[FIX] - fixes offscreen render problem on MacOS X

src/graphicsEngine/WGEOffscreenFinalPass.cpp

@@ -34,6 +34,17 @@ WGEOffscreenFinalPass::WGEOffscreenFinalPass( size_t textureWidth, size_t textur
     // initialize members
     setRenderTargetImplementation( osg::Camera::FRAME_BUFFER );
     setRenderOrder( osg::Camera::NESTED_RENDER, 0 );
+
+    // render before the hud
+    if ( m_hud )
+    {
+        getOrCreateStateSet()->setRenderBinDetails( m_hud->getRenderBin() - 1, "RenderBin" );
+    }
+    else
+    {
+        getOrCreateStateSet()->setRenderBinDetails( 10000, "RenderBin" );
+    }
+
     osg::StateSet* state = this->getOrCreateStateSet();
     state->setMode( GL_DEPTH_TEST, osg::StateAttribute::ON );
 }
@@ -45,6 +56,17 @@ WGEOffscreenFinalPass::WGEOffscreenFinalPass( size_t textureWidth, size_t textur
     // initialize members
     setRenderTargetImplementation( osg::Camera::FRAME_BUFFER );
     setRenderOrder( osg::Camera::NESTED_RENDER, 0 );
+
+    // render before the hud
+    if ( m_hud )
+    {
+        getOrCreateStateSet()->setRenderBinDetails( m_hud->getRenderBin() - 1, "RenderBin" );
+    }
+    else
+    {
+        getOrCreateStateSet()->setRenderBinDetails( 10000, "RenderBin" );
+    }
+
     osg::StateSet* state = this->getOrCreateStateSet();
     state->setMode( GL_DEPTH_TEST, osg::StateAttribute::ON );
 }

src/graphicsEngine/WGEOffscreenRenderPass.cpp

@@ -91,7 +91,11 @@ osg::ref_ptr< osg::Texture2D > WGEOffscreenRenderPass::attach( BufferComponent b
     }
     else
     {
+#if defined(__APPLE__)
+        tex = createTexture( GL_RGBA );           // on MacOS X, only RGBA textures work as attachment for FBO's
+#else
         tex = createTexture( internalFormat );
+#endif
     }
     attach( buffer, tex );
     return tex;

src/graphicsEngine/WGETextureHud.cpp

@@ -44,10 +44,11 @@ WGETextureHud::WGETextureHud():
     osg::Projection(),
     m_group( new WGEGroupNode() ),
     m_maxElementWidth( 256 ),
+    m_renderBin( 10000 ),
     m_viewport( new osg::Viewport() ),
     m_coupleTexViewport( false )
 {
-    getOrCreateStateSet()->setRenderBinDetails( 1000, "RenderBin" );
+    getOrCreateStateSet()->setRenderBinDetails( m_renderBin, "RenderBin" );
     m_group->addUpdateCallback( new SafeUpdateCallback( this ) );
     addChild( m_group );
 }
@@ -310,3 +311,8 @@ osg::ref_ptr< osg::Texture2D > WGETextureHud::WGETextureHudEntry::getTexture() c
     return m_texture;
 }
 
+size_t WGETextureHud::getRenderBin() const
+{
+    return m_renderBin;
+}
+

src/graphicsEngine/WGETextureHud.h

@@ -183,6 +183,13 @@ public:
      */
     void coupleViewportWithTextureViewport( bool couple = true );
 
+    /**
+     * Returns the render bin used by the HUD.
+     *
+     * \return the bin number
+     */
+    size_t getRenderBin() const;
+
 protected:
 
     /**
@@ -196,6 +203,11 @@ protected:
      */
     unsigned int m_maxElementWidth;
 
+    /**
+     * The render bin to use
+     */
+    size_t m_renderBin;
+
     /**
      * The current viewport of
      */

src/graphicsEngine/shaders/WGEUtils.glsl

@@ -45,8 +45,22 @@ float scaleZeroOne( in float threshold, in float min, in float max )
  * 
  * \return true if zero.
  */
-bool isZero( in float value, in float epsilon = 0.001 )
+bool isZero( in float value, in float epsilon )
 {
     return ( abs( value ) <= epsilon );
 }
 
+/**
+ * Evaluates a given value whether it is zero, or more exactly, if it can be seen as zero.
+ * \note This version is needed for portability as the GLSL compiler on MacOS X does not allow argument default values in functions.
+ *
+ * \param value the value to check
+ * \param epsilon the epsilon to use. Default is 0.001. Much lower is not recommended since floating point precision in GLSL is not that high.
+ * 
+ * \return true if zero.
+ */
+bool isZero( in float value )
+{
+    return ( abs( value ) <= 0.001 );
+}
+