From Ruben, addition of osg::PointSprite and osgpointsprite example.

src/osg/PointSprite.cpp

@@ -0,0 +1,36 @@
+/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 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/GLExtensions>
+#include <osg/GL>
+#include <osg/PointSprite>
+
+using namespace osg;
+
+int PointSprite::compare(const StateAttribute& sa) const
+{
+    // check the types are equal and then create the rhs variable
+    // used by the COMPARE_StateAttribute_Paramter macro's below.
+    COMPARE_StateAttribute_Types(PointSprite,sa)
+    return 0; // passed all the above comparison macro's, must be equal.
+}
+
+void PointSprite::getAssociatedModes(std::vector<GLMode>& modes) const
+{
+    modes.push_back(GL_POINT_SPRITE_ARB);
+}
+
+void PointSprite::apply(osg::State&) const
+{
+    glTexEnvi(GL_POINT_SPRITE_ARB, GL_COORD_REPLACE_ARB, 1);
+}