use pen's alpha color stuff in 2htdp/image

original commit: 830c797ee44e77f8a53477240979add83edebc17
2010-12-31 10:25:01 -06:00 · 2010-12-31 10:25:01 -06:00 · 92e830508d
commit 92e830508d
parent c4dd75a553
1 changed files with 2 additions and 1 deletions
--- a/collects/mrlib/image-core.rkt
+++ b/collects/mrlib/image-core.rkt
@ -1065,7 +1065,8 @@ the mask bitmap and the original bitmap are all together in a single bytes!
      (make-object color% 
        (color-red color)
        (color-green color)
-        (color-blue color))))
+        (color-blue color)
+        (/ (color-alpha color) 255))))


 (define (pen->pen-obj/cache pen)