From 9f72c9392ecdab081fdad9956534c0ef81d1b2d7 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Wed, 20 Jun 2007 12:00:29 +0000
Subject: [PATCH] Added code of support for contouring shaders

---
 include/osgTerrain/GeometryTechnique |  5 +++++
 src/osgTerrain/GeometryTechnique.cpp | 10 ++++++++++
 2 files changed, 15 insertions(+)

diff --git a/include/osgTerrain/GeometryTechnique b/include/osgTerrain/GeometryTechnique
index 7ed250e4a..343d10c96 100644
--- a/include/osgTerrain/GeometryTechnique
+++ b/include/osgTerrain/GeometryTechnique
@@ -109,6 +109,9 @@ class OSGTERRAIN_EXPORT GeometryTechnique : public TerrainTechnique
         
         
         
+        void setFilterBias(float filterBias);
+        float getFilterBias() const { return _filterBias; }
+        
         void setFilterWidth(float filterWidth);
         float getFilterWidth() const { return _filterWidth; }
 
@@ -136,6 +139,8 @@ class OSGTERRAIN_EXPORT GeometryTechnique : public TerrainTechnique
         osg::ref_ptr<TerrainGeometry>       _terrainGeometry;
         osg::ref_ptr<osg::Geometry>         _geometry;
         
+        float                               _filterBias;
+        osg::ref_ptr<osg::Uniform>          _filterBiasUniform;
         float                               _filterWidth;
         osg::ref_ptr<osg::Uniform>          _filterWidthUniform;
         osg::Matrix3                        _filterMatrix;
diff --git a/src/osgTerrain/GeometryTechnique.cpp b/src/osgTerrain/GeometryTechnique.cpp
index 8a5e97429..f83a8a4f7 100644
--- a/src/osgTerrain/GeometryTechnique.cpp
+++ b/src/osgTerrain/GeometryTechnique.cpp
@@ -29,6 +29,7 @@ using namespace osgTerrain;
 
 GeometryTechnique::GeometryTechnique()
 {
+    setFilterBias(0);
     setFilterWidth(0.1);
     setFilterMatrixAs(GAUSSIAN);
 }
@@ -42,6 +43,13 @@ GeometryTechnique::~GeometryTechnique()
 {
 }
 
+void GeometryTechnique::setFilterBias(float filterBias)
+{
+    _filterBias = filterBias;
+    if (!_filterBiasUniform) _filterBiasUniform = new osg::Uniform("filterBias",_filterBias);
+    else _filterBiasUniform->set(filterBias);
+}
+
 void GeometryTechnique::setFilterWidth(float filterWidth)
 {
     _filterWidth = filterWidth;
@@ -418,6 +426,7 @@ void GeometryTechnique::init()
             texture2D->setResizeNonPowerOfTwoHint(false);
             stateset->setTextureAttributeAndModes(color_index, texture2D, osg::StateAttribute::ON);
 
+            texture2D->setFilter(osg::Texture::MIN_FILTER, osg::Texture::LINEAR_MIPMAP_LINEAR);
             texture2D->setFilter(osg::Texture::MAG_FILTER, filter==TerrainNode::LINEAR ? osg::Texture::LINEAR :  osg::Texture::NEAREST);
             
             if (tf)
@@ -485,6 +494,7 @@ void GeometryTechnique::init()
 
             stateset->addUniform(_filterWidthUniform.get());
             stateset->addUniform(_filterMatrixUniform.get());
+            stateset->addUniform(_filterBiasUniform.get());
 
             osg::Uniform* lightingEnabled = new osg::Uniform("lightingEnabled",true);
             stateset->addUniform(lightingEnabled);