[Lazarus] opengl

Mattias Gaertner nc-gaertnma at netcologne.de
Wed Mar 5 23:09:51 CET 2008

On Wed, 05 Mar 2008 10:53:01 +0100
Andrea Mauri <andrea.mauri.75 at gmail.com> wrote:

> I will try Envy in order to install the right drivers for my graphics
> card. Anyway I have two more questions:
> 1. TOpenGLControl works properly on my PC (ATI Radeon™ HD 2400 PRO) 
> using GTK but not GTK2, it could be a problem of graphics card
> drivers? Why if I have not installed the correct drivers
> TOpenGLControl works using GTK?
> 2. I have another PC with Ubuntu and I have the same behaviour, 
> TOpenGLControl  works using GTK but not GTK2, how can I check what is
> my graphics card?

The gtk1 implementation uses get_xvisualinfo to retrieve an unspecific
visual. The gtk2 implementation uses glXChooseVisual, which takes a
filter. The default filter is to search for a double buffered, RGBA
visual with stencil buffer. Maybe mesa does not provide such a visual.
I added an exception, when no such visual was found.

Either the defaults must be changed or a fall back mechanism is needed.


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