Help with Direct X and Win32......:D

[incognito]

Ok, I am going to make the part of the code that I am having problems with, Thank you in advance.

/*****************************************************************************
IsoHex5_1.cpp
Ernest S. Pazera
21MAY2000
Start a WIN32 Application Workspace, add in this file
Needs ddraw.lib and dxguid.lib
*****************************************************************************/

//////////////////////////////////////////////////////////////////////////////
//INCLUDES
//////////////////////////////////////////////////////////////////////////////
#define WIN32_LEAN_AND_MEAN  

#include <windows.h>   
#include "ddraw.h"

//////////////////////////////////////////////////////////////////////////////
//DEFINES
//////////////////////////////////////////////////////////////////////////////
//name for our window class
#define WINDOWCLASS "ISOHEX5"
//title of the application
#define WINDOWTITLE "IsoHex 5-1"

//////////////////////////////////////////////////////////////////////////////
//PROTOTYPES
//////////////////////////////////////////////////////////////////////////////
bool Prog_Init();//game data initalizer
void Prog_Loop();//main game loop
void Prog_Done();//game clean up

//enumeration functions
HRESULT WINAPI EnumModesCallbackCount(LPDDSURFACEDESC2 lpDDSurfaceDesc, LPVOID lpContext);
HRESULT WINAPI EnumModesCallbackList(LPDDSURFACEDESC2 lpDDSurfaceDesc,LPVOID lpContext);


//////////////////////////////////////////////////////////////////////////////
//GLOBALS
//////////////////////////////////////////////////////////////////////////////
HINSTANCE hInstMain=NULL;//main application handle
HWND hWndMain=NULL;//handle to our main window
//IDirectDraw7 Pointer
LPDIRECTDRAW7 lpdd=NULL;
//display mode structure
struct DisplayMode
{
	DWORD dwWidth;
	DWORD dwHeight;
	DWORD dwBPP;
};
//display mode enumeration variables
DWORD dwDisplayModeCount=0;
DisplayMode* DisplayModeList=NULL;

//////////////////////////////////////////////////////////////////////////////
//WINDOWPROC
//////////////////////////////////////////////////////////////////////////////
LRESULT CALLBACK TheWindowProc(HWND hwnd,UINT uMsg,WPARAM wParam,LPARAM lParam)
{
	//which message did we get?
	switch(uMsg)
	{
	case WM_KEYDOWN:
		{
			//check for escape key
			if(wParam==VK_ESCAPE)
			{
				DestroyWindow(hWndMain);
			}

			return(0);//handled message
		}break;
	case WM_DESTROY://the window is being destroyed
		{

			//tell the application we are quitting
			PostQuitMessage(0);

			//handled message, so return 0
			return(0);

		}break;
	case WM_PAINT://the window needs repainting
		{
			//a variable needed for painting information
			PAINTSTRUCT ps;
			
			//start painting
			HDC hdc=BeginPaint(hwnd,&ps);

			/////////////////////////////
			//painting code would go here
			/////////////////////////////

			//end painting
			EndPaint(hwnd,&ps);
						
			//handled message, so return 0
			return(0);
		}break;
	}

	//pass along any other message to default message handler
	return(DefWindowProc(hwnd,uMsg,wParam,lParam));
}


//////////////////////////////////////////////////////////////////////////////
//WINMAIN
//////////////////////////////////////////////////////////////////////////////
int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nShowCmd)
{
	//assign instance to global variable
	hInstMain=hInstance;

	//create window class
	WNDCLASSEX wcx;

	//set the size of the structure
	wcx.cbSize=sizeof(WNDCLASSEX);

	//class style
	wcx.style=CS_OWNDC | CS_HREDRAW | CS_VREDRAW | CS_DBLCLKS;

	//window procedure
	wcx.lpfnWndProc=TheWindowProc;

	//class extra
	wcx.cbClsExtra=0;

	//window extra
	wcx.cbWndExtra=0;

	//application handle
	wcx.hInstance=hInstMain;

	//icon
	wcx.hIcon=LoadIcon(NULL,IDI_APPLICATION);

	//cursor
	wcx.hCursor=LoadCursor(NULL,IDC_ARROW);

	//background color
	wcx.hbrBackground=(HBRUSH)GetStockObject(BLACK_BRUSH);

	//menu
	wcx.lpszMenuName=NULL;

	//class name
	wcx.lpszClassName=WINDOWCLASS;

	//small icon
	wcx.hIconSm=NULL;

	//register the window class, return 0 if not successful
	if(!RegisterClassEx(&wcx)) return(0);

	//create main window
	hWndMain=CreateWindowEx(0,WINDOWCLASS,WINDOWTITLE, WS_POPUP | WS_VISIBLE,0,0,320,240,NULL,NULL,hInstMain,NULL);

	//error check
	if(!hWndMain) return(0);

	//if program initialization failed, then return with 0
	if(!Prog_Init()) return(0);

	//message structure
	MSG msg;

	//message pump
	for(;;)	
	{
		//look for a message
		if(PeekMessage(&msg,NULL,0,0,PM_REMOVE))
		{
			//there is a message

			//check that we arent quitting
			if(msg.message==WM_QUIT) break;
			
			//translate message
			TranslateMessage(&msg);

			//dispatch message
			DispatchMessage(&msg);
		}

		//run main game loop
		Prog_Loop();
	}
	
	//clean up program data
	Prog_Done();

	//return the wparam from the WM_QUIT message
	return(msg.wParam);
}

//////////////////////////////////////////////////////////////////////////////
//INITIALIZATION
//////////////////////////////////////////////////////////////////////////////
bool Prog_Init()
{
	//error code 
	HRESULT hr;

	//initialize the dd pointer
	hr=DirectDrawCreateEx(NULL,(void**)&lpdd,IID_IDirectDraw7,NULL);

	//example for error handling
	if(FAILED(hr))
	{
		//initialization failed
		return(false);
	}

	//set the cooperative level
	lpdd->SetCooperativeLevel(hWndMain,DDSCL_FULLSCREEN | DDSCL_EXCLUSIVE | DDSCL_ALLOWREBOOT);

	//enumerate the displaymodes
	dwDisplayModeCount=0;

	lpdd->EnumDisplayModes(0,NULL,NULL,EnumModesCallbackCount);

	DisplayModeList=new DisplayMode[dwDisplayModeCount];
	dwDisplayModeCount=0;

	lpdd->EnumDisplayModes (0,NULL,NULL,EnumModesCallbackList);

	//pick a display mode
	DisplayMode TestMode;
	TestMode.dwWidth=0;
	TestMode.dwHeight=0;
	TestMode.dwBPP=0;
	DWORD index;
	bool found=false;

	for(index=0;(index<dwDisplayModeCount);index++)
	{
		if(DisplayModeList[index].dwBPP==16)
		{
			if(DisplayModeList[index].dwWidth>TestMode.dwWidth)
			{
				TestMode.dwWidth=DisplayModeList[index].dwWidth;
				TestMode.dwHeight=DisplayModeList[index].dwHeight;
				TestMode.dwBPP=DisplayModeList[index].dwBPP;
				found=true;
			}
		}
	}

	if(!found)
	{
		return(false);
	}

	//set the display mode
	hr=lpdd->SetDisplayMode(TestMode.dwWidth,TestMode.dwHeight,TestMode.dwBPP,0,0);

	return(true);//return success
}

//////////////////////////////////////////////////////////////////////////////
//CLEANUP
//////////////////////////////////////////////////////////////////////////////
void Prog_Done()
{
	//clean up the dd pointer
	if(lpdd)
	{
		lpdd->Release();
		lpdd=NULL;
	}

	//get rid of enumeration stuff
	delete [] DisplayModeList;
}

//////////////////////////////////////////////////////////////////////////////
//MAIN GAME LOOP
//////////////////////////////////////////////////////////////////////////////
void Prog_Loop()
{
	///////////////////////////
	//main game logic goes here
	///////////////////////////
}

//enumeration-count
HRESULT WINAPI EnumModesCallbackCount(
  LPDDSURFACEDESC2 lpDDSurfaceDesc,  
  LPVOID lpContext                   
)
{
	//increment the count variable
	dwDisplayModeCount++;

	//continue the enumeration
	return(DDENUMRET_OK);
}

//enumeration-list
HRESULT WINAPI EnumModesCallbackList(
  LPDDSURFACEDESC2 lpDDSurfaceDesc,  
  LPVOID lpContext                   
)
{
	//copy applicable information to the list
	DisplayModeList[dwDisplayModeCount].dwWidth=lpDDSurfaceDesc->dwWidth;
	DisplayModeList[dwDisplayModeCount].dwHeight=lpDDSurfaceDesc->dwHeight;
	DisplayModeList[dwDisplayModeCount].dwBPP=lpDDSurfaceDesc->ddpfPixelFormat.dwRGBBitCount;

	//increment the count variable
	dwDisplayModeCount++;

	//continue the enumeration
	return(DDENUMRET_OK);
}




[b][i] is this like talking directly to your video card or something? Like here.......When this is called 


HRESULT WINAPI EnumModesCallbackCount(
  LPDDSURFACEDESC2 lpDDSurfaceDesc,  
  LPVOID lpContext                   
)
{
	//increment the count variable
	dwDisplayModeCount++;

	//continue the enumeration
	return(DDENUMRET_OK);
}

Is this talking to your video card and "asking" it things? 
Like here.....

HRESULT WINAPI EnumModesCallbackList(
  LPDDSURFACEDESC2 lpDDSurfaceDesc,  
  LPVOID lpContext                   
)
{
	//copy applicable information to the list
	DisplayModeList[dwDisplayModeCount].dwWidth=lpDDSurfaceDesc->dwWidth;
	DisplayModeList[dwDisplayModeCount].dwHeight=lpDDSurfaceDesc->dwHeight;
	DisplayModeList[dwDisplayModeCount].dwBPP=lpDDSurfaceDesc->ddpfPixelFormat.dwRGBBitCount;

	//increment the count variable
	dwDisplayModeCount++;

	//continue the enumeration
	return(DDENUMRET_OK);
}

Is this "talking" to the video card and getting that information through LPDDSURFACEDESC2 lpDDSurfaceDesc or something? 

Ok, if I am not making any sense, I won't blame, I am not sure I am even making sense to myself. Thank you once again.

[jdinger]

It's not getting the info "through" the DDSURFACEDESC2
structure. It's getting the possible display modes from the video
card and putting that data into the DDSURFACEDESC2.

Then it runs through each DDSURFACEDESC2 structure to see if
the a desired display mode is available. If so, it reset the display
mode in DirectDraw to it.