color.el (color-name-to-rgb): Use the white color to find the max color component value and return correctly computed values.

 (color-name-to-rgb): Add missing float conversion for max value.

2 files changed, 10 insertions, 1 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 8fa8031d125..ab813e21922 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,9 @@
+2012-01-19  Julien Danjou  <julien@danjou.info>
+
+        * color.el (color-name-to-rgb): Use the white color to find the max
+        color component value and return correctly computed values.
+        (color-name-to-rgb): Add missing float conversion for max value.
+
 2012-01-19  Martin Rudalics  <rudalics@gmx.at>
 
         * window.el (window--state-get-1, window-state-get): Do not use
diff --git a/lisp/color.el b/lisp/color.el
index ff7f0eee4e6..6fab613ba69 100644
--- a/lisp/color.el
+++ b/lisp/color.el
@@ -53,7 +53,10 @@ numbers, (RED GREEN BLUE), each between 0.0 and 1.0 inclusive.
 Optional arg FRAME specifies the frame where the color is to be
 displayed.  If FRAME is omitted or nil, use the selected frame.
 If FRAME cannot display COLOR, return nil."
-  (mapcar (lambda (x) (/ x 65535.0)) (color-values color frame)))
+  ;; `colors-values' maximum value is either 65535 or 65280 depending on the
+  ;; display system. So we use a white conversion to get the max value.
+  (let ((valmax (float (car (color-values "#ffffff")))))
+    (mapcar (lambda (x) (/ x valmax)) (color-values color frame))))
 
 (defun color-rgb-to-hex  (red green blue)
   "Return hexadecimal notation for the color RED GREEN BLUE.