I'm trying to rotate an image for 309 degrees, and it results in a strange crash:

Quote
#0 SYSTEM_$$_WAITFREE_VAR$PMEMCHUNK_VAR at :0
#1 SYSTEM_$$_SYSFREEMEM_VAR$PFREELISTS$PMEMCHUNK_VAR$$LONGWORD at :0
#2 ?? at :0
#3 FREEMEMNIL(<error reading variable: Attempt to dereference a generic pointer.>) at J:\\Top Down City\EDITORS\Imaging\Source\ImagingUtility.pas:325
#4 FREEIMAGE({WIDTH = 256, HEIGHT = 256, FORMAT = IFA8R8G8B8, SIZE = 262144, BITS = 0x13450070, PALETTE = 0x0}) at J:\\Top Down City\EDITORS\Imaging\Source\Imaging.pas:792
#5 ROTATE45({WIDTH = 256, HEIGHT = 256, FORMAT = IFA8R8G8B8, SIZE = 262144, BITS = 0x13450070, PALETTE = 0x0}, 22, 0x16af720) at J:\\Top Down City\EDITORS\Imaging\Source\Imaging.pas:1970
#6 ROTATEIMAGE({WIDTH = 256, HEIGHT = 256, FORMAT = IFA8R8G8B8, SIZE = 262144, BITS = 0x13450070, PALETTE = 0x0}, 22) at J:\\Top Down City\EDITORS\Imaging\Source\Imaging.pas:2104
#7 MAKEADOOR(292, 0x16afa44) at u_cared.pas:2195
#8 TWND_CAREDITOR__BTN_GENERATEDOORSCLICK(0x17f4c48, <error reading variable>) at u_cared.pas:2348

The crash seems to be depending on which angle i set to rotate about, other angles (343, 326) work well, but 309 degrees seems to be causing an issue.

Image is in this format:

img_door_builder_temp =

record TIMAGEDATA {
  WIDTH = 256,
  HEIGHT = 256,
  FORMAT = IFA8R8G8B8,
  SIZE = 262144,
  BITS = $13450060,
  PALETTE = $0}

Reproducing this is rather easy:

Quote
procedure Twnd_careditor.BitBtn2Click(Sender: TObject);
var
    imgtest: TImageData;
begin

    InitImage(imgtest);

    NewImage(256, 256, IFA8R8G8B8, imgtest);

    RotateImage(imgtest, 309);

    FreeImage(imgtest);

end;

This example seems to show the crash starting at angles 46 and up, but not all ranges seem affected equally:

Quote
procedure Twnd_careditor.BitBtn2Click(Sender: TObject);
var
    imgtest: TImageData;
   i: Integer;
begin

   for i:= 0 to 360 - 1 do begin

      InitImage(imgtest);
       NewImage(256, 256, IFA8R8G8B8, imgtest);
        OutputDebugString(pchar(format('angle %d', [ i ])));
       RotateImage(imgtest, round(i));
       FreeImage(imgtest);

   end;

end;

I think an older imaging version rotated well, maybe i can figure out which one i used in past.

I wish to share this find with galfar and the rest here, it's related to processing 16 bit floating point values:

http://www.fox-toolkit.org/ftp/fasthalffloatconversion.pdf

There is already a pascal implementation of this that i have found:
https://github.com/SAmeis/xplib/blob/master/DeHL/Library/src/Math/DeHL.Math.Half.pas

I hope you find it useful, surely a lookup table based solution with no cpu code branching is a big improvement if you process 16 bit floating point values regularly.