Support native image resizing on cairo

* src/xterm.c (x_cr_draw_image): Add arguments image_width and
image_height and support scaling.  All callers changed.
* src/image.c (Fimage_scaling_p): Return t when USE_CAIRO.
(x_set_image_size) [USE_CAIRO]: Record the scaled dimensions
in the image struct.
* src/dispextern.h (HAVE_NATIVE_SCALING): Define when
USE_CAIRO as well.

* etc/NEWS: Update the announcement of native image scaling.

1 files changed, 5 insertions, 2 deletions

diff --git a/src/image.c b/src/image.c
index 16c5978db6e..6e415ef1f70 100644
--- a/src/image.c
+++ b/src/image.c
@@ -1878,7 +1878,10 @@ x_set_image_size (struct frame *f, struct image *img)
   img->height = height;
 # endif
 
-# ifdef HAVE_XRENDER
+# ifdef USE_CAIRO
+  img->width = width;
+  img->height = height;
+# elif defined HAVE_XRENDER
   if (img->picture)
     {
       double xscale = img->width / (double) width;
@@ -9918,7 +9921,7 @@ DEFUN ("image-scaling-p", Fimage_scaling_p, Simage_scaling_p, 0, 1, 0,
 Return t if FRAME supports native scaling, nil otherwise.  */)
      (Lisp_Object frame)
 {
-#if defined (HAVE_NS) || defined (HAVE_NTGUI)
+#if defined (USE_CAIRO) || defined (HAVE_NS) || defined (HAVE_NTGUI)
   return Qt;
 #elif defined (HAVE_X_WINDOWS) && defined (HAVE_XRENDER)
   int event_basep, error_basep;