The code with 24 bit/32 bits bitmaps worked flawlessly either in VMs or from RDP. But the Windows RDP client can be forced to use arbitrary bit depth for color, 24 or 32 bit (in the login window before the connection). And in this case, for 32 bit I started seeing different unexpected effects when drawing bitmaps. From semi-transparent effects to out of sync columns drawing.
Although there's no way to see the depth in the Gnome' gui window, I can detect the bit depth with xwininfo command. When the issue is visible the command xwininfo -root | grep "Depth" shows "32". When everything is ok it's 24.
I suspect that it has something to do with xrdp implementation so I wanted to check this in the VM, but to my surprise there's no reliable way to change the depth to 32 bit in linuxes. All those hints involve manual creating and editing xorg.conf file and warns that there are risks.
Did someone meet such issues before? Should I just see this as a xrdp issue and be sure that lazarus/gtk2 does everything right?
Thanks