gtk: initialize canvas backing to white

original commit: 23908c23728d16cb3b7e1799180f4d6e5e5965c5
2010-11-07 07:16:12 -07:00 · 2010-11-07 07:16:12 -07:00 · a23671380f
commit a23671380f
parent 0700c8c5dd
1 changed files with 6 additions and 0 deletions
--- a/collects/mred/private/wx/gtk/dc.rkt
+++ b/collects/mred/private/wx/gtk/dc.rkt
@ -38,6 +38,12 @@
                                 w
                                 h))

+    ;; initialize bitmap to white:
+    (let ([cr (cairo_create s)])
+      (cairo_set_source_rgba cr 1.0 1.0 1.0 1.0)
+      (cairo_paint cr)
+      (cairo_destroy cr))
+
    ;; `get-gdk-pixmap' and `install-gl-context' are
    ;; localized in "gl-context.rkt"
    (define/public (get-gdk-pixmap) pixmap)