Added releaseGLObjects to NodeCallbacks, Drawable::DrawCallbacks and wired up

osgProducer to use it when doing cleanup_frame.

Make/dependencies

@@ -30,6 +30,8 @@ QT4_ROOT ?= /usr/local/
 
 SDL_INSTALLED ?= no
 
+FLTK_INSTALLED ?= no
+
 ifeq ($(OS),Darwin)
     DARWIN_QUICKTIME ?= yes
 endif

Make/makedirdefs

@@ -285,6 +285,7 @@ endif
 ifeq ($(GLUT_INSTALLED),yes)
     EXAMPLE_DIRS += osgGLUTsimple
     EXAMPLE_DIRS += osgGLUTkeyboardmouse
+    EXAMPLE_DIRS += osgsimpleviewerGLUT
 endif
 
 ifeq ($(QT3_INSTALLED),yes)
@@ -298,3 +299,11 @@ endif
 ifeq ($(SDL_INSTALLED),yes)
     EXAMPLE_DIRS += osgsimpleviewerSDL
 endif
+
+ifeq ($(FLTK_INSTALLED),yes)
+    EXAMPLE_DIRS += osgsimpleviewerFLTK
+endif
+
+ifeq ($(PRODUCER_INSTALLED),yes)
+    EXAMPLE_DIRS += osgsimpleviewerProducer
+endif