commit 13222e7ab16392c011bfacb86a375c458b8afe16
author Nigel Tao <nigeltao@golang.org> Fri May 27 14:03:57 2016 +1000
committer Nigel Tao <nigeltao@golang.org> Fri May 27 22:56:44 2016 +0000
tree 1749fca5a87cbba8945eba42dff42715a3231c35
parent b24f83b520c97b2c689ba2ebad4c04f537ab35dc

shiny/driver/x11driver: set the texture repeat to "pad".

This means that out-of-bound texture reads return the in-bound edge
values instead of returning zero. Since the picture filter is
"bilinear", this is noticeable when scaling the entirety of the texture
(when srcRect = tex.Bounds()), such as in the example/fluid program.
Before this commit, the edges in the destination window were feathered.
After this commit, they are crisp, the same as the gldriver.

See section 9 "Source and Mask Transformations" of
https://www.x.org/releases/current/doc/renderproto/renderproto.txt

Change-Id: I4e4827d35311790bac0cd092fecb3953707976cb
Reviewed-on: https://go-review.googlesource.com/23500
Reviewed-by: David Crawshaw <crawshaw@golang.org>