Add native image rotation and cropping

* lisp/image.el (image--get-imagemagick-and-warn): Only fallback to
ImageMagick if native transforms aren't available.
* src/dispextern.h (INIT_MATRIX, COPY_MATRIX, MULT_MATRICES): New
macros for matrix manipulation.
(HAVE_NATIVE_SCALING, HAVE_NATIVE_TRANSFORMS): Rename and change all
relevant locations.
* src/image.c (x_set_image_rotation):
(x_set_transform): New functions.
(x_set_image_size): Use transform matrix for resizing under X and NS.
(x_set_image_crop): New function.
(lookup_image): Use the new transform functions.
(Fimage_scaling_p, Fimage_transforms_p): Rename and update all
callers.
* src/nsimage.m (ns_load_image): Remove rotation code.
(ns_image_set_transform): New function.
([EmacsImage dealloc]): Release the saved transform.
([EmacsImage rotate:]): Remove unneeded method.
([EmacsImage setTransform:]): New method.
* src/nsterm.h (EmacsImage): Add transform property and update method
definitions.
* src/nsterm.m (ns_dumpglyphs_image): Use the transform to draw the
image correctly.
* src/xterm.c (x_composite_image): Use PictOpSrc as we don't care
about alpha values here.
* doc/lispref/display.texi (Image Descriptors): Add :rotation.
(ImageMagick Images): Remove :rotation.

1 files changed, 1 insertions, 4 deletions

diff --git a/src/xterm.c b/src/xterm.c
index ccc84dcc716..c064647da0c 100644
--- a/src/xterm.c
+++ b/src/xterm.c
@@ -2883,10 +2883,7 @@ x_composite_image (struct glyph_string *s, Pixmap dest,
       destination = XRenderCreatePicture (display, dest,
                                           default_format, 0, &attr);
 
-      /* FIXME: It may make sense to use PictOpSrc instead of
-         PictOpOver, as I don't know if we care about alpha values too
-         much here.  */
-      XRenderComposite (display, PictOpOver,
+      XRenderComposite (display, PictOpSrc,
                         s->img->picture, s->img->mask_picture, destination,
                         srcX, srcY,
                         srcX, srcY,