Re: Canvas shortcomings

[Owen Taylor <otaylor redhat com>]

Lauris Kaplinski <lauris ximian com> writes:

> Hello!
> 
> Unreachable goal IMHO :(
> I have not yet find a way to make a graphic API, that:
> 1) has reasonable speed and quality
> 2) can be used for both interactive and output graphics
> 3) has single, consistent API
> 
> If anybody knows the solution, I would be very interested.

Well, I think you have to define the parameter space a bit for
"reasonable speed and quality". If you want perfect glyph positioning
at all resolutions and PDF-1.4 compositing, then you probably aren't
going to get wonderful speed.

But shooting a little lower, I think its not that hard to come up with
a good compromise.

I'd imagine something like:

 - Primitives are glyphs and bezier shape objects
 - A set of standard shape objects like circle, rectangle,
   etc, derived from the base shape object.
 - Model is painting, not a canvas
 - Simple compositing modes (OVER, and maybe SATURATE for
   joining glyphs)

Could meet most needs pretty darn well. That is, something a lot like
Java2D, but maybe a bit simpler in some areas.

This primitive set, done with libart, would already have OK
performance for a lot of uses - and if you put XRENDER behind it, it
will blaze.

And its good enough for 98% of all printing applications. With a
little tweaking, you could probably make that 99.95%.

Regards,
                                        Owen

(Not a design proposal, just a quick sketch of some of my thoughts
in this area.)