X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=synfig-core%2Ftrunk%2Fsrc%2Fsynfig%2Fcolor.h;h=d54b0e942ed69966b7e92efbb5c4c423e7a1799d;hb=47a979c060132d120dbc8160aa9ae2e8c9d900c0;hp=7c8a356cabf1df6b43a0f5e7b1ac8c582c4c31c3;hpb=b177280b8815c394cb67c713eb34260ebb72de94;p=synfig.git

diff --git a/synfig-core/trunk/src/synfig/color.h b/synfig-core/trunk/src/synfig/color.h
index 7c8a356..d54b0e9 100644
--- a/synfig-core/trunk/src/synfig/color.h
+++ b/synfig-core/trunk/src/synfig/color.h
@@ -6,7 +6,7 @@
 **
 **	\legal
 **	Copyright (c) 2002-2005 Robert B. Quattlebaum Jr., Adrian Bentley
-**	Copyright (c) 2007 Chris Moore
+**	Copyright (c) 2007, 2008 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
@@ -524,6 +524,15 @@ public:
 			|| x==BLEND_HARD_LIGHT
 		;
 	}
+
+	//! a blending method is considered 'straight' if transparent pixels in the upper layer can affect the result of the blend
+	static bool is_straight(BlendMethod x)
+	{
+		return x==BLEND_STRAIGHT
+			|| x==BLEND_STRAIGHT_ONTO
+			|| x==BLEND_ALPHA_BRIGHTEN
+		;
+	}
 /*protected:
 
 	value_type& operator[](const int i)