[PATCH weston v2 15/16] pixman-renderer: implement source clipping

[Pekka Paalanen]

On Tue, 10 Mar 2015 12:39:58 -0700
Bill Spitzak <spitzak at gmail.com> wrote:

> Using the new pixman_image_t may be equivalent (I should check) but if 
> there is some speed problem it should be possible to get an arbitrary 
> subrectangle by making a new pixman_image_t directly from the buffer by 
> setting the stride to the full buffer stride and setting the origin and 
> the width and height to the subrectangle.

That is exactly what the patch does, doesn't it?
The patch is not copying any source pixels to the new pixman_image_t to
be sourced from.

- pq

> On 03/10/2015 06:01 AM, Pekka Paalanen wrote:
> 
> > This patch implements source clipping by taking each rectangle of the
> > source clip region, wrapping that sub-rect of the source image in a new
> > pixman_image_t, and compositing it separately. This might be very heavy as
> > we are painting the whole damage the number of rectangles times, but
> > practically always the number of rectangles is one.