#include "stdafx.h"
#include "example1.h"
#define INITGUID
#include <ddraw.h>

//Image loading and intialization functions//

BOOL bInit=FALSE;

//Global Interface Pointers//

LPDIRECTDRAW7	lpDD=NULL;  //Directdraw object
LPDIRECTDRAWSURFACE7	lpDDSPrimary=NULL;  //Directdraw primary surface
LPDIRECTDRAWCLIPPER	lpClip=NULL;  //Directdraw Clipper
LPDIRECTDRAWSURFACE7	lpBmp=NULL;  //Bitmap Surface

//Windows Class Information//
static char szClass[]="Example1";
static char szCaption[]="First Attempt";

//Error returning String//

const char *ErrStr=NULL;

//Error Messages//

const char Err_Reg_Class[]	="Error Registering Windows Class";
const char Err_Create_Win[]	="Error Creating Window";
const char Err_DirectDrawCreate[]	="DirectDrawCreate Error";
const char Err_Query[]	="QueryInterface Error";
const char Err_Coop[]	="SetCooperativeLevel Failed";
const char Err_CreateClip[]	="CreateClip Failed";
const char Err_CreateSurf[]		="CreateSurf Failed";
const char Err_LoadBMP[]	="Error Loading Image";

//Cleanup Functions to releasr objects

#define SafeRelease(x) if(x){x->Release();x=NULL;}

void Cleanup(void)
{

	//release the interfaces

	SafeRelease(lpBmp);
	SafeRelease(lpDDSPrimary);
	SafeRelease(lpClip);
	SafeRelease(lpDD);

	//dispaly error if one thrown

	if(ErrStr)
		MessageBox(NULL,ErrStr,szCaption,MB_OK);
}



void DrawImage()
{
	//return if not ready to draw at this time
	if(!lpBmp||!bInit)
		return;

		//draw the image

		lpDDSPrimary->Blt(NULL,lpBmp,NULL,DDBLT_WAIT,NULL);
	
}




LRESULT CALLBACK WindowProc(HWND hWnd,unsigned uMsg,WPARAM wParam,LPARAM lParam)
{
	switch(uMsg)
	{
	case WM_PAINT:
			PAINTSTRUCT ps;
			BeginPaint(hWnd,&ps);
			DrawImage();
			EndPaint(hWnd,&ps);
			break;

	case WM_DESTROY:
		Cleanup();
		PostQuitMessage(0);
		break;

	default:
		return DefWindowProc(hWnd,uMsg,wParam,lParam);
	}
	return 0L;
}






LPDIRECTDRAWSURFACE7 bitmap_surface(LPCTSTR file_name)
{
	HDC hdc;
	HBITMAP bit;
	LPDIRECTDRAWSURFACE7 surf;

	//load the interface bitmap

	bit=(HBITMAP)LoadImage(NULL,file_name,IMAGE_BITMAP,0,0,LR_DEFAULTSIZE|LR_LOADFROMFILE);

	if(!bit)  //failed to load, return failure to the caller
		return NULL;

	//get bitmap dimensions

	BITMAP bitmap;
	GetObject(bit,sizeof(BITMAP),&bitmap);
	int surf_width=bitmap.bmWidth;
	int surf_height=bitmap.bmHeight;

	//create surface

	HRESULT ddrval;
	DDSURFACEDESC2 ddsd;
	ZeroMemory(&ddsd,sizeof(ddsd));
	ddsd.dwSize=sizeof(DDSURFACEDESC2);
	ddsd.dwFlags=DDSD_CAPS|DDSD_WIDTH||DDSD_HEIGHT;
	ddsd.ddsCaps.dwCaps=DDSCAPS_OFFSCREENPLAIN||DDSCAPS_SYSTEMMEMORY;
	ddsd.dwWidth=surf_width;
	ddsd.dwHeight=surf_height;

	//attempt to create surface

	ddrval=lpDD->CreateSurface(&ddsd,&surf,NULL);

	//created ok?

	if(ddrval!=DD_OK){
		//no, release bitmap and return failure to the caller

		DeleteObject(bit);
		return NULL;

	}	else	{
		//yes, get a DC for the surface

		surf->GetDC(&hdc);

		//generate a compatible DC

		HDC bit_dc=CreateCompatibleDC(hdc);

		//blit the interface to the surface

		SelectObject(bit_dc,bit);
		BitBlt(hdc,0,0,surf_width,surf_height,bit_dc,0,0,SRCCOPY);

		//release the DCs

		surf->ReleaseDC(hdc);
		DeleteDC(bit_dc);
	}

	//clear bitmap


	DeleteObject(bit);

	//return pointer to caller

	return surf;
}


static  BOOL Init(HINSTANCE hInstance, int nCmdShow)
{
	WNDCLASS	wc;
	HRESULT	hRet;
	DDSURFACEDESC2	ddsd;

	//Setup and register window class

	wc.style=CS_HREDRAW|CS_VREDRAW;
	wc.lpfnWndProc=(WNDPROC) WindowProc;
	wc.cbClsExtra=0;
	wc.cbWndExtra=sizeof(DWORD);
	wc.hInstance=hInstance;
	wc.hIcon=NULL;
	wc.hCursor=LoadCursor(NULL,IDC_ARROW);
	wc.hbrBackground=(HBRUSH)GetStockObject(BLACK_BRUSH);
	wc.lpszMenuName=NULL;
	wc.lpszClassName=szClass;
	if(!RegisterClass(&wc))
	{
		ErrStr=Err_Reg_Class;
		return FALSE;
	}


	//Get Dimensions of Display
	int ScreenWidth=GetSystemMetrics(SM_CXSCREEN);
	int ScreenHeight=GetSystemMetrics(SM_CYSCREEN);

	//Create a Window and Display

	HWND hWnd;


	hWnd=CreateWindow(szClass,szCaption,WS_VISIBLE|WS_POPUP,0,0,ScreenWidth,ScreenHeight,NULL,NULL,hInstance,NULL);
	if(!hWnd)
	{
		ErrStr=Err_Create_Win;
		return FALSE;
	}

	ShowWindow(hWnd,nCmdShow);
	UpdateWindow(hWnd);

	

	//Create the main directdraw object

	hRet=DirectDrawCreateEx(NULL, (LPVOID*)&lpDD, IID_IDirectDraw7, NULL);
	if(hRet!=DD_OK){
		ErrStr=Err_DirectDrawCreate;
		return FALSE;
	}


	//Set our Cooperative level

	hRet=lpDD->SetCooperativeLevel(hWnd,DDSCL_NORMAL);    //SAVED
	if(hRet!=DD_OK)
	{
		ErrStr=Err_Coop;
		return FALSE;
	}

	//Create Clippe

	hRet=lpDD->CreateClipper(NULL,&lpClip,NULL);
	if(hRet!=DD_OK)
	{
		ErrStr=Err_CreateClip;
		return FALSE;
	}
	lpClip->SetHWnd(0,hWnd);


	//Create the Primary Surface

	ZeroMemory(&ddsd,sizeof(ddsd));
	ddsd.dwSize=sizeof(ddsd);
	ddsd.dwFlags=DDSD_CAPS;
	ddsd.ddsCaps.dwCaps=DDSCAPS_PRIMARYSURFACE;
	hRet=lpDD->CreateSurface(&ddsd,&lpDDSPrimary,NULL);
	if(hRet!=DD_OK){
		ErrStr=Err_CreateSurf;
		return FALSE;
	}

	//Set the clipper for the Primary surface

	lpDDSPrimary->SetClipper(lpClip);

	//Flag Initialization as completed

	bInit=TRUE;


	//load the bitmap image

	lpBmp=bitmap_surface("Sample.bmp");

	//display the Image

	DrawImage();

	return TRUE;
}

//Message Loop







int PASCAL WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance,LPSTR lpCmdLine,int nCmdShow)
{
	MSG msg;   //Windows Messaging structure

	//Initialize the application, exit on failure
	if(!Init(hInstance,nCmdShow)){
		Cleanup();
		return FALSE;
	}

	//handle the messagte loop till we exit

	while (GetMessage(&msg,NULL,NULL,NULL)){
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	//exit returning final message

	return(msg.wParam);
}

if(ddrval!=DD_OK){
		//no, release bitmap and return failure to the caller

		DeleteObject(bit);
		return NULL;