Hi, wanted to ask if there is any way to convert an Allegro Bitmap into a wxWidgets wxBitmap.

Essentially I want to print my BITMAP* buffer onto a wxDC.
I found the bitmap struct in Allegro which has a void* dat. wxBitmap has a constructor which takes as a parameter a void* to bitmap data. But I don't think it worked as it crashes with an unhandled exception.

VS2008 error:

Unhandled exception at 0x00556ade in Test3.exe: 0xC0000005: Access violation reading location 0x00000000.

in this function

void DrawBitmap(const wxBitmap &bmp, const wxPoint& pt, bool useMask = false)
        { DoDrawBitmap(bmp, pt.x, pt.y, useMask); }

seems like the dat is null I guess?

Any help appreciated
Otherwise I'll have to change all my code to work with wxBitmaps instead of allegro Bitmaps which I don't exactly look forward to

Hm how can I know what the bitmap representation is of a wxBitmap?
Got rid of the previous error which was a mistake of mine. Now it says that bmp.Ok() failed because its an invalid bitmap which sounds logical.

The constructor I try to use is:

wxBitmap(void* data, int type, int width, int height, int depth = -1)

Creates a bitmap from the given data which is interpreted in platform-dependent manner.

What you were suggesting is copying every pixel from one bitmap to the other in a loop? That would propably not work for me since I want a realtime particle editor and such a big loop in every animation loop would propably bring down my fps to the ground.(Plus I don't know how to write pixels on a wxBitmap)

Is the bitmap data representation in memory same for both libraries?(cant find documentation about it :/) How am I supposed to use the bmp->line? Copy each line of one bmp to the other?

I'm starting to think I might just change the whole code to wxBitmaps after all

(because if I use wxBitmap to load bitmaps then I can't blit them in allegro anymore)

Hm now that I thought about it, is there perhaps a way for allegro to blit on a device context or a panel of wx?
Or can it only blit to/from its own Bitmap structures?

Edit: Hm I looked at the code of another guy on these forums and this function propably does a similar job to what I want. I'll give it a try

void blit_from_allegro_to_wx(BITMAP *src, wxDC *target, int sx, int sy, int dx, int dy, int w, int h)
{
  wxPen pn(wxColour(0,0,0), 1, wxDOT);
  for(int x = 0; x < w; ++x)
  {
    for(int y = 0; y < h; ++y)
    { 
      pn.SetColour(((int **)src->line)[y][x] >> 16, (((int **)src->line)[y][x] >> 8) & 0xF, ((int **)src->line)[y][x] & 0xF);
      // make it active
      target->SetPen(pn);
      target->DrawPoint(dx + x, dy + y);
    }
  }
}

Edit2: Damn this code prints the whole image red. :/
Any idea what the correct shifts are to get the r,g,b information out of a line[y][x] ?

Edit3: WHY!?!?! WHY are allegro bitmaps in BGR format?? grrr took me 2 hours to figure out how it is. Finally it works now.
And the code was wrong after all... Here's the fixed version

void blit_from_allegro_to_wx(BITMAP *src, wxDC *target, int sx, int sy, int dx, int dy, int w, int h)
{
  wxPen pn(wxColour(0,0,0), 1, wxDOT);
  for(int x = 0; x < w; ++x)
  {
    for(int y = 0; y < h; ++y)
    { 
      pn.SetColour((((unsigned long **)src->line)[y][x]) & 0xFF, (((unsigned long **)src->line)[y][x]>> 8) & 0xFF,(((unsigned long **)src->line)[y][x] >> 16));
      // make it active
      target->SetPen(pn);
      target->DrawPoint(dx + x, dy + y);
    }
  }
}

The question remains though on if I can blit on wxDC's.
Because this idea didn't help much. It's way too costly to draw the bitmap each loop pixel for pixel