Re: Question on gdk-pixbuf

[Nathan Hurst <njh hawthorn csse monash edu au>]

On Sun, 25 Jun 2000, Havoc Pennington wrote:

> Nathan Hurst <njh@hawthorn.csse.monash.edu.au> writes: 
> 
> That's not what I'm asking: "grayscale" typically doesn't mean RGB at all.

It didn't last time I looked.  It should!  Is there anyone on this list
that wants a little project?

I would guess that useful operations would be:

copy from grey to grey
copy from grey to colour(with mapping?)
copy from colour to grey(Luminance?)
paint flat colour in rgb, using grey as alpha channel
copy rgb to rgb using grey as alpha channel

Some combinations of scale, etc.

Incidently, I am wondering whether it would be better to have a single
parameterised function for doing pixbuf -> pixbuf transfer operations,
detecting scaling, change of depth etc. automagically.  It might be a
little slower than a direct call, but would be much easier to document and
grok.  It might also be faster, if it can detect tricks efficiently(such
as noting that a requested scale operation is actually 1:1).

I personally would like some form of clipping, either to svp, or some
other efficient shape code.  If I get time I'll write this myself.

> Implementing gnome-font this way would be pretty stupid. The above is
> just a simple way to do this using existing gdk-pixbuf features.

Yep.  But it would be better to implement gnome-font using the same tools
as gdk_pixbuf so that optimisations in one lead to optimisations in the
other.

njh