I have been learning OpenGL and have made a simple asteroids engine out of one of NEHE's DevCpp base code. It uses GL_LINE_STRIP and GL_LINE_LOOP drawing modes. The physics is based on something I call the average acceleration Verlet. This actually is a proof-of-concept of acceleration Verlet, which is something that some other programmers were having difficulty with. The basic equation is this: x_2 = 2*x_1 - x_0 + a*t^2 which is equivalent to saying x_2 = x_1 + x_1 - x_0 + a*t*t x_0 is the x position at time 0, x_1 is the position at time 0 + dt, and x_2 is the position at 0 + 2*dt. t is the delta time (dt). In a application running at 120 FPS this amounts to t=(1/120) a is acceleration. I think using average acceleration is more accurate, i.e. replace a with (a + a_old)/2.0f To obtain average velocity: v_average = (x_2 - x_1)/t . The advantage of using the acceleration Verlet is you do not need to store any velocity variables and modify them each frame. If there is enough interest I can add more comments. ----------------------------------------------------

/*
 *		This Code Was Created By Jeff Molofee 2000
 *		A HUGE Thanks To Fredric Echols For Cleaning Up
 *		And Optimizing The Base Code, Making It More Flexible!
 *		If You've Found This Code Useful, Please Let Me Know.
 *		Visit My Site At nehe.gamedev.net
 */

#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\glaux.h>		// Header File For The Glaux Library
#include <math.h>

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
bool    thrust=FALSE;       // Acceleration flag ( NEW )
GLfloat	ship_heading=90;		// Angle For The Ship ( NEW )

GLfloat old_ship_location_x=0;  // X_0 Verlet Location
GLfloat old_ship_location_y=0;  // Y_0 Verlet Location
GLfloat ship_location_x=0;      // X_1 Verlet Location
GLfloat ship_location_y=0;      // Y_1 Verlet Location
GLfloat new_ship_location_x=0;  // X_2 Verlet Location
GLfloat new_ship_location_y=0;  // Y_2 Verlet Location

GLfloat ship_adtdt_x=0;        //  Horizontal Acceleration*DT*DT 
GLfloat ship_adtdt_y=0;        //  Vertical Acceleration*DT*DT          
GLfloat old_ship_adtdt_x=0;        //  Old Horizontal Acceleration*DT*DT 
GLfloat old_ship_adtdt_y=0;        //  Old Horizontal Acceleration*DT*DT 

int     glow=0;
int     glow_direction=1;
const float piover180 = 0.0174532925f;
const float ADTDT = 0.0005f;    // This Represents Acceleration Times DT^2
int     max_screen_width=11;        // Maximum Values For Ship X Component
int     max_screen_height=8;       // Maximum Values For Ship Y Component
const float units_for_ship = 80.0f;  // This Is The Value The Ship Will Be Scaled By

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
{    

	if (glow_direction > 0) // Change The Ship's Outlines Red Parameter Up Or Down
	{
	glow++;
	glow++; //  Using glow++; Was Too Slow, So I Added A Second Increment
	if (glow >= 120)
	   glow_direction=-1;
	}
	else
	{
	glow--;
	glow--;
	if (glow <= 1)
	   glow_direction=1;
	}

	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear Screen And Depth Buffer
	glLoadIdentity();									// Reset The Current Modelview Matrix
	glTranslatef(ship_location_x, ship_location_y, -20.0f); // Move Into The Screen 20.0 and Place Ship
	glRotatef(ship_heading-90.0f,0.0f,0.0f,1.0f);	// Rotate The Ship On The Z axis ( NEW )
							
	// This Is Similar To The Old Turtle Graphics Of Logo
	glBegin(GL_LINE_STRIP);		// Start Drawing The Ship's Outline With A Sequence Of Lines

	glColor3f((glow+135.0f)/255.0f,0.0f,0.0f);						//Set Glowing Color
	glVertex3f( 0.0f, 62/units_for_ship, 0.0f);					// First Point Of The Ship
	glVertex3f(-25/units_for_ship,-62/units_for_ship, 0.0f);	// Second Point Of The Ship
	// OpenGL Connects These Two Points With A Line
	glVertex3f(-18/units_for_ship,-56/units_for_ship, 0.0f);	// Third Point Of The Ship

	glVertex3f(-9/units_for_ship,-50/units_for_ship, 0.0f);		// etc.
	glVertex3f(9/units_for_ship,-50/units_for_ship, 0.0f);					
	glVertex3f(18/units_for_ship,-56/units_for_ship, 0.0f);					 
	glVertex3f( 25/units_for_ship,-62/units_for_ship, 0.0f);				
	glVertex3f( 0.0f, 62/units_for_ship, 0.0f);		// Lastly Connect To The First Point Of The Ship
	glEnd();											// Done Drawing The Ship's Outline

	glColor3f(0.0f,0.0f,1.0f);						// Set Ship Window Color To Blue
    glBegin(GL_LINE_LOOP);	                        // Start Drawing The Ship's Window With A Sequence Of Lines
    //GL_LINE_LOOP Is Very Similar To The GL_LINE_STRIP Mode But Draws A Line Back To The Original Point Automatically

	glVertex3f(-14/units_for_ship,-42/units_for_ship, 0.0f);	// Points On Back Side Of Window				
	glVertex3f(-7/units_for_ship,-36/units_for_ship, 0.0f);					
	glVertex3f(7/units_for_ship,-36/units_for_ship, 0.0f);					
	glVertex3f(14/units_for_ship,-42/units_for_ship, 0.0f);					

	glVertex3f(10/units_for_ship,-29/units_for_ship, 0.0f);		//Points On Forward Side Of Window			
	glVertex3f(5/units_for_ship,-21/units_for_ship, 0.0f);					
	glVertex3f(-5/units_for_ship,-21/units_for_ship, 0.0f);					
	glVertex3f(-10/units_for_ship,-29/units_for_ship, 0.0f);					

	glEnd();											// Done Drawing The Ship's Outline

	if (thrust)
	{
        glBegin(GL_LINE_LOOP);								// Start Drawing A Triangle With Lines
		glColor3f(1.0f, (rand()%60)/100.0f + 0.1f, 0.0f);	// Set Thrust Flame Color To Random Value Between Red And Yellow
		glVertex3f(-8/units_for_ship,-55/units_for_ship, 0.0f);	// First Point Of The Triangle
		glVertex3f(8/units_for_ship,-55/units_for_ship, 0.0f);	 // Second Point Of The Triangle
		glVertex3f((-4+rand()%8)/units_for_ship,
		    (-99+rand()%24)/units_for_ship, 0.0f); // Third Point Of The Triangle
		    // The Random Amounts Will Make The Furthest Point Of The Flame
		    // Jump Around The Point (0, -87, 0)

		glEnd();											// Done Drawing The Ship
// Idea For Modification: Have An Array Of 3 To 10 Thrust Triangles And Colors
// Each Frame Draw Them From Oldest To Newest, Each Frame Lowering Their Color Values
// By 10%	
    }

	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
	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
		{
			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(	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


		fullscreen=FALSE;							// Windowed Mode

	// Create Our OpenGL Window
	if (!CreateGLWindow("Kingofthespill Asteroid version of NeHe's Tutorial",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_DOWN])                  // Find Out If We Need To Accelerate Forward
				{
				    thrust=TRUE;
				}
				else
				{
				    thrust=FALSE;
				}

				if (keys[VK_RIGHT])                // Adjust Right Or Left
				{
				    ship_heading-=1.8;
				}
				else if (keys[VK_LEFT])            // The Else Here Makes Turning Right Dominant
				{                                  // That Means If Both Right And Left Are Pressed
				                                   // The Ship Will Turn Right 
				    ship_heading+=1.8;
				}

				if (thrust)
				{                            		// Update Acceleration Component For Verlet Calculation
					ship_adtdt_x = cos(ship_heading*piover180)*ADTDT; //Horizontal Component
				    ship_adtdt_y = sin(ship_heading*piover180)*ADTDT; //Vertical Component
				}
				else
				{
					ship_adtdt_x = 0; //Horizontal Component
				    ship_adtdt_y = 0; //Vertical Componentx
				}

				//Average Acceleration Verlet
				new_ship_location_x = ship_location_x + ship_location_x -  //Horizontal Component
				            old_ship_location_x + (ship_adtdt_x+old_ship_adtdt_x)/2; 
				new_ship_location_y = ship_location_y + ship_location_y -  //Vertical Component
				            old_ship_location_y + (ship_adtdt_y+old_ship_adtdt_y)/2;

				old_ship_adtdt_x=ship_adtdt_x;                // Save Old Acceleration Values
				old_ship_adtdt_y=ship_adtdt_y;

				// This Next Section Handles Saving The Horizontal Location Values And
				// Adjusts For The Ship Going Too Far To The Right Or Left
				if (new_ship_location_x > max_screen_width)     // Too Far To The Right?
				{
				    old_ship_location_x = ship_location_x-max_screen_width-max_screen_width;
				    ship_location_x = new_ship_location_x-max_screen_width-max_screen_width;
				}
				else if (new_ship_location_x < -max_screen_width) // Too Far To The Left?
				{
				    old_ship_location_x = ship_location_x+max_screen_width+max_screen_width;
				    ship_location_x = new_ship_location_x+max_screen_width+max_screen_width;
				}
				else                                            // Ordinary Save Of Horizontal Location Values
				{
				    old_ship_location_x = ship_location_x;
				    ship_location_x = new_ship_location_x;
				}

				// This Next Section Handles Saving The Vertical Location Values And
				// Adjusts For The Ship Going Too Far Up Or Down
				if (new_ship_location_y > max_screen_height)     // Too Far Up?
				{
    				old_ship_location_y = ship_location_y-max_screen_height-max_screen_height;
				    ship_location_y = new_ship_location_y-max_screen_height-max_screen_height;
				}
				else if (new_ship_location_y < -max_screen_height)//Too Far Down?
				{
				    old_ship_location_y = ship_location_y + max_screen_height + max_screen_height;
				    ship_location_y = new_ship_location_y + max_screen_height + max_screen_height;
				}
				else                                              // Ordinary Save Of Vertical Location Values
				{
				    old_ship_location_y = ship_location_y;
				    ship_location_y = new_ship_location_y;
				}
			}
		}
	}

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

[Edited by - Kingofthespill on August 22, 2007 5:17:00 PM]

You should put your code inside code blocks, makes it a bit easier to read through.

Yes, I agree it is not all that readable. I'll get back with something later.

Also if anyone wants to extend this I would be curious to see what can be done with it.

-= edit = -
It is a bit improved with more comments. That's all the time I have for now.


[Edited by - Kingofthespill on August 22, 2007 5:44:28 PM]

Here is a simple game using this engine (for Windows 9x up):


Instructions:
Run over highlighted green targets while avoiding white barriers. Reach as many targets as possible in 100 seconds. A score of 7 or above is quite good.

Controls:
Left - rotate left
Right- rotate right
Down - thrust
Up - half thrust
Esc - exit

Bugs: the collision detection is inaccurate, meeting you REALLY have to run over the highlighted green targets.

Download: www.hevanet.com/bens/verlet_space_game.exe

Pretty good, though you should work some more on collision detection/response and various gameplay features, like what happens when you collide with a wall and so on.