[ Thread Index |
Date Index
| More lists.liballeg.org/allegro-developers Archives
]
On Jan 8, 2008 10:19 PM, Peter Hull <peterhull90@xxxxxxxxxx> wrote:
> As discussed on hack day it would be good to split off the OpenGL code
> into its own file so it can be used cross-platform
> (http://wiki.allegro.cc/Allegro_Hack_Day/2008_January_5). What's the
> best way to do this? I suggest having aintern_opengl.h and opengl.c,
> and writing an implementation of each of the display's vtable
> functions (in ALLEGRO_DISPLAY_INTERFACE) called _al_gl_<something>,
> e.g. _al_gl_draw_line for the draw_line function.
Having those files sounds good to me. About having shared vtable
entries, that probably needs some further thought. Likely we would
need an ALLEGRO_DISPLAY_OPENGL and ALLEGRO_BITMAP_OPENGL from which
all drivers using OpenGL could "derive", like the current
ALLEGRO_DISPLAY_XGLX and ALLEGRO_BITMAP_XGLX derive from
ALLEGRO_DISPLAY and ALLEGRO_BITMAP. Initially just calling the shared
OpenGL code is probably enough though, right now we only have about 5%
of the OpenGL code contained in AllegroGL. But in the long run it
certainly will be good to have as much as possible shared, like in
AllegroGL.
Also, as I mentioned in the meeting, we have to decide what to do
about OpenGL extensions. Right now I limited it all to OpenGL 1.0, but
we definitely need to use extensions, and also provide them to users
as OpenGL itself doesn't support that. AllegroGL has code to deal with
extensions, and another library mentioned often for this seems to be
GLEW, which we could depend on.