Cycles OSL: refactoring and fixes

* Moved kernel/osl/nodes to kernel/shaders
* Renamed standard attributes to use geom:, particle:, object: prefixes
* Update stdosl.h to properly reflect the closures we support
* Fix the wrong stdosl.h being used for building shaders
* Add geom:numpolyvertices, geom:trianglevertices, geom:polyvertices attributes

intern/cycles/kernel/shaders/node_light_falloff.osl

@@ -0,0 +1,46 @@
+/*
+ * Copyright 2012, Blender Foundation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "stdosl.h"
+
+shader node_light_falloff(
+	float Strength = 0.0,
+	float Smooth = 0.0,
+	output float Quadratic = 0.0,
+	output float Linear = 0.0,
+	output float Constant = 0.0)
+{
+	float ray_length = 0.0;
+	float strength = Strength;
+	getattribute("path:ray_length", ray_length);
+
+	if (Smooth > 0.0) {
+		float squared = ray_length*ray_length;
+		strength *= squared / (Smooth + squared);
+	}
+
+	/* Quadratic */ 
+	Quadratic = strength;
+	
+	/* Linear */
+	Linear = (strength*ray_length);
+
+	/* Constant */
+	Constant = (strength*ray_length*ray_length);
+}
+