Max size of graphic bitmap?

[Conrad Hoffman]

I want to create some pretty large bitmaps to be sent to a high res printer. I find GRAPHIC BITMAP NEW fails to create a handle at something less than 8000 by 8000. What limit am I running into- memory? Something else? I'd really like to fill a 8x10.5 page at 1200dpi, so 9600 by 12600 would be ideal. That may seem large, but it's pretty common in my photo/graphics world.

[Dave Biggs]

On my pc (1GB of RAM, page size 3GB) this code stopped at 5200 x 5200.

Function PbMain()
 Dim x&, hBmp???
  Do
    Sleep 1
    x = x + 100
    GRAPHIC BITMAP NEW x, x TO hBmp
    If hBmp >0 Then
      GRAPHIC Attach hBmp, 0
      GRAPHIC Bitmap End
      Iterate Loop
    Else 
      Exit loop
    End If
  Loop
 
  MsgBox "Bitmap New failed at "+str$(x)+" x "+str$(x),,"Result"
 
End Function

[Conrad Hoffman]

I didn't go looking for the exact size before, but with your code it's 6200 x 6200. I have 2G of RAM, but the video takes about 0.5, plus XP, leaving a bit under 1G to play with. If a graphic bitmap is 8 bits/color, that's 6200*6200*8*3 = 922560000 bits or 115320000 bytes or 112.6 MB. Is that right (my math is always suspect) or am I missing something else that contributes to size or limitations?

Thanks,
CH

[Michael Mattias]

Maybe you can create multiple smaller bitmaps and just print 'em separately but adjacent?

[Kev Peel]

You are limited by actual graphics (video) memory with DDBs (Device Dependent Bitmap). If you are NOT using GDI calls on the bitmap, allocate it as a DIB (Device Independent Bitmap, or "memory bitmap") and use the APIs DIB functions to manage it. DIBs are handled in RAM, which has a 2GB limit under Win32, so you should be safe.

I think the GRAPHIC statements offered by the compiler use DDBs but you'd have to verify that with PB's support dept.

[Conrad Hoffman]

MCM, that's definitely possible. Some of the things I'm drawing are circular, so I could just mirror the data of a single quad to get the whole thing. For other objects, it's more difficult, but doable.

Kev, it never would have occurred to me that the bitmap was being done in video memory before it got copied for display, but now it makes sense and explains a lot.

Drifting away a bit, when I print using XPRINT statements, is it just like working with a bitmap, that is, can I do anything I want with the pixels, multiple times, overwriting, whatever and nothing is finalized and printed until I issue XPRINT CLOSED?

Thanks,
CH