[cairo] Frame Buffer and Special Pixel Formats

[Behdad Esfahbod]

On Wed, 2006-11-29 at 01:49 -0500, Klaus Stehle wrote:
> Hallo Cairo,
> 
> There is a need to have a simple cairo frame buffer surface,
> which can handle all that special pixel formats like
> 2-byte-RGB16_565, 3-byte-RGB24_888 etc. etc.
> because a lot of graphic adapters require such odd formats.
> 
> Ok. There is the cairo-image-surface. But I read in the source
> code things like this:
> 
>      cairoint.h:
>      we do not plan on always guaranteeing that cairo will be able
>      to draw to these formats.
> 
>      cairo-image-surface.c:
>      We don't really want to advertise a cairo image surface that
>      supports any possible format.
> 
> 
> Now the question: What are the real reasons behind those
> "we don't want" or "we do not plan" etc.?

My understanding is that we don't want to clutter the image-backend API.
For framebuffers, I think the idea is to use the directfb backend.  That
probably supports a variety of formats already.

behdad


> The curious thing is that a lot of the programming work is already
> done for these formats in the pixman library.
> 
> Cheers
> Klaus
-- 
behdad
http://behdad.org/

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