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wolfcry044

Rotation speed differs on computers

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wolfcry044    122
I made this pyramid and it rotates. On my computer it rotates and a normal and good speed, same on my wifes computer. I tried it on hers and it works the same. However when I posted the link to it on my forums and others tried it out they told me that it rotates at an extremely fast rate. They said it's just a blur to them. I don't understand why it's doing that. The other stuff I've made seems to do the same thing. Can you help me find what's wrong? Thanks. Here's the code:
#include <windows.h>		// Header File For Windows
//ADDED IN FOR LOADING BMP
#include <stdio.h>			// Header File For Standard Input/Output
//END ADD
#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

//ADDED IN FOR LOADING BMP
GLfloat	xrot;				// X Rotation ( NEW )
GLfloat	yrot;				// Y Rotation ( NEW )
GLfloat	zrot;				// Z Rotation ( NEW )
GLfloat xspeed;				// X Rotation Speed
GLfloat yspeed;				// Y Rotation Speed
GLfloat	z=-5.0f;			// Depth Into The Screen

//Lighting
GLfloat LightAmbient[]=		{ 0.4f, 0.4f, 0.4f, 1.0f };
GLfloat LightDiffuse[]=		{ 1.0f, 1.0f, 1.0f, 1.0f };
GLfloat LightPosition[]=	{ 3.0f, 1.0f, 3.0f, 1.0f };

GLuint	texture[1];			// Storage For One Texture ( NEW )

//END ADD

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

//ADDED IN FOR LOADING BMP
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=FALSE;									// Status Indicator

	AUX_RGBImageRec *TextureImage[1];					// Create Storage Space For The Texture

	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("Data/pyramid.bmp"))
	{
		Status=TRUE;									// Set The Status To TRUE

		glGenTextures(1, &texture[0]);					// Create The Texture

		// Typical Texture Generation Using Data From The Bitmap
		glBindTexture(GL_TEXTURE_2D, texture[0]);
		glTexImage2D(GL_TEXTURE_2D, 0, 3, TextureImage[0]->sizeX, TextureImage[0]->sizeY, 0, GL_RGB, GL_UNSIGNED_BYTE, TextureImage[0]->data);
		glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
		glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
	}

	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
}
//END ADD


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
}

//BEGIN OPENGL SETUP!
int InitGL(GLvoid)										// All Setup For OpenGL Goes Here
{
	//ADDED IN FOR LOADING BMP
	if (!LoadGLTextures())								// Jump To Texture Loading Routine ( NEW )
	{
		return FALSE;									// If Texture Didn't Load Return FALSE
	}
    glEnable(GL_TEXTURE_2D);							// Enable Texture Mapping ( NEW )
	//END ADD
	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
    //Lighting
	glLightfv(GL_LIGHT1, GL_AMBIENT, LightAmbient);		// Setup The Ambient Light
	glLightfv(GL_LIGHT1, GL_DIFFUSE, LightDiffuse);		// Setup The Diffuse Light
	glLightfv(GL_LIGHT1, GL_POSITION,LightPosition);	// Position The Light
	glEnable(GL_LIGHT1);								// Enable Light One
	return TRUE;										// Initialization Went OK
}
//END OPENGL SETUP

//BEGIN DRAW SCENE!
int DrawGLScene(GLvoid)									// Here's Where We Do All The Drawing
{
	glEnable(GL_LIGHTING);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear The Screen And The Depth Buffer
	glLoadIdentity();									// Reset The View
	glTranslatef(0.0f,0.0f,-5.0f);

	glRotatef(xrot,1.0f,0.0f,0.0f);
	glRotatef(yrot,0.0f,1.0f,0.0f);
	glRotatef(zrot,0.0f,0.0f,1.0f);
    
    
	glBindTexture(GL_TEXTURE_2D, texture[0]);

	glBegin(GL_TRIANGLES);	
		//Top
	    glNormal3f( 0.0f, 1.0f, 0.0f);	
		glTexCoord2f(0.4f, 1.3f);
        glVertex3f( 0.0f, 1.0f, 0.0f);		    // Top Of Triangle (Front)
		
		glTexCoord2f(0.0f, 0.0f);
        glVertex3f(-1.0f,-1.0f, 1.0f);			// Left Of Triangle (Front)
		
		glTexCoord2f(1.0f, 0.0f);
		glVertex3f( 1.0f,-1.0f, 1.0f);			// Right Of Triangle (Front)


		//Right
        glNormal3f( 1.0f, 0.0f, 0.0f);
		glTexCoord2f(0.4f, 1.3f);
		glVertex3f( 0.0f, 1.0f, 0.0f);			// Top Of Triangle (Right)
		
		glTexCoord2f(0.0f, 0.0f);
		glVertex3f( 1.0f,-1.0f, 1.0f);			// Left Of Triangle (Right)
		
		glTexCoord2f(1.0f, 0.0f);
		glVertex3f( 1.0f,-1.0f, -1.0f);			// Right Of Triangle (Right)

		//Back
		glNormal3f( 0.0f, 0.0f,-1.0f);	
		glTexCoord2f(0.4f, 1.3f);
		glVertex3f( 0.0f, 1.0f, 0.0f);			// Top Of Triangle (Back)
		
		glTexCoord2f(0.0f, 0.0f);
		glVertex3f( 1.0f,-1.0f, -1.0f);			// Left Of Triangle (Back)
		
		glTexCoord2f(1.0f, 0.0f);
		glVertex3f(-1.0f,-1.0f, -1.0f);			// Right Of Triangle (Back)


		//Left
        glNormal3f(-1.0f, 0.0f, 0.0f);
		glTexCoord2f(0.4f, 1.3f);
		glVertex3f( 0.0f, 1.0f, 0.0f);			// Top Of Triangle (Left)

		glTexCoord2f(0.0f, 0.0f);
	    glVertex3f(-1.0f,-1.0f,-1.0f);			// Left Of Triangle (Left)
		
		glTexCoord2f(1.0f, 0.0f);
		glVertex3f(-1.0f,-1.0f, 1.0f);			// Right Of Triangle (Left)
		glEnd();

	xrot+=0.0f;
	yrot+=0.5f;
	zrot+=0.0f;


	return TRUE;										// Keep Going
}


//END DRAW SCENE

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(	HWND	hWnd,			// 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
		{
//HAS BEEN ALTERED
			if (!HIWORD(wParam))					// Check Minimization State
//End ALTERATION
			{
				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(	HINSTANCE	hInstance,			// 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("UAF Pyramid",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 && !DrawGLScene()) || keys[VK_ESCAPE])	// Active?  Was There A Quit Received?
			{
				done=TRUE;							// ESC or DrawGLScene Signalled A Quit
			}
			else									// Not Time To Quit, Update Screen
			{
				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("UAF Pyramid",640,480,16,fullscreen))
				{
					return 0;						// Quit If Window Was Not Created
				}
			}
		}
	}

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

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CrimsonSun    336
You are incrementing the yrot variable by .5 degrees per frame which means that computers which can process more frames will rotate the pyramid more quickly. The solution is to have the pyramid rotate a constant rate with respect to time. What you need to do is determine how many seconds have elapsed since you rendered your last frame (the exact function calls for this will depend on what platform and API you are using) and multiply it by how many degrees you wish your object to rotate per second. Then use that result in the glRotatef call.

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mjb5791    122
What you basically want to do is to make the rotation time based. Specify your rotation speed as degrees per second or degrees per tick for instance. When you make the call to rotate your triangle, check how much time has elapsed since the last time you rotated the triangle. Use this along with the rotation speed you have set to determine how much of an angle to rotate the triangle for this iteration.

Does that help or do you need a more detailed explanation?

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wolfcry044    122
I understand the concept, but getting it into syntax is frustrating me. I've been studying hard for a while now, but still all this is mind boggling. Any detailed information would be great so I can study it and see how it was done.

Thank you so much!

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zabo    101
you dont know wat frames per second is? thats kinda weird..... what he means is that lets say your computer runs the program at 30 frames per second that means the pyramid will rotate .5 degrees 30 times in one second. still with me? faster computers might run more frames per second lets say a mind boggling 78 frames per second that means the pyramid rotates .5 degrees 78 times in one second which is exceedingly fast get it?

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Feralrath    163
basically you want to control the amount of times the windows updates in a given second.

so you take the current time and subtract the amount of time since the function was last called and compare it to the the number of frames you want. most games run at about 60fps.

the function to get the time in ms on windows is timegettime();

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coderx75    435
Assuming that you are using a Windows platform, you can use QueryPerformanceFrequency and QueryPerformanceCounter (include windows.h). I don't remember the syntax offhand but google should bring up some useful info.

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