X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Frenderable.h;h=9fe46956540d4af243e61b2a9316c7eb08ccf020;hb=0e8ffd3b59e9b5c52c66c22c9ae4f9d3544aa6bf;hp=8e31d5a7ac79e0f4a379b581da4b68ef37823c05;hpb=5172d32d67595ea0b70184fadcfcb8e023cccbc8;p=libs%2Fgl.git

diff --git a/source/renderable.h b/source/renderable.h
index 8e31d5a7..9fe46956 100644
--- a/source/renderable.h
+++ b/source/renderable.h
@@ -23,6 +23,9 @@ protected:
 public:
 	virtual ~Renderable() { }
 
+	/** Returns a key used for grouping Renderables in an InstanceScene. */
+	virtual long get_instance_key() const { return 0; }
+
 	virtual void render(const Tag & = Tag()) const;
 	virtual void render(Renderer &, const Tag & = Tag()) const;
 };