1. I'm not sure why you're posting in English here, when there's an English forum over at
en.delphipraxis.net but welcome here anyway.
2. Why don't you declare a pointer to that TRGBType and let that one point to the scanline property? By incremeinting that pointer you can scan 4 bytes forwards then.
Something like this one:
Delphi-Quellcode:
type
TRGBColor = Integer;
var
pFirstByte:^TRGBColor;
MyColor: TRGBColor;
begin
pFirstByte := DWORD(bm1.scanline[0]);
MyColor := pFirstByte^;
inc(pFirstByte); // point to the next color(s)
MyColor := pFirstByte^;