From 54c337e5d3860fa7333fae79a8d3fa39366c1873 Mon Sep 17 00:00:00 2001
From: Robby Findler <robby@racket-lang.org>
Date: Mon, 27 Dec 2010 21:48:27 -0600
Subject: [PATCH] 2htdp/image: use erase instead of clear to zero out a bitmap

---
 collects/2htdp/private/image-more.rkt |  4 ++--
 collects/mrlib/image-core.rkt         | 10 +++++-----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/collects/2htdp/private/image-more.rkt b/collects/2htdp/private/image-more.rkt
index 35437f9d15..7f22e575b5 100644
--- a/collects/2htdp/private/image-more.rkt
+++ b/collects/2htdp/private/image-more.rkt
@@ -71,7 +71,7 @@
                (inexact->exact (ceiling height)))]
          [bdc (make-object bitmap-dc% bm)])
     (send bdc set-smoothing 'aligned)
-    (send bdc clear)
+    (send bdc erase)
     (render-image image bdc 0 0)
     (send bdc set-bitmap #f)
     (send bm save-file filename 'png)))
@@ -1273,7 +1273,7 @@
          [bdc (make-object bitmap-dc% bm)]
          [c (make-object color%)]
          [bytes (make-bytes (* w h 4))])
-    (send bdc clear)
+    (send bdc erase)
     (render-image image bdc 0 0)
     (send bdc get-argb-pixels 0 0 w h bytes)
     (for/list ([i (in-range 0 (* w h 4) 4)])
diff --git a/collects/mrlib/image-core.rkt b/collects/mrlib/image-core.rkt
index 3b491eeb71..e9a4e19b4a 100644
--- a/collects/mrlib/image-core.rkt
+++ b/collects/mrlib/image-core.rkt
@@ -221,7 +221,7 @@ has been moved out).
               (add1 (inexact->exact (ceiling (bb-right bb)))) 
               (add1 (inexact->exact (ceiling (bb-bottom bb)))))]
          [bdc (new bitmap-dc% [bitmap bm])])
-    (send bdc clear)
+    (send bdc erase)
     (render-image img bdc 0 0)
     (begin0
         (send bdc get-bitmap)
@@ -261,7 +261,7 @@ has been moved out).
     
     (define/private (draw-into bm bdc bytes obj)
       (send bdc set-bitmap bm)
-      (send bdc clear)
+      (send bdc erase)
       (render-image obj bdc 0 0)
       (send bdc get-argb-pixels 0 0 (send bm get-width) (send bm get-height) bytes))
     
@@ -650,7 +650,7 @@ has been moved out).
                (+ 1 (ceiling (inexact->exact (bb-right bb))))
                (+ 1 (ceiling (inexact->exact (bb-bottom bb)))))]
          [bdc (make-object bitmap-dc% bm)])
-    (send bdc clear)
+    (send bdc erase)
     (render-image image bdc 0 0)
     (send bdc set-bitmap #f)
     (send bm save-file filename kind)))
@@ -989,13 +989,13 @@ the mask bitmap and the original bitmap are all together in a single bytes!
          
          (send bdc set-bitmap new-bm)
          (send bdc set-scale x-scale y-scale)
-         (send bdc clear)
+         (send bdc erase)
          (send bdc draw-bitmap orig-bm 0 0)
          
          (when new-mask
            (send bdc set-bitmap new-mask)
            (send bdc set-scale x-scale y-scale)
-           (send bdc clear)
+           (send bdc erase)
            (send bdc draw-bitmap orig-mask 0 0))
          
          (send bdc set-bitmap #f)