Re: SetBitmapBits fails - why?

Kevin wrote: 
In this code snippet....


void TForm1::DisplayFrame(void)
{

     FindMinMax();

    int i;

    // copy the raw data to the bitmap while applying contrast adjustment
    for(i = 0; i < rows * cols; i++)
    {
          pBitmapPixels[i] = Contrast(pRawPixels[i], PixMin, PixMax) *
0x010101;
     }

     SetBitmapBits(pbitmap, rows * cols * 4, pBitmapPixels);

    Form2->Canvas->Draw(0, 0, pbitmap);

}

occasionally the function SetBitmapBits(...) fails, it returns zero. Anybody
know why?


No, but why are you not checking the return value?
All return values should always be checked.  When
it fails just do it again.

Also, the 4 in "rows * cols * 4" should really be
replaced with something like sizeof(*pbitmap).

--
Regards,
Martin Leese
E-mail: please@xxxxxxxxxxxxxxxxxxxxxxxxxx
Web: http://members.tripod.com/martin_leese/
.

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