I am trying to get a WndProc Mapping solution to work so that I can avoid just making my WndProc static. In addition, a mapping solution is supposed to be great because I don't need to declare variables in my .cpp file, I can do it in my .h file like it should be.

However, this is exactly my problem: if you uncomment lines 3 and 4 of GameManager.cpp and you comment lines 24 and 25 of GameManager.h, the program runs just fine. But, I need it to be the other way around! Instead what happens is the window opens and closes abruptly. Any insight would be greatly appreciated:

*Edit: sorry if the post is too long, I'm new to these forums. If it's too long just let me know and I'll cut out things I *think* are not causing this issue. However, a big reason I left it is so someone can compile it (it should compile and run straight out of the box!).

main.cpp:

#include "GameManager.h"	// Include our GameManager and let it handle everything.
#include <windows.h>
int WINAPI WinMain(	HINSTANCE	hInstance,			// Instance
					HINSTANCE	hPrevInstance,		// Previous Instance
					LPSTR		lpCmdLine,			// Command Line Parameters
					int			nCmdShow)			// Window Show State
{
	GameManager gameManager;
	GameManager *gm = &gameManager;
	return gm->run();
}

GameManager.h:

#ifndef GAMEMANAGER_H
#define GAMEMANAGER_H

#pragma comment(lib, "opengl32.lib")
#pragma comment(lib, "glu32.lib")

#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

class GameManager
{
public:
	GameManager();
	~GameManager();
	int run();
private:
	HDC			hDC;		// Private GDI Device Context
	HGLRC		hRC;		// Permanent Rendering Context
	HWND		hWnd;		// Holds Our Window Handle
	HINSTANCE	hInstance;		// Holds The Instance Of The Application

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

	GLfloat	rtri;				// Angle For The Triangle ( NEW )
	GLfloat	rquad;				// Angle For The Quad ( NEW )

	virtual LRESULT	CALLBACK MsgProc(HWND, UINT, WPARAM, LPARAM);	// Declaration For WndProc
	static LRESULT	CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);	// Declaration For WndProc
	GLvoid ReSizeGLScene(GLsizei width, GLsizei height);
	int InitGL(GLvoid);
	int DrawGLScene(GLvoid);
	GLvoid KillGLWindow(GLvoid);
	BOOL CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag);

};
#endif

And the biggie, GameManger.cpp:

#include "GameManager.h"

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

GameManager::GameManager()
{
	active = true;		// Window Active Flag Set To TRUE By Default
	fullscreen = false;	// Fullscreen Flag Set To Fullscreen Mode By Default

	hDC=NULL;
	hRC=NULL;
	hWnd=NULL;
}
GameManager::~GameManager()
{

}
int GameManager::run()
{
	MSG		msg;									// Windows Message Structure
	BOOL	done=FALSE;								// Bool Variable To Exit Loop

	fullscreen=FALSE;							// Windowed Mode

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

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

GLvoid GameManager::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 GameManager::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 GameManager::DrawGLScene(GLvoid)									// Here's Where We Do All The Drawing
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear Screen And Depth Buffer
	glLoadIdentity();									// Reset The Current Modelview Matrix
	glTranslatef(-1.5f,0.0f,-6.0f);						// Move Left 1.5 Units And Into The Screen 6.0
	glRotatef(rtri,0.0f,1.0f,0.0f);						// Rotate The Triangle On The Y axis ( NEW )
	glBegin(GL_TRIANGLES);								// Start Drawing A Triangle
		glColor3f(1.0f,0.0f,0.0f);						// Set Top Point Of Triangle To Red
		glVertex3f( 0.0f, 1.0f, 0.0f);					// First Point Of The Triangle
		glColor3f(0.0f,1.0f,0.0f);						// Set Left Point Of Triangle To Green
		glVertex3f(-1.0f,-1.0f, 0.0f);					// Second Point Of The Triangle
		glColor3f(0.0f,0.0f,1.0f);						// Set Right Point Of Triangle To Blue
		glVertex3f( 1.0f,-1.0f, 0.0f);					// Third Point Of The Triangle
	glEnd();											// Done Drawing The Triangle
	glLoadIdentity();									// Reset The Current Modelview Matrix
	glTranslatef(1.5f,0.0f,-6.0f);						// Move Right 1.5 Units And Into The Screen 6.0
	glRotatef(rquad,1.0f,0.0f,0.0f);					// Rotate The Quad On The X axis ( NEW )
	glColor3f(0.5f,0.5f,1.0f);							// Set The Color To Blue One Time Only
	glBegin(GL_QUADS);									// Draw A Quad
		glVertex3f(-1.0f, 1.0f, 0.0f);					// Top Left
		glVertex3f( 1.0f, 1.0f, 0.0f);					// Top Right
		glVertex3f( 1.0f,-1.0f, 0.0f);					// Bottom Right
		glVertex3f(-1.0f,-1.0f, 0.0f);					// Bottom Left
	glEnd();											// Done Drawing The Quad
	rtri+=0.2f;											// Increase The Rotation Variable For The Triangle ( NEW )
	rquad-=0.15f;										// Decrease The Rotation Variable For The Quad ( NEW )
	return TRUE;										// Keep Going
}

GLvoid GameManager::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 GameManager::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
	}

	SetWindowLongPtr(hWnd, GWLP_USERDATA, (long)this);
	
	ShowWindow(hWnd,SW_SHOW);						// Show The Window
	UpdateWindow(hWnd);
	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 GameManager::MsgProc(	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 1;								// 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 1;							// Prevent From Happening
			}
			break;									// Exit
		}

		case WM_CLOSE:								// Did We Receive A Close Message?
		{
			PostQuitMessage(0);						// Send A Quit Message
			return 1;								// Jump Back
		}

		case WM_KEYDOWN:							// Is A Key Being Held Down?
		{
			keys[wParam] = TRUE;					// If So, Mark It As TRUE
			return 1;								// Jump Back
		}

		case WM_KEYUP:								// Has A Key Been Released?
		{
			keys[wParam] = FALSE;					// If So, Mark It As FALSE
			return 1;								// Jump Back
		}

		case WM_SIZE:								// Resize The OpenGL Window
		{
//			ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));  // LoWord=Width, HiWord=Height
			return 1;								// Jump Back
		}
	}

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


LRESULT CALLBACK GameManager::WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam) {    
    // Recover the pointer to our class, don't forget to type cast it back

    GameManager* winptr = (GameManager*)GetWindowLongPtr(hwnd, GWLP_USERDATA);
    // Check if the pointer is NULL and call the Default WndProc

    if (winptr == NULL)
	{
        return DefWindowProc(hwnd, message, wParam, lParam);
    } else
	{
        // Call the Message Handler for my class (MsgProc in my case)
        return winptr->MsgProc(hwnd, message, wParam, lParam); 
    }
}

Edited 7 Years Ago by dalcocer: n/a

Looking for something unrelated and found your unresolved issue. Replying in case someone else bumps into it, or you still have the issue from many months ago. Essentially, the problem is where you are declaring your variables.
In the GameManager.h, you are declaring them inside of the private member of the class GameManager.
In the GameManager.cpp you are declaring them outside of the GameManager class in a Global scope.

In order to fix you problem, you must consider how you want these variables implemented. Should they be inside of the class, or should they be Global variables as you have them now?

If you are planning to continue using them as globals, declare them on line 11 in your GameManager.h

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

bool keys[256]; // Array Used For The Keyboard Routine
bool active; // Window Active Flag Set To TRUE By Default
 
class GameManager
{

However, this is not the proper solution. What you really need to do, is to create 'helper' functions inside of your GameManager private class, then use your GameManager handle to call the helper function, to change/retrieve the variables whenever you need them. ie:

//in your .h
private:
void switch_active();
bool get_active();
void flip_key(int index);
bool get_key(int index);
//in your .cpp
 void GameManager::switch_active(){ //Change the private
  active = !active;
}

 bool GameManager::get_active(){
  return active;
}
void GameManager::flip_key(int index){
 key[index] = !key[index];
}
bool GameManager::get_key(int index){
 return key[index];
}

bool temp_key = get_key(25);

As for a long post, yes, way to long. Only need the class GameManager in your .h and the place where you are declaring it in your .cpp and where you are using it in your code. No fun when the scroll button is 3/8's of an inch

This article has been dead for over six months. Start a new discussion instead.