Erik Thiele wrote:

> "I render into a buffer allocated with malloc. at the end i write
> its content with a ggiPutBox to the graphics card (video-ram).
> in my new design i use an a memory-visual instead of the own
> buffer and do a ggiCrossBlit to a default-visual
> => Speed up by factor 10."
> 
> i cannot believe this.
> i really do not understand why this should be true.
> 
> i thought if i cannot get directbuffer the fastest way
> is use malloced buffer and do ggiPutBox.
> why should the CrossBlit be faster, even though it should
> do EXACTLY the same ?

what about a memory visual using video memory ? It's still
offscreen but bitblit operations should be *much* faster.

Which reminds me of a question I wanted to ask on the list here:
Are there any plans to create a visual like structure which's
only use is for caching a la double buffering or backing graphics ?

We'd like to make use of such a data type in the berlin project
quite extensively but as I heared, the visual structure itself
is too complex to be used for that. We really don't want event
support or anything in this structure, it's just a chunk of (hopefully
video) memory. Then it's GGI's responsability to allocate the memory
either from video (if available) or fall back to malloc. There are a lot
of situations where such offscreen 'drawables' would come very handy,
starting from little animated cursors over backing drawables for
the scene behind transient graphics, ...

Stefan
_______________________________________________________              
              
Stefan Seefeld
Departement de Physique
Universite de Montreal
email: [EMAIL PROTECTED]

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      ...ich hab' noch einen Koffer in Berlin...

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