From: Isabelle Lafon (isabelle++at++discreet.com)
Date: 10/24/2001 07:50:24
Hy Marcin,
As you've suggested, I 've explicitly disabled texture on my channel
geostate.
I obtain the same result. At the end of the first frame draw pfState
says
texture is OFF but GL_TEXTURE_2D is enable. Looks like performer has a
bug.
Isabelle.
Marcin Romaszewicz wrote:
>
> Performer state management is very lazy, meaning that it tries to make as
> few state changes as possible - it's especially messy when it comes to
> textures, since some hardware must have texturing enabled for things like
> seting texEnv or sending the texture data.
>
> When a texture has been enabled, performer will not disable it until
> another geoset which has it turned off is applied. The reason we do this
> is that if you have two geosets with texturing turned on, we will not turn
> texture off at the end of using one and turn it back on for the second
> one.
>
> Since you are not applying a geostate with no texture, or explicitly
> disabling texture, then performer does not find it necessary to disable
> the GL_TEXTURE_2D. It will do so when you apply a state that necessates
> this, so the fact that texturing is turned on is correct behavior.
>
> However, I'm not really sure why pfState is telling you texture is off
> since pfFlushState should guarantee that performer state matches opengl
> state. What happens if you explicitly disable texture on your channel
> geostate? pfState should tell you it's off and so should OpenGL. Does this
> happen? If not, I think performer has a bug.
>
> -- Marcin
>
> On Tue, 23 Oct 2001, Isabelle Lafon
> wrote:
>
> > Hi,
> >
> > Do I miss something about the pfGeoState::apply and pfTexture::apply
> > behaviour or is this a Performer Bug ?
> >
> > Perhaps someone can explain me what exactly pfTexture::apply does or
> > does not in that case ?
> >
> > I'm using the multiProcess mode PFMP_APPCULLDRAW | PFMP_CULL_DL_DRAW.
> > and I am drawing bins.
> >
> > I have an object with a pfGeoState on it. The pfGeoState has a
> > pfTexture set on it and texture mode on. The pfTexture image pointer
> > is null at the beginning (we use image subloading). There is a preFunc
> > method on the pfGeoState in which the pfTexture::setLoadImage followed
> > by the pfTexture::load is done, if required (if we have a new image
> > buffer ready to use).
> >
> > It happens that the GL_TEXTURE_2D state is still enable at the end of
> > the first frame draw even the pfState says that texture is disable.
> > I was expected that the GL_TEXTURE_2D state would be DISABLE and so
> > coherent with pfState current value.
> >
> > Note that I do a pfFlushState at the end of the frame draw.
> >
> >
> > First frame:
> > ===========
> >
> > - pfGeoState::apply. Perhaps pfTexture::apply doesn't do much here
> > because the image pointer is null. But GL_TEXTURE_2D is enable. That
> > seems OK since the texture mode is on in my pfGeoState.
> > - pfGeoState::preFunc: the image buffer is set on the pfTexture and
> > the pfTexture::load call is issued.
> > - Then the object is drawn.
> > - End of the frame draw: pfFlushState is called. GL_TEXTURE_2D on!
> > - SwapBuffer: Object is visible with the texture image.
> >
> > When performer draw an object with a pfGeoState attach to it, he is
> > doing some pfPushState before applying the pfGeoState and some
> > pfPopState after drawing the object. I can see that in the pfState
> > stack. But at the end of this first frame draw, pfState says texture is
> > disable but GL_TEXTURE_2D is still enable. WHY ?
> >
> >
> > Second frame:
> > ============
> >
> > Now that there is an image pointer and that the texture has been
> > loaded, I suppose that pfGeoState::apply do a bit more when it applies
> > the texture. In the pfGeoState preFunc nothing is done on the
> > texture. And at the end of the frame draw pfState and OpenGL agree
> > that texture is disable.
> >
> >
> >
> > First frame - explicit pfTexture::apply call:
> > =============================================
> >
> > NOW, If I add a pfTexture::apply call in the pfGeoState preFunc, the
> > GL_TEXTURE_2D state is disable at the end of the first frame draw,
> > which is what I was expected in the first place.
> > Why do I need this second call to pfTexture::apply?
> >
> >
> >
> >
> > --
> > Isabelle Lafon Discreet Logic
> > Tel: (514) 954-7157 10 Duke
> > Fax: (514) 393-0110 Montreal (Quebec)
> > isabelle++at++discreet.com Canada, H3C 2L7
> >
-- Isabelle Lafon Discreet Logic Tel: (514) 954-7157 10 Duke Fax: (514) 393-0110 Montreal (Quebec) isabelle++at++discreet.com Canada, H3C 2L7
This archive was generated by hypermail 2b29 : Wed Oct 24 2001 - 07:49:22 PDT