[SDL] Joystick

Matthias matthias at zislers.de
Tue Jul 16 13:49:01 PDT 2002

--- David Olofson <david.olofson at reologica.se> wrote:

> Then, what about applications that should work with
> or without OpenGL?

The main thrust behind OpenGL for paragui is in 3D
apps, in which case you probably don't want a
> > glSDL, or at least parts of it, would come in
> >for internal library use, so that the 2D code in
> >paragui thinks it's still dealing with regular 2D
> >and doesn't have to be rewritten.  If we scavenged
> >parts of the glSDL code, I'm sure we could have a
> >native OpenGL renderer up fairly easily, since
> glSDL
> >has to do most of what's required I'm guessing.
> Well, it handles tiling of large textures and that
> sort of stuff...
> Works for SFont surfaces, but someone (me!? ;-) has
> to implement
> 2D tiling as well, to handle surfaces that are too
> tall *and* too
> high for the OpenGL setup at hand.

This is the stuff that the OpenGL backend has to
present to the rest of paragui so that it can
transparently (to paragui) support OpenGL without
changing the rest of the source.

> BTW, I'm working some on glSDL-0.4 now. Implemented
> blits from
> and within the screen, and locking/direct rendering
> emulation,
> but it isn't working properly yet.
> Speaking of which, I'm considering a "Dual
> Rendering" mode for
> applications that for some strange reason can't stay
> away from
> reading the screen. The idea is basically to s/w
> render into
> the screen shadow surface in parallel with the
> OpenGL rendering,
> instead of using glReadPixels(). It would be very
> inefficient
> compared to applications doing things the right way,
> but I'm
> quite sure it can be a *lot* faster than reading the
> whole
> OpenGL screen every time the screen surface is
> locked...
> Another idea is to *automatically* activate Dual
> Rendering for
> applications that do these OpenGL unfriendly things
> (like
> locking the screen.) Just activate it as soon as a
> "violation"
> is detected, and disable it again if no further
> nasty
> operations are performed for a certain number of
> frames.

Doesn't the program have to specifically request an
OpenGL mode in glSDL, or is it your intention that the
user selects it without the program's knowledge (as in
the backend, dga, x11, fbcon, etc...)

> //David

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