Fast rotate Bitmap

[hosune7845]

Hi.

I need to rotate bitmap in my project.

But rotating speed is too slow to use..

Anyone know how to rotate a bitmap fast?

If can, I want to use TLazIntfImage!

[marcov]

I did it once for 90 degrees you could use http://stackoverflow.com/questions/848025/rotating-bitmaps-in-code

A newer, lazarus compilable version of this code is in http://forum.lazarus.freepascal.org/index.php/topic,30556.msg194612.html#msg194612

but it is not for tlazintfimage, but for an own (included) imagetype.

[hosune7845]

I did it once for 90 degrees you could use http://stackoverflow.com/questions/848025/rotating-bitmaps-in-code

A newer, lazarus compilable version of this code is in http://forum.lazarus.freepascal.org/index.php/topic,30556.msg194612.html#msg194612

but it is not for tlazintfimage, but for an own (included) imagetype.

Thank you.

I find one way, It works on PC, But doesn't work on arm-linux

Here's my code :

Code: Pascal  [Select][+][-]

1. var
2.   tmp: TBitmap;
3.   src, dst: TLazIntfImage;
4.   ImgHandle, ImgMaskHandle: THandle;
5.   i, j, t, u, v: integer;
6. begin
7.   tmp := TBitmap.create;
8.   tmp.Width := Image1.Picture.Bitmap.Height;
9.   tmp.Height := Image1.Picture.Bitmap.Width;
10.   dst := TLazIntfImage.Create(0, 0);
11.   dst.LoadFromBitmap(tmp.Handle, tmp.MaskHandle);
12.   src := TLazIntfImage.Create(0, 0);
13.   src.LoadFromBitmap(Image1.Picture.Bitmap.Handle, Image1.Picture.Bitmap.MaskHandle);
14.   u := Image1.Picture.Bitmap.width - 1;
15.   v := Image1.Picture.Bitmap.height - 1;
16.   for i := 0 to u do begin
17.     t := u - i;
18.     for j := 0 to v do
19.       dst.Colors[j, t] := src.Colors[i, j];
20.   end;
21.   dst.CreateBitmaps(ImgHandle, ImgMaskHandle, false); // The error occurs on here.
22.   tmp.Handle := ImgHandle;
23.   tmp.MaskHandle := ImgMaskHandle;
24.   dst.Free;
25.   Image1.Picture.Bitmap.Assign(tmp);
26.   tmp.Free;
27.   src.Free;    
28.  

The error is "Call by var for arg no. 2 has to match exactly: Got "Longlnt" expected "HBITMAP"

[Thaddy]

If it is for windows use the plgblt api. That is very fast and standard windows.

[jack616]

just a thought;
do you need to actually need to rotate the bitmap - or would just changing the
output co-ordinates work?