Cocoa: avoid backing-dc failure on zero-sized canvas

Closes https://github.com/racket/racket#1255
2016-02-22 05:04:37 -07:00 · 2016-02-22 05:04:37 -07:00 · be30bf721d
commit be30bf721d
parent c8c8ce64eb
1 changed files with 5 additions and 3 deletions
--- a/gui-lib/mred/private/wx/cocoa/dc.rkt
+++ b/gui-lib/mred/private/wx/cocoa/dc.rkt
@ -153,9 +153,11 @@
               (display-bitmap-resolution 0 void)))

 (define (make-window-bitmap w h win [trans? #t] [flipped? #f])
-  (if win
-      (make-object layer-bitmap% w h win trans? flipped?)
-      (make-screen-bitmap w h)))
+  (let ([w (max 1 w)]
+        [h (max 1 h)])
+    (if win
+        (make-object layer-bitmap% w h win trans? flipped?)
+        (make-screen-bitmap w h))))

 (define layer-bitmap%
  (class quartz-bitmap%