Add racket-images-do-not-use-svg customization; closes #709

doc/generate.el

@@ -204,6 +204,7 @@
     racket-imagemagick-props
     racket-images-keep-last
     racket-images-system-viewer
+    racket-images-do-not-use-svg
     racket-pretty-print
     racket-repl-command-file
     "Other variables"

doc/racket-mode.texi

@@ -226,6 +226,7 @@ REPL variables
 * racket-imagemagick-props::
 * racket-images-keep-last::
 * racket-images-system-viewer::
+* racket-images-do-not-use-svg::
 * racket-pretty-print::
 * racket-repl-command-file::
 
@@ -3319,6 +3320,7 @@ Use some of the regexp search-based fontification from classic
 * racket-imagemagick-props::
 * racket-images-keep-last::
 * racket-images-system-viewer::
+* racket-images-do-not-use-svg::
 * racket-pretty-print::
 * racket-repl-command-file::
 @end menu
@@ -3413,6 +3415,15 @@ How many images to keep in the image cache.
 
 The image viewer program to use for @code{racket-view-image}.
 
+@node racket-images-do-not-use-svg
+@subsection racket-images-do-not-use-svg
+
+Do not use SVG to render images?
+
+Note: This value is used only when starting a back end -- @emph{not}
+for each run. If you change this, for it to take effect you must
+restart by using @code{racket-start-back-end}.
+
 @node racket-pretty-print
 @subsection racket-pretty-print
 

racket-cmd.el

@@ -94,7 +94,8 @@ Before doing anything runs the hook `racket-stop-back-end-hook'."
                           (if local-p
                               racket--rkt-source-dir
                             (racket--ensure-updated-back-end-on-remote))))
-           (svg-flag (if (and (boundp 'image-types)
+           (svg-flag (if (and (not racket-images-do-not-use-svg)
+                              (boundp 'image-types)
                               (fboundp 'image-type-available-p)
                               (or (and (memq 'svg image-types)
                                        (image-type-available-p 'svg))

racket-custom.el

@@ -338,6 +338,15 @@ pixels, supply (:max-width 500)."
   :type 'string
   :risky t)
 
+(defcustom racket-images-do-not-use-svg nil
+  "Do not use SVG to render images?
+
+Note: This value is used only when starting a back end -- /not/
+for each run. If you change this, for it to take effect you must
+restart by using `racket-start-back-end'."
+  :type 'boolean
+  :safe #'booleanp)
+
 (defcustom racket-pretty-print t
   "Use pretty-print instead of print in REPL?"
   :type 'boolean