From Adrian Egli, "Improvements to the PSSM implementation"

include/osgShadow/ParallelSplitShadowMap

@@ -29,6 +29,7 @@
 #include <osg/Camera>
 #include <osg/Material>
 #include <osg/Depth>
+#include <osg/ClipPlane>
 
 #include <osgShadow/ShadowTechnique>
 
@@ -77,24 +78,45 @@ class OSGSHADOW_EXPORT ParallelSplitShadowMap :  public ShadowTechnique
         /** Set min near distance for splits */ 
         inline void setMinNearDistanceForSplits(double nd){ _split_min_near_dist=nd; }
 
-        /** use linear split (default: linear) */
-        inline void useLinearSplit(bool flag) { _linearSplit = flag;}
-
         /** set a user defined light for shadow simulation (sun light, ... ) 
          *    when this light get passed to pssm, the scene's light are no longer collected 
          *    and simulated. just this user passed light, it needs to be a directional light. 
          */
         inline void setUserLight(osg::Light* light) { _userLight = light; }
-             
-             
+                          
         /** Set the values for the ambient bias the shader will use.*/
         void setAmbientBias(const osg::Vec2& ambientBias );
-            
+
+        /**
+         * you can overwrite the fragment shader if you like to modify it yourself, own fragment shader can be used
+         */
+        class FragmentShaderGenerator : public osg::Referenced {
+            public:
+                /** 
+                 * generate the GLSL fragement shader 
+                 */
+                virtual std::string generateGLSL_FragmentShader_BaseTex(bool debug, unsigned int splitCount,double textureRes, bool filtered, unsigned int nbrSplits,unsigned int textureOffset);
+        };
+        
+        /** set fragment shader generator */
+        inline void setFragmentShaderGenerator(FragmentShaderGenerator* fsw) { _FragmentShaderGenerator = fsw;}
+        
+        /** enable / disable shadow filtering */
+        inline void enableShadowGLSLFiltering(bool filtering = true) {  _GLSL_shadow_filtered = filtering; }
+        
+        enum SplitCalcMode {
+            SPLIT_LINEAR,
+            SPLIT_EXP
+        };
+        
+        /** set split calculation mode */
+        inline void setSplitCalculationMode(SplitCalcMode scm=SPLIT_EXP) { _SplitCalcMode = scm; }
+        
+        
     protected :
 
         virtual ~ParallelSplitShadowMap() {}
 
-        std::string generateGLSL_FragmentShader_BaseTex(bool debug, unsigned int splitCount);
  
         struct PSSMShadowSplitTexture {
             // RTT
@@ -105,7 +127,7 @@ class OSGSHADOW_EXPORT ParallelSplitShadowMap :  public ShadowTechnique
             unsigned int                    _textureUnit;
 
 
-            osg::ref_ptr<osg::Depth>        _depth;
+            double                            _split_far;
 
             osg::ref_ptr<osg::Camera>       _debug_camera;
             osg::ref_ptr<osg::Texture2D>    _debug_texture;
@@ -127,8 +149,8 @@ class OSGSHADOW_EXPORT ParallelSplitShadowMap :  public ShadowTechnique
             unsigned int                      _resolution;
 
             osg::Uniform*                    _farDistanceSplit;
-
         };
+
         typedef std::map<unsigned int,PSSMShadowSplitTexture> PSSMShadowSplitTextureMap;
         PSSMShadowSplitTextureMap _PSSMShadowSplitTextureMap;
 
@@ -158,11 +180,12 @@ class OSGSHADOW_EXPORT ParallelSplitShadowMap :  public ShadowTechnique
         double _split_min_near_dist;
 
         double _move_vcam_behind_rcam_factor;
+ 
+        osg::ref_ptr<osg::Light> _userLight;
+        osg::ref_ptr<FragmentShaderGenerator> _FragmentShaderGenerator;
 
-        bool _linearSplit;
-
-        osg::Light* _userLight;
-        
+        bool _GLSL_shadow_filtered;
+        SplitCalcMode _SplitCalcMode;
         
         osg::Uniform*      _ambientBiasUniform;
         osg::Vec2d  _ambientBias;