Merged fixes to the osg::GLExtensions function pointer code from Stefan Huber,

and a fix to osg::State's secondary color code from Bob Kuehne.

Moved the body of the getGLExtensionFuncPtr() into the header to help out
support for Windows mapping of different OpenGL extensions function ptr per
dll.

include/osg/GLExtensions

@@ -7,6 +7,14 @@
 
 #include <osg/Export>
 
+#if defined(WIN32)
+#include <windows.h>
+#elif defined(__DARWIN_OSX__)
+#include <mach-o/dyld.h>
+#else
+#include <dlfcn.h>
+#endif
+
 namespace osg {
 
 /** return true if OpenGL "extension" is supported.
@@ -17,8 +25,36 @@ SG_EXPORT extern const bool isGLExtensionSupported(const char *extension);
 
 /** return the address of the specified OpenGL function.
   * return NULL if function not supported by OpenGL library.
+  * Note, glGLExtensionFuncPtr is declared inline so that the code
+  * is compiled localy to the calling code.  This should get by Windows
+  * dumb implementation of having different GL function ptr's for each
+  * library when links to it. 
   */
-SG_EXPORT extern void* getGLExtensionFuncPtr(const char *funcName);
+inline void* getGLExtensionFuncPtr(const char *funcName)
+{
+#if defined(WIN32)
+    return wglGetProcAddress(funcName);
+#elif defined(__DARWIN_OSX__)
+    std::string temp( "_" );
+    temp += funcName;	// Mac OS X prepends an underscore on function names
+    if ( NSIsSymbolNameDefined( temp.c_str() ) )
+    {
+        NSSymbol symbol = NSLookupAndBindSymbol( temp.c_str() );
+        return NSAddressOfSymbol( symbol );
+    } else
+	return NULL;
+#else // all other unixes
+   // Note: although we use shl_load() etc. for Plugins on HP-UX, it's
+   // not neccessary here since we only used them because library
+   // intialization was not taking place with dlopen() which renders
+   // Plugins useless on HP-UX.
+   static void *lib = dlopen("libGL.so", RTLD_LAZY);
+   if (lib)
+      return dlsym(lib, funcName);
+   else
+      return NULL;
+#endif
+}
 
 /** return the address of the specified OpenGL function, if not found then
   * check a second function name, if this fails then return NULL as function is

src/osg/GLExtensions.cpp

@@ -1,10 +1,3 @@
-#if defined(WIN32)
-#include <windows.h>
-#elif defined(__DARWIN_OSX__)
-#include <mach-o/dyld.h>
-#else
-#include <dlfcn.h>
-#endif
 
 #include <osg/GL>
 #include <osg/GLExtensions>
@@ -58,27 +51,3 @@ const bool osg::isGLExtensionSupported(const char *extension)
 
     return result;
 }
-
-
-void* osg::getGLExtensionFuncPtr(const char *funcName)
-{
-#if defined(WIN32)
-   return wglGetProcAddress(funcName);
-#elif defined(__DARWIN_OSX__)
-    std::string temp( "_" );
-    NSSymbol symbol;
-    temp += funcName;	// Mac OS X prepends an underscore on function names
-    symbol = NSLookupAndBindSymbol( temp.c_str() );
-    return NSAddressOfSymbol( symbol );
-#else // all other unixes
-   // Note: although we use shl_load() etc. for Plugins on HP-UX, it's
-   // not neccessary here since we only used them because library
-   // intialization was not taking place with dlopen() which renders
-   // Plugins useless on HP-UX.
-   static void *lib = dlopen("libGL.so", RTLD_LAZY);
-   if (lib)
-      return dlsym(lib, funcName);
-   else
-      return NULL;
-#endif
-}

src/osg/Geometry.cpp

@@ -241,7 +241,6 @@ void Geometry::drawImmediateMode(State& state)
         }
     }
     
-    
     static SecondaryColor3ubvProc s_glSecondaryColor3ubv =
             (SecondaryColor3ubvProc) osg::getGLExtensionFuncPtr("glSecondaryColor3ubv","glSecondaryColor3ubvEXT");
     static SecondaryColor3fvProc s_glSecondaryColor3fv =

src/osg/State.cpp

@@ -469,7 +469,7 @@ void State::setSecondaryColorPointer( GLint size, GLenum type,
                                       GLsizei stride, const GLvoid *ptr )
 {
     static SecondaryColorPointerProc s_glSecondaryColorPointer =
-            (SecondaryColorPointerProc) osg::getGLExtensionFuncPtr("glFogCoordPointer","glFogCoordPointerEXT");
+            (SecondaryColorPointerProc) osg::getGLExtensionFuncPtr("glSecondaryColorPointer","glSecondaryColorPointerEXT");
 
     if (s_glSecondaryColorPointer)
     {