, 1.0f ,0.0f);
 glVertex3f(1.0f, 1.0f ,0.0f);
 glVertex3f(1.0f, -1.0f,0.0f);
 glVertex3f(-1.0f,-1.0f, 0.0f);
glEnd();


rquad+=0.2f;
rtri-=1.0f;
return TRUE;// Everything Went OK
}












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
wc.hbrBackground= NULL; // No Background Required For GL
wc.lpszMenuName= NULL; // We Don't Want A Menu
wc.lpszClassName= "OpenGL"; // Set The Class Name


if (!RegisterClass(&wc))// Attempt To Register The Window Class
{
MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}

if (fullscreen)// Attempt Fullscreen Mode?
{
DEVMODE dmScreenSettings;// Device Mode
memset(&dmScreenSettings,0,sizeof(dmScreenSettings));// Makes Sure Memory's Cleared
dmScreenSettings.dmSize=sizeof(dmScreenSettings);// Size Of The Devmode Structure
dmScreenSettings.dmPelsWidth= width; // Selected Screen Width
dmScreenSettings.dmPelsHeight= height; // Selected Screen Height
dmScreenSettings.dmBitsPerPel= bits; // Selected Bits Per Pixel
dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;


// Try To Set Selected Mode And Get Results.  NOTE: CDS_FULLSCREEN Gets Rid Of Start Bar.
if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL)
{
// If The Mode Fails, Offer Two Options.  Quit Or Use Windowed Mode.
if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","NeHe GL",MB_YESNO|MB_ICONEXCLAMATION)==IDYES)
{
fullscreen=FALSE;// Windowed Mode Selected.  Fullscreen = FALSE
}
else
{
// Pop Up A Message Box Letting User Know The Program Is Closing.
MessageBox(NULL,"Program Will Now Close.","ERROR",MB_OK|MB_ICONSTOP);
return FALSE; // Return FALSE
}
}
}


if (fullscreen)// Are We Still In Fullscreen Mode?
{
dwExStyle=WS_EX_APPWINDOW;// Window Extended Style
dwStyle=WS_POPUP;// Windows Style
ShowCursor(FALSE);// Hide Mouse Pointer
}
else
{
dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;// Window Extended Style
dwStyle=WS_OVERLAPPEDWINDOW;// Windows Style
}


AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);// Adjust Window To True Requested Size


// Create The Window
if (!(hWnd=CreateWindowEx(dwExStyle, // Extended Style For The Window
"OpenGL", // Class Name
title, // Window Title
dwStyle | // Defined Window Style
WS_CLIPSIBLINGS |// Required Window Style
WS_CLIPCHILDREN,// Required Window Style
0, 0, // Window Position
WindowRect.right-WindowRect.left,// Calculate Window Width
WindowRect.bottom-WindowRect.top,// Calculate Window Height
NULL, // No Parent Window
NULL, // No Menu
hInstance, // Instance
NULL))) // Dont Pass Anything To WM_CREATE
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


static PIXELFORMATDESCRIPTOR pfd= // pfd Tells Windows How We Want Things To Be
{
sizeof(PIXELFORMATDESCRIPTOR),// Size Of This Pixel Format Descriptor
1, // Version Number
PFD_DRAW_TO_WINDOW |// Format Must Support Window
PFD_SUPPORT_OPENGL |// Format Must Support OpenGL
PFD_DOUBLEBUFFER,// Must Support Double Buffering
PFD_TYPE_RGBA,// Request An RGBA Format
bits, // Select Our Color Depth
0, 0, 0, 0, 0, 0,// Color Bits Ignored
0, // No Alpha Buffer
0, // Shift Bit Ignored
0, // No Accumulation Buffer
0, 0, 0, 0, // Accumulation Bits Ignored
16, // 16Bit Z-Buffer (Depth Buffer)  
0, // No Stencil Buffer
0, // No Auxiliary Buffer
PFD_MAIN_PLANE,// Main Drawing Layer
0, // Reserved
0, 0, 0 // Layer Masks Ignored
};

if (!(hDC=GetDC(hWnd)))// Did We Get A Device Context?
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd)))// Did Windows Find A Matching Pixel Format?
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


if(!SetPixelFormat(hDC,PixelFormat,&pfd))// Are We Able To Set The Pixel Format?
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


if (!(hRC=wglCreateContext(hDC)))// Are We Able To Get A Rendering Context?
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


if(!wglMakeCurrent(hDC,hRC))// Try To Activate The Rendering Context
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


ShowWindow(hWnd,SW_SHOW);// Show The Window
SetForegroundWindow(hWnd);// Slightly Higher Priority
SetFocus(hWnd);// Sets Keyboard Focus To The Window
ReSizeGLScene(width, height);// Set Up Our Perspective GL Screen


if (!InitGL())// Initialize Our Newly Created GL Window
{
KillGLWindow();// Reset The Display
MessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}


return TRUE; // Success
}


LRESULT CALLBACK WndProc( HWNDhWnd, // Handle For This Window
UINT uMsg,// Message For This Window
WPARAM wParam, // Additional Message Information
LPARAM lParam) // Additional Message Information
{
switch (uMsg) // Check For Windows Messages
{
case WM_ACTIVATE:// Watch For Window Activate Message
{
if (!HIWORD(wParam))// Check Minimization State
{
active=TRUE; // Program Is Active
}
else
{
active=FALSE; // Program Is No Longer Active
}


return 0; // Return To The Message Loop
}


case WM_SYSCOMMAND:// Intercept System Commands
{
switch (wParam)// Check System Calls
{
case SC_SCREENSAVE:// Screensaver Trying To Start?
case SC_MONITORPOWER:// Monitor Trying To Enter Powersave?
return 0; // Prevent From Happening
}
break; // Exit
}


case WM_CLOSE:// Did We Receive A Close Message?
{
PostQuitMessage(0);// Send A Quit Message
return 0; // Jump Back
}


case WM_KEYDOWN:// Is A Key Being Held Down?
{
keys[wParam] = TRUE;// If So, Mark It As TRUE
return 0; // Jump Back
}


case WM_KEYUP:// Has A Key Been Released?
{
keys[wParam] = FALSE;// If So, Mark It As FALSE
return 0; // Jump Back
}


case WM_SIZE: // Resize The OpenGL Window
{
ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));  // LoWord=Width, HiWord=Height
return 0; // Jump Back
}
}


// Pass All Unhandled Messages To DefWindowProc
return DefWindowProc(hWnd,uMsg,wParam,lParam);
}


int WINAPI WinMain( HINSTANCEhInstance, // Instance
HINSTANCE hPrevInstance, // Previous Instance
LPSTR lpCmdLine,// Command Line Parameters
int nCmdShow)// Window Show State
{
MSG msg;// Windows Message Structure
BOOL done=FALSE;// Bool Variable To Exit Loop


// Ask The User Which Screen Mode They Prefer
if (MessageBox(NULL,"Would You Like To Run In Fullscreen Mode?", "Start FullScreen?",MB_YESNO|MB_ICONQUESTION)==IDNO)
{
fullscreen=FALSE;// Windowed Mode
}


// Create Our OpenGL Window
if (!CreateGLWindow("NeHe's OpenGL Framework",640,480,16,fullscreen))
{
return 0; // Quit If Window Was Not Created
}


while(!done) // Loop That Runs While done=FALSE
{
if (PeekMessage(&msg,NULL,0,0,PM_REMOVE))// Is There A Message Waiting?
{
if (msg.message==WM_QUIT)// Have We Received A Quit Message?
{
done=TRUE; // If So done=TRUE
}
else // If Not, Deal With Window Messages
{
TranslateMessage(&msg);// Translate The Message
DispatchMessage(&msg);// Dispatch The Message
}
}
else // If There Are No Messages
{
// Draw The Scene.  Watch For ESC Key And Quit Messages From DrawGLScene()
if (active) // Program Active?
{
if (keys[VK_ESCAPE])// Was ESC Pressed?
{
done=TRUE; // ESC Signalled A Quit
}
else // Not Time To Quit, Update Screen
{
DrawGLScene();// Draw The Scene
SwapBuffers(hDC);// Swap Buffers (Double Buffering)
}
}


if (keys[VK_F1])// Is F1 Being Pressed?
{
keys[VK_F1]=FALSE;// If So Make Key FALSE
KillGLWindow();// Kill Our Current Window
fullscreen=!fullscreen;// Toggle Fullscreen / Windowed Mode
// Recreate Our OpenGL Window
if (!CreateGLWindow("NeHe's 第一个多边形程序",640,480,16,fullscreen))
{
return 0; // Quit If Window Was Not Created
}
}
}
}


// Shutdown
KillGLWindow();// Kill The Window
return (msg.wParam);// Exit The Program
}