void
ShaderGenerator::apply( osg::Geode& node )
{
if ( !_active )
return;
bool ignore;
if ( node.getUserValue(SHADERGEN_HINT_IGNORE, ignore) && ignore )
return;
osg::ref_ptr<osg::StateSet> stateset = node.getStateSet();
if ( stateset.valid() )
{
_state->pushStateSet( stateset.get() );
}
unsigned numDrawables = node.getNumDrawables();
bool traverseDrawables = true;
// This block checks whether all the geode's drawables are equivalent,
// i.e., they are the same type (geometry or text) and none of them
// have their own state sets. IF that's the case, we can create a
// single shader program for the entire geode. This is an optimization.
if ( stateset.valid() )
{
unsigned d;
unsigned numInheritingText = 0, numInheritingGeometry = 0;
for( d = 0; d < numDrawables; ++d )
{
osg::Drawable* drawable = node.getDrawable(d);
if ( drawable->getStateSet() == 0L )
{
if ( drawable->asGeometry() )
numInheritingGeometry++;
else if ( dynamic_cast<osgText::Text*>(drawable) )
numInheritingText++;
}
}
if (numInheritingGeometry == numDrawables )
{
osg::ref_ptr<osg::StateSet> replacement;
if ( processGeometry(stateset.get(), replacement) )
{
node.setStateSet(replacement.get() );
traverseDrawables = false;
}
}
else if (numInheritingText == numDrawables )
{
osg::ref_ptr<osg::StateSet> replacement;
if ( processText(stateset.get(), replacement) )
{
node.setStateSet(replacement.get() );
traverseDrawables = false;
}
}
}
// Drawables have state sets, so let's traverse them.
if ( traverseDrawables )
{
for( unsigned d = 0; d < node.getNumDrawables(); ++d )
{
apply( node.getDrawable(d) );
}
}
if ( stateset.valid() )
{
_state->popStateSet();
}
}
