win32: gl bitmaps

original commit: b98ba3e60b5173dec8f6ca6970592c8ab2441046

collects/mred/private/wx/win32/dc.rkt

@@ -21,7 +21,7 @@
 
 (define win32-bitmap%
   (class bitmap%
-    (init w h hwnd)
+    (init w h hwnd [gl-config #f])
     (super-make-object (make-alternate-bitmap-kind w h))
 
     (define s
@@ -41,6 +41,14 @@
           (cairo_destroy cr))
         s))
     
+    (define gl (and gl-config
+                    (let ([hdc (cairo_win32_surface_get_dc s)])
+                      (set-cpointer-tag! hdc 'HDC)
+                      (create-gl-context hdc 
+                                         gl-config
+                                         #t))))
+    (define/override (get-bitmap-gl-context) gl)
+
     (define/override (ok?) #t)
     (define/override (is-color?) #t)
     (define/override (has-alpha-channel?) #f)

collects/mred/private/wx/win32/procs.rkt

@@ -106,6 +106,6 @@
 (define/top (make-gl-bitmap [exact-positive-integer? w]
                             [exact-positive-integer? h]
                             [gl-config% c])
-  (make-object win32-bitmap% w h #f))
+  (make-object win32-bitmap% w h #f c))
 
 (define (check-for-break) #f)