add an OpenGL module simplifying the way you can pass Eigen's objects to GL

unsupported/test/openglsupport.cpp

@@ -0,0 +1,61 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2010 Gael Guennebaud <gael.guennebaud@inria.fr>
+//
+// Eigen is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Lesser General Public
+// License as published by the Free Software Foundation; either
+// version 3 of the License, or (at your option) any later version.
+//
+// Alternatively, you can redistribute it and/or
+// modify it under the terms of the GNU General Public License as
+// published by the Free Software Foundation; either version 2 of
+// the License, or (at your option) any later version.
+//
+// Eigen 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 GNU Lesser General Public License or the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License and a copy of the GNU General Public License along with
+// Eigen. If not, see <http://www.gnu.org/licenses/>.
+
+#include <iostream>
+#include <GL/glut.h>
+#include <Eigen/OpenGLSupport>
+using namespace Eigen;
+
+int main(int argc, char **argv)
+{
+  glutInit(&argc, argv);
+  glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
+  glutInitWindowPosition (0,0);
+  glutInitWindowSize(10, 10);
+
+  if(glutCreateWindow("Eigen") <= 0)
+  {
+    std::cerr << "Unable to create GLUT Window.\n";
+    exit(1);
+  }
+
+  Vector3f v3f;
+  Matrix3f rot;
+  glBegin(GL_POINTS);
+  
+  glVertex(v3f);
+  glVertex(2*v3f+v3f);
+  glVertex(rot*v3f);
+  
+  glEnd();
+  
+  Quaterniond qd;
+  glRotate(qd);
+  
+  Matrix4f m44;
+  glLoadMatrix(m44);
+  glMultMatrix(m44);
+  
+  return 0;
+}