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, 11 insertions, 10 deletions

diff --git a/doc/lispref/display.texi b/doc/lispref/display.texi
index 95985ea5750..82af02fc384 100644
--- a/doc/lispref/display.texi
+++ b/doc/lispref/display.texi
@@ -5181,6 +5181,9 @@ values.  If both @code{:scale} and @code{:height}/@code{:width} are
 specified, the height/width will be adjusted by the specified scaling
 factor.
 
+@item :rotation @var{angle}
+Specifies a rotation angle in degrees.
+
 @item :index @var{frame}
 @xref{Multi-Frame Images}.
 
@@ -5323,14 +5326,15 @@ This function returns @code{t} if image @var{spec} has a mask bitmap.
 (@pxref{Input Focus}).
 @end defun
 
-@defun image-scaling-p &optional frame
-This function returns @code{t} if @var{frame} supports image scaling.
-@var{frame} @code{nil} or omitted means to use the selected frame
-(@pxref{Input Focus}).
+@defun image-transforms-p &optional frame
+This function returns @code{t} if @var{frame} supports image scaling
+and rotation.  @var{frame} @code{nil} or omitted means to use the
+selected frame (@pxref{Input Focus}).
 
-If image scaling is not supported, @code{:width}, @code{:height},
-@code{:scale}, @code{:max-width} and @code{:max-height} will only be
-usable through ImageMagick, if available (@pxref{ImageMagick Images}).
+If image transforms are not supported, @code{:rotation},
+@code{:width}, @code{:height}, @code{:scale}, @code{:max-width} and
+@code{:max-height} will only be usable through ImageMagick, if
+available (@pxref{ImageMagick Images}).
 @end defun
 
 @node XBM Images
@@ -5474,9 +5478,6 @@ The value, @var{type}, should be a symbol specifying the type of the
 image data, as found in @code{image-format-suffixes}.  This is used
 when the image does not have an associated file name, to provide a
 hint to ImageMagick to help it detect the image type.
-
-@item :rotation @var{angle}
-Specifies a rotation angle in degrees.
 @end table
 
 @node SVG Images