* lisp/image.el (image--compute-rotation): New function.
(image--compute-map, image--compute-original-map): Use it.
Ensure all transformations are applied or undone according to what
Emacs does internally. Call a transformation function only when
needed. Fix doc string.
(image--scale-map, image--rotate-map): Assume effective scale
argument.
(image--rotate-coord): Improve doc string.
(image--flip-map): Remove no more used argument FLIP.
* test/lisp/image-tests.el (image-create-image-with-map): Use a
valid SVG image otherwise `image-size' will not return a valid
value and calculation of scale could fail.
(image-transform-map): Update according to changed signature of
`image--flip-map'.
Now, when transforming an image, its :map is recomputed to fit.
Image map coordinates are integers, so when computing :map,
coordinates are rounded. To prevent an image from drifting from
its map after repeated transformations, 'create-image' now adds
a new image property :original-map, which is combined with the
image's transformation parameters to recompute :map.
* lisp/image.el (image-recompute-map-p): Add user option to
control whether :map is recomputed when an image is transformed.
(create-image): Create :map from :original-map and vice versa.
(image--delayed-change-size): Fix comment.
(image--change-size, image-rotate, image-flip-horizontally,
image-flip-vertically): Recompute image map after transformation
and mention 'image-recompute-map-p' in docstring.
(image--compute-map): Add function to compute a map from original
map.
(image--compute-original-map): Add function to compute an
original map from map.
(image--scale-map): Add function to scale a map based on :scale.
(image--rotate-map): Add function to rotate a map based on
:rotation.
(image--rotate-coord): Add function to rotate a map coordinate
pair.
(image--flip-map): Add function to flip a map based on :flip.
(image-increase-size, image-decrease-size, image-mouse-increase-size)
(image-mouse-decrease-size): Mention 'image-recompute-map-p' in
docstrings.
* etc/NEWS: Add NEWS entry.
* doc/lispref/display.texi (Image Descriptors): Document :original-map
and new user option 'image-recompute-map-p'.
* test/lisp/image-tests.el (image--compute-map-and-original-map):
Test 'image--compute-map' and 'image--compute-original-map'.
(image-tests--map-equal): Add equality predicate to compare image maps.
(image-create-image-with-map): Test that 'create-image' adds :map
and/or :original-map as appropriate.
(image-transform-map): Test functions related to transforming maps.
(Bug#69602)
* test/README: Mention $EMACS_TEST_DIRECTORY.
* test/lisp/image-tests.el (image-tests--emacs-images-directory):
Use `data-directory', for runs w/o of make.
(image-type/from-filename): Check for `image-load-path'.
* lisp/image.el (image-rotate): Extend with an optional argument
specifying the rotation in degrees (bug#35421).
* doc/lispref/display.texi (Showing Images):
* etc/NEWS: Document the change.
* test/lisp/image-tests.el (image-rotate): New test.
Problem reported privately by Michael Albinus.
* test/lisp/image-tests.el (image-type-from-file-header-test):
Don’t assume svg is a supported image type.
Prefer librsvg for display of splash.svg
When both librsvg and Imagemagick are available, Emacs should
prefer librsvg to render SVG images. However, Emacs was using
Imagemagick to render its own splash.svg file because
image-type-from-file-header returned nil for that file.
* lisp/image.el (image-type-from-buffer)
(image-type-from-file-header): Look at the first 8192 bytes of
the image, not just the first 256. For Emacs’s own splash.svg
file, image-type-header-regexps needs to look at 939 bytes.
8192 bytes is a reasonable number nowadays given typical file
system design.
* test/lisp/image-tests.el (image-tests--emacs-images-directory):
New contant.
(image-type-from-file-header-test): New test.
* lisp/image.el (image--set-property): Ensure new value is set even
in the unlikely case that the plist is empty. Fix off-by-one-link
error when deleting a property. (bug#35285)
* test/lisp/image-tests.el: New file.
(image--set-property): New test.
