added missing file

git-svn-id: svn://svn.icculus.org/gtkradiant/GtkRadiant/trunk@96 8a3a26a2-13c4-0310-b231-cf6edde360e5

diff --git a/setup/data/tools/gl/utils.cg b/setup/data/tools/gl/utils.cg
new file mode 100644 (file)
index 0000000..63bfcb6
--- /dev/null
+++ b/setup/data/tools/gl/utils.cg
@@ -0,0 +1,36 @@
+/// ============================================================================
+/*
+Copyright (C) 2004 Robert Beckebans <trebor_7@users.sourceforge.net>
+Please see the file "AUTHORS" for a list of contributors
+
+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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+*/
+/// ============================================================================
+
+// fresnel approximation
+float  fast_fresnel(float3 I, float3 N, float3 fresnel_values)
+{
+       float power = fresnel_values.x;
+       float scale = fresnel_values.y;
+       float bias  = fresnel_values.z;
+
+       return bias + pow(1.0 - dot(I, N), power) * scale;
+}
+
+float3 CG_Expand(float3 v)
+{
+       return (v - 0.5) * 2;   // expand a range-compressed vector
+}