Introduced optional build against the GLU library, using optional compile paths to enable/disable GLU related function.

To toggle the use of the GLU library adjust the OSG_GLU_AVAILABLE variable via ccmake . or CMakeSetup.

include/osg/GLU

@@ -14,19 +14,25 @@
 #ifndef OSG_GLU
 #define OSG_GLU 1
 
-#include <osg/GL>
+#include <osg/Config>
 
-#if defined(__APPLE__) || \
-    (defined (_AIX) && !defined (_AIX51))
-    #include <OpenGL/glu.h>
-#else
-    #include <GL/glu.h>
-#endif
+#ifdef OSG_GLU_AVAILABLE
+
+    #include <osg/GL>
+
+    #if defined(__APPLE__) || \
+        (defined (_AIX) && !defined (_AIX51))
+        #include <OpenGL/glu.h>
+    #else
+        #include <GL/glu.h>
+    #endif
+
+    #if defined(GLU_TESS_CALLBACK_TRIPLEDOT)
+        typedef void (APIENTRY *GLU_TESS_CALLBACK)(...);
+    #else
+        typedef void (APIENTRY *GLU_TESS_CALLBACK)();
+    #endif
 
-#if defined(GLU_TESS_CALLBACK_TRIPLEDOT)
-    typedef void (APIENTRY *GLU_TESS_CALLBACK)(...);
-#else
-    typedef void (APIENTRY *GLU_TESS_CALLBACK)();
 #endif
 
 #endif  // __osgGLU_h

include/osgUtil/SceneGraphBuilder

@@ -23,6 +23,19 @@
 
 namespace osgUtil {
 
+#ifndef OSG_GLU_AVAILABLE
+    // as we have no GLU we'll just define the required enum values
+    #define GLU_FALSE           0
+    #define GLU_FILL            100012
+    #define GLU_SMOOTH          100000
+    #define GLU_OUTSIDE         100020
+    #define GLU_NONE            100002
+    #define GLU_POINT           100010
+    #define GLU_LINE            100011
+    #define GLU_FILL            100012
+    #define GLU_SILHOUETTE      100013
+#endif
+
 /** A class for assisting the building ascene graphs that is equivilant to OpenGL 1.0 style calls.
   */
 class OSGUTIL_EXPORT SceneGraphBuilder

include/osgUtil/Tessellator

@@ -42,6 +42,7 @@ class OSGUTIL_EXPORT Tessellator : public osg::Referenced
         ~Tessellator();
 
         /** The winding rule, see red book ch 11. */
+#ifdef OSG_GLU_AVAILABLE
         enum WindingType{
             TESS_WINDING_ODD          = GLU_TESS_WINDING_ODD,
             TESS_WINDING_NONZERO      = GLU_TESS_WINDING_NONZERO     ,
@@ -49,7 +50,15 @@ class OSGUTIL_EXPORT Tessellator : public osg::Referenced
             TESS_WINDING_NEGATIVE     = GLU_TESS_WINDING_NEGATIVE    ,
             TESS_WINDING_ABS_GEQ_TWO  =    GLU_TESS_WINDING_ABS_GEQ_TWO
         } ;
-
+#else
+        enum WindingType{
+            TESS_WINDING_ODD,
+            TESS_WINDING_NONZERO,
+            TESS_WINDING_POSITIVE,
+            TESS_WINDING_NEGATIVE,
+            TESS_WINDING_ABS_GEQ_TWO
+        } ;
+#endif
         /** we interpret all contours in the geometry as a single set to be tessellated or
          * each separate drawable's contours needs to be tessellated. */
         enum TessellationType {
@@ -211,7 +220,11 @@ class OSGUTIL_EXPORT Tessellator : public osg::Referenced
         typedef std::vector<NewVertex> NewVertexList;
         typedef std::vector<Vec3d*> Vec3dList;
 
+#ifdef OSG_GLU_AVAILABLE
         GLUtesselator*  _tobj;
+#else
+        void*           _tobj;
+#endif
         PrimList        _primList;
         Vec3dList       _coordData;
         NewVertexList   _newVertexList;