Display a bitmap image

I'm New to programming and can create a window but i can't seem to draw up a bitmap. I'm using dev c++ and just need some help please.

Ok..if you have the window, then you have 90% of the code done....

If you just want the bitmap to appear on the window, then load a bitmap into your compiler's resource editor, save it as IDB_BITMAP1 and change your windows procedure like so

Code:

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LRESULT CALLBACK WndProc(HWND hWnd,
                                                UINT msg,
                                                WPARAM wParam,
                                                LPARAM lParam)
{
        HDC hdc,//This is for the device context of your window
                memdc;//This DC will hold reference bitmap
        static HBITMAP hBit;//The actual bitmap
        PAINTSTRUCT ps;//For WS_PAINT
        HGDIOBJ hTemp;//Temp. Hold return of SelectObject
        static SIZE size;//Size of Bitmap


        switch(msg) {
        case WM_CREATE:       
                size.cx = 50;//We want the bitmap to be 50x50
                size.cy = 50;
                hBit = (HBITMAP)LoadImage(GetModuleHandle(NULL),
                        MAKEINTRESOURCE(IDB_BITMAP1),IMAGE_BITMAP,
                        size.cx,size.cy,0);//Load our bitmap
                if(!hBit)SendMessage(hWnd,WM_CLOSE,0,0);//Close if fail       
                break;
                case WM_PAINT:
                hdc = BeginPaint(hWnd,&ps);//Do this at start of paint block
                memdc = CreateCompatibleDC(hdc);//copy the dc
                hTemp = SelectObject(memdc,hBit);//Select bitmap into dc
                BitBlt(hdc,0,0,size.cx,size.cy,memdc,0,0,SRCCOPY);//paint to screen
                SelectObject(memdc,hTemp);//restore the spare dc
                DeleteDC(memdc);//destroy the spare
                EndPaint(hWnd,&ps);//End Painting
                break;

  case WM_CLOSE:
                PostQuitMessage(0);
                break;
  default:
                return DefWindowProc(hWnd, msg, wParam, lParam);
 }

 return 0;
}

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If you want a fool example go to Ken's site here

>>If you want a fool example go to Ken's site <<

Not sure what to make of this, but I love the use of the word 'fool'; I may incorporate it into future descriptions. ;) :D

BTW, I like the use of HGDIOBJ in your example; looks like it sidesteps all that (c++) casting rather nicely. :)

Quote:

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Originally posted by Ken Fitlike
>>If you want a fool example go to Ken's site <<

Not sure what to make of this, but I love the use of the word 'fool'; I may incorporate it into future descriptions. ;) :D

BTW, I like the use of HGDIOBJ in your example; looks like it sidesteps all that (c++) casting rather nicely. :)

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ROFLMFAO!!!!!!

Sorry Ken....I meant FULL but my pre-caffine mind had its own ideas......no Freudian slip I assure you :)...I recommend your site most highly

And if you don't want to use resources...

Code:

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/*my first Windows hack, before learnig about GetObject()...:D*/

bool GetBitmapSize(char *filename, int *width, int *height) {

FILE *image_file = fopen(filename, "rb");

if(image_file == NULL)
 {
  *width = 0, *height = 0;
  return false;
 }

int read = 0;

fseek(image_file, 18, SEEK_SET);

read = fread( &(*width), sizeof(int), 1, image_file);

if(!read)
 {
  fclose(image_file);
  *width = 0, *height = 0;
  return false;
 }

fseek(image_file, 22, SEEK_SET);

read = fread( &(*height), sizeof(int), 1, image_file );

if(!read)
 {
  fclose(image_file);
  *width = 0, *height = 0;
  return false;
 }

fclose(image_file);

return true;
}





 

HBITMAP LoadGraphic( char *file_name, int *width, int *height)
{
  GetBitmapSize(file_name, width, height);
 
  return (HBITMAP)LoadImage(GetModuleHandle(NULL), file_name, IMAGE_BITMAP, *width, *height, LR_LOADFROMFILE );
}

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Code:

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d:\dev-c++\main.cpp: In function `LRESULT WndProc(HWND__ *, unsigned int, unsigned int, long int)':
d:\dev-c++\main.cpp:164: redefinition of `LRESULT WndProc(HWND__ *, unsigned int, unsigned int, long int)'
d:\dev-c++\main.cpp:16: `LRESULT WndProc(HWND__ *, unsigned int, unsigned int, long int)' previously defined here

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I get these errors when compiling with Dev C. I also got an error about IDB_BITMAP1 being undefined, even though it was defined in the resource file. Can anyone explain what I am doing wrong?

Those error messages typically mean you did this:

Code:

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#define IDB_BITMAP1  1002 //..you forgot to put this line here.

void foo() {} //..you probably did this.
void foo();    //..when you meant to do this.

 //....rest of program...

void foo() {
 int i;
 //..etc.
}

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Right on both counts. =) Much thanks indeed!