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Littlewillie

I can't find the problem.

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I just got started on a small 2D project with DirectDraw. My problem has to due with just displaying my background image. I have displayed it before in different ways, but for some reason I can't get the following to display. I just get a black screen. Here's what I got so far. //system includes #include <windows.h> #include <windowsx.h> #include <ddraw.h> #include <stdio.h> //system defines #define WIN32_LEAN_AND_MEAN //custom includes #include "defines.h" //global definitions #include "bmp.h" //bitmap file reader //globals BOOL ActiveApp; //is this application active? LPDIRECTDRAW lpDirectDrawObject=NULL; //direct draw object LPDIRECTDRAWSURFACE lpPrimary=NULL; //primary surface LPDIRECTDRAWPALETTE lpPrimaryPalette; //its palette LPDIRECTDRAWSURFACE lpSecondary=NULL; //back buffer LPDIRECTDRAWPALETTE lpSecondaryPalette; //its palette LPDIRECTDRAWSURFACE lpBackground=NULL; //background image CBmpFileReader background; //background image //helper functions LPDIRECTDRAWPALETTE CreatePalette(LPDIRECTDRAWSURFACE surface); BOOL InitDirectDraw(HWND hwnd); HWND CreateDefaultWindow(char* name,HINSTANCE hInstance); BOOL LoadImages(){ //load graphics from files to surfaces //get the background image if(!background.load("bckgnd.bmp"))return FALSE; //read from file background.draw(lpBackground); //draw to background surface //set palettes in all surfaces if(!background.setpalette(lpPrimaryPalette))return FALSE; if(!background.setpalette(lpSecondaryPalette))return FALSE; return TRUE; } //LoadImages BOOL ComposeFrame(){ //compose a frame of animation lpSecondary->BltFast(0,0,lpBackground,NULL,DDBLTFAST_NOCOLORKEY|DDBLTFAST_WAIT); return TRUE; } //ComposeFrame BOOL RestoreSurfaces(){ //restore all surfaces BOOL result=TRUE; //primary and secondary surfaces if(FAILED(lpPrimary->Restore()))return FALSE; if(FAILED(lpSecondary->Restore()))return FALSE; //surfaces containing images if(SUCCEEDED(lpBackground->Restore())) //if background restored result=result&&background.draw(lpBackground); //redraw image else return FALSE; return result; } //RestoreSurfaces BOOL PageFlip(){ //return TRUE if page flip succeeds if(lpPrimary->Flip(NULL,DDFLIP_WAIT)==DDERR_SURFACELOST) return RestoreSurfaces(); return TRUE; } //PageFlip BOOL ProcessFrame(){ //process a frame of animation ComposeFrame(); //compose a frame in back surface return PageFlip(); //flip video memory surfaces } //ProcessFrame //message handler (window procedure) long CALLBACK WindowProc(HWND hwnd,UINT message, WPARAM wParam,LPARAM lParam){ switch(message){ case WM_ACTIVATEAPP: ActiveApp=wParam; break; case WM_CREATE: break; case WM_KEYDOWN: //keyboard hit { //get virtual key code and data bits int virtual_code = (int)wParam; int key_state = (int)lParam; //switch on the virtual_key code to be clean switch(virtual_code) { case VK_ESCAPE://if escape key is pressed { DestroyWindow(hwnd);//exit game break; }//end case default: break; }//end switch return(0); }break; case WM_LBUTTONDOWN: //left mouse button down //InputManager.LMouseDown(lParam); //handle it break; case WM_LBUTTONUP: //left mouse button up //if(InputManager.LMouseUp(lParam)) // DestroyWindow(hwnd); break; case WM_MOUSEMOVE: //mouse move //InputManager.MouseMove(lParam); break; case WM_DESTROY: //end of game //ObjectManager.reset(); //clear objects if(lpDirectDrawObject!=NULL){ //if DD object exists if(lpSecondary!=NULL) //if secondary surface exists lpSecondary->Release(); //release secondary surface if(lpPrimary!=NULL) //if primary surface exists lpPrimary->Release(); //release primary surface if(lpBackground!=NULL) //if background exists lpBackground->Release(); //release background lpDirectDrawObject->Release(); //release DD object } ShowCursor(TRUE); //show the mouse cursor PostQuitMessage(0); //and exit break; default: //default window procedure return DefWindowProc(hwnd,message,wParam,lParam); } //switch(message) return 0L; } //WindowProc int WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPrevInstance, LPSTR lpCmdLine,int nCmdShow){ MSG msg; //current message HWND hwnd; //handle to fullscreen window hwnd=CreateDefaultWindow("DungeonQuest",hInstance); if(!hwnd)return FALSE; //set up window ShowWindow(hwnd,nCmdShow); UpdateWindow(hwnd); SetFocus(hwnd); //allow input from keyboard ShowCursor(FALSE); //hide the cursor //init graphics //for(int i=0; i<NUM_SPRITES; i++) //null out sprites // g_pSprite=NULL; BOOL OK=InitDirectDraw(hwnd);//initialize DirectDraw if(OK)OK=LoadImages(); //load images from disk if(!OK){ //bail out if initialization failed DestroyWindow(hwnd); return FALSE; } //message loop while(TRUE) if(PeekMessage(&msg,NULL,0,0,PM_NOREMOVE)){ if(!GetMessage(&msg,NULL,0,0))return msg.wParam; TranslateMessage(&msg); DispatchMessage(&msg); } else if(ActiveApp)ProcessFrame(); else WaitMessage(); } //WinMain I know this is a bit much, but I've troubleshot my problem to the ComposeFrame function. Instead of Blitting to the Secondary surface, I have blitted to the primary, and it worked. I also used the background.draw(lpSecondary) function that I used in loading the image, and that worked. I am wondering what could possibly be the problem with my blitting to the secondary surface? I would appreciate any ideas, thanks.

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bool LoadSecondary()
{ // You could easily use this function to model a generic function that would load any bitmap you like
// into a directdraw surface.
// www.msdn.com has docs for LoadImage() which are good.

HBITMAP hbmp = (HBITMAP)LoadImage(GetModuleHandle(NULL), "yourbmphere.bmp", IMAGE_BITMAP, BLOCKS_BMP_WIDTH,
BLOCKS_BMP_HEIGHT, LR_LOADFROMFILE | LR_CREATEDIBSECTION);

if (!hbmp)
return false;

BITMAP bm;
GetObject(hbmp, sizeof(bm), &bm); // gets me a DC or something like that

DDSURFACEDESC2 ddsd;
DD_INIT_STRUCT(ddsd);

ddsd.dwSize = sizeof(ddsd);
ddsd.dwFlags = DDSD_CAPS | DDSD_HEIGHT | DDSD_WIDTH;
ddsd.ddsCaps.dwCaps = DDSCAPS_OFFSCREENPLAIN | DDSCAPS_SYSTEMMEMORY;
ddsd.dwWidth = bm.bmWidth;
ddsd.dwHeight = bm.bmHeight;
if (g_App.GetDirectDrawObject()->CreateSurface(&ddsd, &m_BuildingBlocksBMP, NULL) != DD_OK)
return false;
DDCopyBitmap(m_BuildingBlocksBMP, hbmp, 0, 0, 0, 0);
DeleteObject(hbmp);

return true;

}



Make sure you clear the ddsd you use AND make absolutely sure you set ddsd.dwSize of, as this can cause a LOT of weird errors.

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I never found out what the problem was, but I fixed it by using the Blt function instead of BltFast. I don't know. Crazy.
Thanks for the reply, I'm using something similar right now to load my bitmap files.

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