[Lazarus] TOpenGLControl: multisampling not working (Linux/GLX)

[Reimar Grabowski]

On Tue, 26 Feb 2013 06:17:04 +0100
Michalis Kamburelis <michalis.kambi at gmail.com> wrote:

> What is weirder is that I can get multi-sampling on both these systems 
> (both Radeon and NVidia) with a very similar multi-sampling code inside 
> my Castle Game Engine TCastleWindow class (that directly uses GTK and 
> GTKGlExt, without Lazarus TOpenGLControl, to create window with OpenGL 
> context)
GTKGLExt may be the thing making it work. I don't have enough details but searching around the net showed that GTKGLArea does not support multisampling. AFAIR TOpenGLControls code is based on this. 
The lazarus forum post I linked to in another mail showed multisampling did work for the OpenGL examples that come with FPC. Multisampling does work with GTKGLExt as your engine shows. So I still think it is a problem with GDK but that is just a gut feeling.
Perhaps TOpenGLControl can be rewritten to use GTKGLExt following your code if your license permits it. It's a shame that the GTK guys did not get their act together and don't offer a standard way of context creation like virtually every other widgetset does since years.

R.