From Mike Weiblen's osgGL2 node kit which support the latest OpenGL 2.0 extensions.

examples/osgshaders/GL2Scene.cpp

@@ -0,0 +1,174 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield 
+ * Copyright (C) 2003 3Dlabs Inc. Ltd.
+ *
+ * This application is open source and may be redistributed and/or modified   
+ * freely and without restriction, both in commericial and non commericial applications,
+ * as long as this copyright notice is maintained.
+ * 
+ * This application 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.
+*/
+
+/* file:	examples/osgshaders/GL2Scene.cpp
+ * author:	Mike Weiblen 2003-07-14
+ *
+ * Compose a scene of several instances of a model, with a different
+ * OpenGL Shading Language shader applied to each.
+ *
+ * See http://www.3dlabs.com/opengl2/ for more information regarding
+ * the OpenGL Shading Language.
+*/
+
+#include <osg/ShapeDrawable>
+#include <osg/PositionAttitudeTransform>
+#include <osg/Geode>
+#include <osg/Notify>
+#include <osgDB/ReadFile>
+#include <osgDB/FileUtils>
+#include <osgUtil/Optimizer>
+#include <osgGL2/ProgramObject>
+
+
+///////////////////////////////////////////////////////////////////////////
+// OpenGL Shading Language source code for the "microshader" example.
+
+static const char *microshaderVertSource = {
+    "varying vec3 color;"
+    "void main(void)"
+    "{"
+	"gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;"
+	"color = gl_Vertex.zyx * 1.0;"
+    "}"
+};
+
+static const char *microshaderFragSource = {
+    "varying vec3 color;"
+    "void main(void)"
+    "{"
+	"gl_FragColor = vec4(color, 1.0);"
+    "}"
+};
+
+///////////////////////////////////////////////////////////////////////////
+
+static osg::Group* rootNode;
+static osg::Node* masterModel;
+
+// Add a reference to the masterModel at the specified translation, and
+// return its StateSet so we can easily attach StateAttributes.
+static osg::StateSet*
+CloneMaster(float x, float y, float z )
+{
+    osg::PositionAttitudeTransform* xform = new osg::PositionAttitudeTransform();
+    xform->setPosition(osg::Vec3(x, y, z));
+    xform->addChild(masterModel);
+    rootNode->addChild(xform);
+    return xform->getOrCreateStateSet();
+}
+
+// Create some geometry upon which to render GL2 shaders.
+static osg::Geode*
+CreateModel()
+{
+    osg::Geode* geode = new osg::Geode();
+    geode->addDrawable(new osg::ShapeDrawable(new osg::Sphere(osg::Vec3(0.0f,0.0f,0.0f),1.0f)));
+    geode->addDrawable(new osg::ShapeDrawable(new osg::Cone(osg::Vec3(2.2f,0.0f,-0.4f),0.9f,1.8f)));
+    geode->addDrawable(new osg::ShapeDrawable(new osg::Cylinder(osg::Vec3(4.4f,0.0f,0.0f),1.0f,1.4f)));
+    return geode;
+}
+
+// read vert & frag shader source code from a pair of files.
+static void
+LoadShaderSource( osgGL2::ProgramObject* progObj, std::string baseFileName )
+{
+    std::string vertFileName = osgDB::findDataFile(baseFileName + ".vert");
+    if( vertFileName.length() != 0 )
+    {
+	osgGL2::ShaderObject* vertObj = new osgGL2::ShaderObject( osgGL2::ShaderObject::VERTEX );
+	vertObj->loadShaderSourceFromFile( vertFileName.c_str() );
+	progObj->addShader( vertObj );
+    }
+    else
+    {
+	osg::notify(osg::WARN) << "Warning: file \"" << baseFileName+".vert" << "\" not found." << std::endl;
+    }
+
+    std::string fragFileName = osgDB::findDataFile(baseFileName + ".frag");
+    if( fragFileName.length() != 0 )
+    {
+	osgGL2::ShaderObject* fragObj = new osgGL2::ShaderObject( osgGL2::ShaderObject::FRAGMENT );
+	fragObj->loadShaderSourceFromFile( fragFileName.c_str() );
+	progObj->addShader( fragObj );
+    }
+    else
+    {
+	osg::notify(osg::WARN) << "Warning: file \"" << baseFileName+".frag" << "\" not found." << std::endl;
+    }
+}
+
+///////////////////////////////////////////////////////////////////////////
+// Compose a scenegraph with examples of GL2 shaders
+
+#define ZGRID 2.2
+
+osg::Node*
+GL2Scene()
+{
+    osg::StateSet* ss;
+    osgGL2::ProgramObject* progObj;
+
+    // the rootNode of our created graph.
+    rootNode = new osg::Group;
+    ss = rootNode->getOrCreateStateSet();
+
+    // attach an "empty" ProgramObject to the rootNode as a default
+    // StateAttribute.  An empty ProgramObject (ie without any attached
+    // ShaderObjects) is a special case, which means to use the
+    // OpenGL 1.x "fixed functionality" rendering pipeline.
+    progObj = new osgGL2::ProgramObject;
+    ss->setAttributeAndModes(progObj, osg::StateAttribute::ON);
+
+    // put the unadorned masterModel at the origin for comparison.
+    masterModel = CreateModel();
+    rootNode->addChild(masterModel);
+
+    // add logo overlays
+    //rootNode->addChild( osgDB::readNodeFile( "3dl_ogl.logo" ) );
+
+    //
+    // create references to the masterModel and attach shaders
+    //
+
+    // apply the simple microshader example
+    // (the shader sources are hardcoded above in this .cpp file)
+    ss = CloneMaster(0,0,ZGRID*1);
+    progObj = new osgGL2::ProgramObject;
+    progObj->addShader( new osgGL2::ShaderObject( osgGL2::ShaderObject::VERTEX, microshaderVertSource ) );
+    progObj->addShader( new osgGL2::ShaderObject( osgGL2::ShaderObject::FRAGMENT, microshaderFragSource ) );
+    ss->setAttributeAndModes(progObj, osg::StateAttribute::ON);
+
+    // load the "specular brick" shader from a pair of source files.
+    ss = CloneMaster(0,0,ZGRID*2);
+    progObj = new osgGL2::ProgramObject;
+    LoadShaderSource( progObj, "shaders/brick" );
+    ss->setAttributeAndModes(progObj, osg::StateAttribute::ON);
+
+    // load the "gold screen" shader from a pair of source files.
+    ss = CloneMaster(0,0,ZGRID*3);
+    progObj = new osgGL2::ProgramObject;
+    LoadShaderSource( progObj, "shaders/screen" );
+    ss->setAttributeAndModes(progObj, osg::StateAttribute::ON);
+
+    return rootNode;
+}
+
+
+void
+GL2Update()
+{
+    /* TODO : update uniform values for shader animation */
+}
+
+/*EOF*/
+