X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=synfig-core%2Ftrunk%2Fsrc%2Fmodules%2Flyr_std%2Fwarp.cpp;h=60a41c7a36a9bf8a51b5f5778b574c180b90726e;hb=1c468ce8111bab2498742ea9959ffbcdaf74730f;hp=2110e0237b73a4274a81b1f53ac49bc3b638147f;hpb=e3dfe7e4df9f65f2331031103453d80c1268a8fd;p=synfig.git

diff --git a/synfig-core/trunk/src/modules/lyr_std/warp.cpp b/synfig-core/trunk/src/modules/lyr_std/warp.cpp
index 2110e02..60a41c7 100644
--- a/synfig-core/trunk/src/modules/lyr_std/warp.cpp
+++ b/synfig-core/trunk/src/modules/lyr_std/warp.cpp
@@ -6,6 +6,7 @@
 **
 **	\legal
 **	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
+**	Copyright (c) 2007 Chris Moore
 **
 **	This package is free software; you can redistribute it and/or
 **	modify it under the terms of the GNU General Public License as
@@ -516,7 +517,11 @@ Warp::accelerated_render(Context context,Surface *surface,int quality, const Ren
 		// Real trans_z[4];
 		Real z,minz(10000000000000.0f),maxz(0);
 
-
+		//! \todo checking the 4 corners for 0<=z<horizon*2 and using
+		//! only 4 corners which satisfy this condition isn't the
+		//! right thing to do.  It's possible that none of the 4
+		//! corners fall within that range, and yet content of the
+		//! tile does.
 		p=transform_forward(min);
 		z=transform_backward_z(p);
 		if(z>0 && z<horizon*2)
@@ -609,6 +614,16 @@ Warp::accelerated_render(Context context,Surface *surface,int quality, const Ren
 	Point min_point(bounding_rect.get_min());
 	Point max_point(bounding_rect.get_max());
 
+	// we're going to divide by the different of these pairs soon;
+	// if they're the same, we'll be dividing by zero, and we don't
+	// want to do that!
+	// \todo what should we do in this case?
+	if (min_point[0] == max_point[0] || min_point[1] == max_point[1])
+	{
+		surface->set_wh(renddesc.get_w(),renddesc.get_h());
+		surface->clear();
+		return true;
+	}
 
 	if(tl[0]>br[0])
 	{