Introduced new osg::PatchParameter StateAttribute class to wrap up glPatchParameter associated state.

Note, osg::Program::setParameter(GL_PATCH_VERTICES,num); is nolonger support and should be replaced by using the new PatchParameter class.

examples/osgtessellationshaders/osgtessellationshaders.cpp

@@ -4,6 +4,7 @@
  */
 
 #include <osg/Program>
+#include <osg/PatchParameter>
 #include <osg/ShapeDrawable>
 #include <osgViewer/Viewer>
 #include <osgViewer/ViewerEventHandlers>
@@ -175,7 +176,6 @@ osg::ref_ptr<osg::Program> createProgram(){
     program->setParameter(GL_GEOMETRY_VERTICES_OUT_EXT, 3);
     program->setParameter(GL_GEOMETRY_INPUT_TYPE_EXT, GL_TRIANGLES);
     program->setParameter(GL_GEOMETRY_OUTPUT_TYPE_EXT, GL_TRIANGLE_STRIP);
-    program->setParameter(GL_PATCH_VERTICES,3);
     return program;
 }
 
@@ -213,6 +213,7 @@ public:
         return osgGA::GUIEventHandler::handle(ea,gaa);
     }
 };
+
 int main(int argc, char* argv[])
 {
     osgViewer::Viewer viewer;
@@ -226,6 +227,7 @@ int main(int argc, char* argv[])
     state->addUniform(new osg::Uniform("LightPosition",osg::Vec3(0.25f, 0.25f, 1.0f)));
     state->addUniform(tessInnerU.get());
     state->addUniform(tessOuterU.get());
+    state->setAttribute(new osg::PatchParameter(3));
     state->setAttribute(program.get());
     
     // switch on the uniforms that track the modelview and projection matrices

include/osg/PatchParameter

@@ -0,0 +1,88 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
+ *
+ * This library is open source and may be redistributed and/or modified under
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ *
+ * This library 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
+ * OpenSceneGraph Public License for more details.
+*/
+
+#ifndef OSG_PATCHPARAMETER
+#define OSG_PATCHPARAMETER 1
+
+#include <osg/Vec2>
+#include <osg/Vec4>
+#include <osg/StateAttribute>
+#include <osg/GL2Extensions>
+
+namespace osg {
+
+/** Class which encapsulates glPatchParameter(..).
+*/
+class OSG_EXPORT PatchParameter : public StateAttribute
+{
+    public :
+
+        PatchParameter(GLint vertices=3);
+
+        /** Copy constructor using CopyOp to manage deep vs shallow copy.*/
+        PatchParameter(const PatchParameter& rhs,const CopyOp& copyop=CopyOp::SHALLOW_COPY):
+            StateAttribute(rhs,copyop),
+            _vertices(rhs._vertices),
+            _patchDefaultInnerLevel(rhs._patchDefaultInnerLevel),
+            _patchDefaultOuterLevel(rhs._patchDefaultOuterLevel) {}
+
+
+        META_StateAttribute(osg, PatchParameter, PATCH_PARAMETER);
+
+        /** return -1 if *this < *rhs, 0 if *this==*rhs, 1 if *this>*rhs.*/
+        virtual int compare(const StateAttribute& sa) const
+        {
+            // check the types are equal and then create the rhs variable
+            // used by the COMPARE_StateAttribute_Parameter macros below.
+            COMPARE_StateAttribute_Types(PatchParameter,sa)
+
+            // compare each parameter in turn against the rhs.
+            COMPARE_StateAttribute_Parameter(_vertices)
+            COMPARE_StateAttribute_Parameter(_patchDefaultInnerLevel)
+            COMPARE_StateAttribute_Parameter(_patchDefaultOuterLevel)
+
+            return 0; // passed all the above comparison macros, must be equal.
+        }
+
+        /** Set GL_PATCH_VERTICES parameter.*/
+        void setVertices(GLint vertices) { _vertices = vertices; }
+
+        /** Get GL_PATCH_VERTICES parameter.*/
+        GLint getVertices() const { return _vertices; }
+        
+        /** Set GL_PATCH_DEFAULT_INNER_LEVEL parameter.*/
+        void setPatchDefaultInnerLevel(const osg::Vec2& level) { _patchDefaultInnerLevel = level; }
+
+        /** Get GL_PATCH_DEFAULT_INNER_LEVEL parameter.*/
+        const osg::Vec2& getPatchDefaultInnerLevel() const { return _patchDefaultInnerLevel; }
+        
+        /** Set GL_PATCH_DEFAULT_OUTER_LEVEL parameter.*/
+        void setPatchDefaultOuterLevel(const osg::Vec4& level) { _patchDefaultOuterLevel = level; }
+
+        /** Get GL_PATCH_DEFAULT_INNER_LEVEL parameter.*/
+        const osg::Vec4& getPatchDefaultOuterLevel() const { return _patchDefaultOuterLevel; }
+
+        virtual void apply(State& state) const;
+
+    protected:
+
+        virtual ~PatchParameter();
+
+        GLint           _vertices;
+        osg::Vec2       _patchDefaultInnerLevel;
+        osg::Vec4       _patchDefaultOuterLevel;
+};
+
+}
+
+#endif

include/osg/Program

@@ -99,9 +99,6 @@ class OSG_EXPORT Program : public osg::StateAttribute
         void setParameter( GLenum pname, GLint value );
         GLint getParameter( GLenum pname ) const;
 
-        void setParameterfv( GLenum pname, const GLfloat* value );
-        const GLfloat* getParameterfv( GLenum pname ) const;
-        
         /** Set/get compute shader work groups */
         void setComputeGroups( GLint numGroupsX, GLint numGroupsY, GLint numGroupsZ );
         void getComputeGroups( GLint& numGroupsX, GLint& numGroupsY, GLint& numGroupsZ ) const;
@@ -385,13 +382,6 @@ class OSG_EXPORT Program : public osg::StateAttribute
         GLint _geometryInputType;
         GLint _geometryOutputType;
 
-        /** Parameter maintained with glPatchParameteri */
-        GLint _patchVertices;
-
-        /** Parameter maintained with glPatchParameterfv */
-        // todo add tessellation default level
-        //GLfloat _patchDefaultInnerLevel[2];
-        //GLfloat _patchDefaultOuterLevel[4];
         
         /** Parameter maintained with glDispatchCompute */
         GLint _numGroupsX;

include/osg/StateAttribute

@@ -190,7 +190,9 @@ class OSG_EXPORT StateAttribute : public Object
             UNIFORMBUFFERBINDING,
             TRANSFORMFEEDBACKBUFFERBINDING,
 
-            ATOMICCOUNTERBUFFERBINDING
+            ATOMICCOUNTERBUFFERBINDING,
+            
+            PATCH_PARAMETER
         };
 
         /** Simple pairing between an attribute type and the member within that attribute type group.*/

src/osg/CMakeLists.txt

@@ -117,6 +117,7 @@ SET(TARGET_H
     ${HEADER_PATH}/OccluderNode
     ${HEADER_PATH}/OcclusionQueryNode
     ${HEADER_PATH}/OperationThread
+    ${HEADER_PATH}/PatchParameter
     ${HEADER_PATH}/PagedLOD
     ${HEADER_PATH}/Plane
     ${HEADER_PATH}/Point
@@ -301,6 +302,7 @@ SET(TARGET_SRC
     OccluderNode.cpp
     OcclusionQueryNode.cpp
     OperationThread.cpp
+    PatchParameter.cpp
     PagedLOD.cpp
     Point.cpp
     PointSprite.cpp

src/osg/PatchParameter.cpp

@@ -0,0 +1,42 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2006 Robert Osfield
+ *
+ * This library is open source and may be redistributed and/or modified under
+ * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or
+ * (at your option) any later version.  The full license is in LICENSE file
+ * included with this distribution, and on the openscenegraph.org website.
+ *
+ * This library 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
+ * OpenSceneGraph Public License for more details.
+*/
+#include <osg/PatchParameter>
+#include <osg/State>
+#include <osg/Notify>
+#include <osg/io_utils>
+
+using namespace osg;
+
+PatchParameter::PatchParameter(GLint vertices):
+    _vertices(vertices),
+    _patchDefaultInnerLevel(1.0f,1.0f),
+    _patchDefaultOuterLevel(1.0f,1.0f,1.0f,1.0f)
+{
+}
+
+
+PatchParameter::~PatchParameter()
+{
+}
+
+void PatchParameter::apply(State& state) const
+{
+    GL2Extensions* extensions = GL2Extensions::Get( state.getContextID(), true );
+    if (extensions->areTessellationShadersSupported() )
+    {
+        
+        extensions->glPatchParameteri( GL_PATCH_VERTICES, _vertices );
+        extensions->glPatchParameterfv( GL_PATCH_DEFAULT_INNER_LEVEL, _patchDefaultInnerLevel.ptr() );
+        extensions->glPatchParameterfv( GL_PATCH_DEFAULT_OUTER_LEVEL, _patchDefaultOuterLevel.ptr() );
+    }
+}

src/osg/Program.cpp

@@ -137,7 +137,6 @@ void Program::ProgramBinary::assign(unsigned int size, const unsigned char* data
 Program::Program() :
     _geometryVerticesOut(1), _geometryInputType(GL_TRIANGLES),
     _geometryOutputType(GL_TRIANGLE_STRIP),
-    _patchVertices(3),
     _numGroupsX(0), _numGroupsY(0), _numGroupsZ(0)
 {
 }
@@ -167,8 +166,6 @@ Program::Program(const Program& rhs, const osg::CopyOp& copyop):
     _geometryInputType = rhs._geometryInputType;
     _geometryOutputType = rhs._geometryOutputType;
 
-    _patchVertices = rhs._patchVertices;
-    
     _numGroupsX = rhs._numGroupsX;
     _numGroupsY = rhs._numGroupsY;
     _numGroupsZ = rhs._numGroupsZ;
@@ -206,9 +203,6 @@ int Program::compare(const osg::StateAttribute& sa) const
     if( _geometryOutputType < rhs._geometryOutputType ) return -1;
     if( rhs._geometryOutputType < _geometryOutputType ) return 1;
 
-    if( _patchVertices < rhs._patchVertices ) return -1;
-    if( rhs._patchVertices < _patchVertices ) return 1;
-    
     if( _numGroupsX < rhs._numGroupsX ) return -1;
     if( rhs._numGroupsX < _numGroupsX ) return 1;
     
@@ -360,44 +354,14 @@ void Program::setParameter( GLenum pname, GLint value )
             //dirtyProgram();    // needed?
             break;
         case GL_PATCH_VERTICES:
-            _patchVertices = value;
-            dirtyProgram();
+            OSG_WARN << "Program::setParameter invalid param " << GL_PATCH_VERTICES << ", use osg::PatchParameter when setting GL_PATCH_VERTICES."<<std::endl;
             break;
         default:
-            OSG_WARN << "setParameter invalid param " << pname << std::endl;
+            OSG_WARN << "Program::setParameter invalid param " << pname << std::endl;
             break;
     }
 }
 
-void Program::setParameterfv( GLenum pname, const GLfloat* /*value*/ )
-{
-    switch( pname )
-    {
-      // todo tessellation default level
-        case GL_PATCH_DEFAULT_INNER_LEVEL:
-            break;
-        case GL_PATCH_DEFAULT_OUTER_LEVEL:
-            break;
-        default:
-            OSG_WARN << "setParameter invalid param " << pname << std::endl;
-            break;
-    }
-}
-
-const GLfloat* Program::getParameterfv( GLenum pname ) const
-{
-    /*switch( pname )
-    {
-      ;
-      // todo tessellation default level
-      //        case GL_PATCH_DEFAULT_INNER_LEVEL: return _patchDefaultInnerLevel;
-      //        case GL_PATCH_DEFAULT_OUTER_LEVEL: return _patchDefaultOuterLevel;
-
-    }*/
-    OSG_WARN << "getParameter invalid param " << pname << std::endl;
-    return 0;
-}
-
 GLint Program::getParameter( GLenum pname ) const
 {
     switch( pname )
@@ -405,7 +369,6 @@ GLint Program::getParameter( GLenum pname ) const
         case GL_GEOMETRY_VERTICES_OUT_EXT: return _geometryVerticesOut;
         case GL_GEOMETRY_INPUT_TYPE_EXT:   return _geometryInputType;
         case GL_GEOMETRY_OUTPUT_TYPE_EXT:  return _geometryOutputType;
-        case GL_PATCH_VERTICES:            return _patchVertices;
     }
     OSG_WARN << "getParameter invalid param " << pname << std::endl;
     return 0;
@@ -604,13 +567,7 @@ void Program::PerContextProgram::linkProgram(osg::State& state)
             _extensions->glProgramParameteri( _glProgramHandle, GL_GEOMETRY_INPUT_TYPE_EXT, _program->_geometryInputType );
             _extensions->glProgramParameteri( _glProgramHandle, GL_GEOMETRY_OUTPUT_TYPE_EXT, _program->_geometryOutputType );
         }
-
-        if (_extensions->areTessellationShadersSupported() )
-        {
-            _extensions->glPatchParameteri( GL_PATCH_VERTICES, _program->_patchVertices );
-            // todo: add default tessellation level
-        }
-
+        
         // Detach removed shaders
         for( unsigned int i=0; i < _shadersToDetach.size(); ++i )
         {

src/osgWrappers/serializers/osg/PatchParameter.cpp

@@ -0,0 +1,14 @@
+#include <osg/PatchParameter>
+#include <osgDB/ObjectWrapper>
+#include <osgDB/InputStream>
+#include <osgDB/OutputStream>
+
+REGISTER_OBJECT_WRAPPER( PatchParameter,
+                         new osg::PatchParameter,
+                         osg::PatchParameter,
+                         "osg::Object osg::StateAttribute osg::PatchParameter" )
+{
+    ADD_INT_SERIALIZER( Vertices, 3);
+    ADD_VEC2_SERIALIZER( PatchDefaultInnerLevel, osg::Vec2(1.0f,1.0f));
+    ADD_VEC4_SERIALIZER( PatchDefaultOuterLevel, osg::Vec4(1.0f,1.0f,1.0f,1.0f));
+}