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

[Bill Spitzak]

On 03/11/2015 03:13 AM, Pekka Paalanen wrote:
> 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.

Yes you are right, I should have looked at the patch.

I thought you were calling a pixman function to create the subimage from 
the main image, and was not certain if it did this. But your code is 
calling pixman_image_create_bits_no_clear with pointers to the buffer.