$NetBSD: patch-aq,v 1.2 2006/02/27 15:49:56 joerg Exp $

--- color-dither.cc.orig	1995-11-14 05:46:09.000000000 +0000
+++ color-dither.cc
@@ -169,15 +169,19 @@ class DitherWindowRenderer : public Pseu
 public:
 	DitherWindowRenderer(VideoWindow* vw, int decimation,
 			     DitherColorModel& cm) :
+		method_(NULL),
 		PseudoWindowRenderer(vw, decimation, cm.graylut()),
 		cm_(cm) { }
 	void render(const u_char* frm, int off, int x, int w, int h) {
-		(this->*method_)(frm, off, x, w, h);
+		if (this->method_)
+			(this->*method_)(frm, off, x, w, h);
+		else
+			dither_null(frm, off, x, w, h);
 	}
 protected:
 	DitherColorModel& cm_;
 	virtual void update();
-	virtual void disable() { method_ = PseudoWindowRenderer::dither_null; }
+	virtual void disable() { method_ = NULL; }
 	DitherMethod method_;
 	void dither_422(const u_char* frm, u_int off, u_int x,
 			u_int width, u_int height) const;