[Cairo] Clip rectangle

[Carl Worth]

On Jul 29, 2003, Soorya Kuloor wrote:
 > Here are 2 patches that implement cairo_surfcae_set_clip_rectangle(). I
 > could not find a way to implement cairo_surface_clip_restore(). Any help
 > in implementing this is appreciated.

Soorya,

Thanks for doing this work and contributing it.

I know that these patches implement an API that I proposed, but I've
now decided against this interface for a couple of reasons:

1) I want to move rendering state information away from the surface
   objects into the single graphics state within cairo_t.

2) We shouldn't implement a new clipping interface with different
   semantics, if we can use the existing clipping interface for both
   purposes.

Point 2 wasn't obvious at the time this patch was put together. But I
think the subsequent work by Graydon Hoare makes a good case that we
should be able to use cairo_rectangle/cairo_clip to implement
efficient clipping for pixel-aligned rectangles.

-Carl

PS. Yes, I am awakening an ancient thread here. I'm currently going
through old cairo posts that had never been been properly responded
to. I want to make sure nothing useful gets dropped on the floor.