It is very convenient to represent a light source as a part of a 3D scene. When we write "a 3D scene", we mean a scene graph. In order to attach a light source to a scene graph, we need a special node for it. Here is the clLightNode class that holds a pointer to iLight with all light properties:
class clLightNode: public clSceneNode
{
public:
clLightNode() {}
clPtr<iLight> GetLight() const
{
return m_Light;
}
void SetLight( const clPtr<iLight>& L )
{
m_Light = L;
}
virtual void AcceptTraverser( iSceneTraverser* Traverser )
override;
clPtr<iLight> m_Light;
};The AcceptTraverser() method is similar to those in clGeometryNode and clMaterialNode. But this time, we will call the PreAcceptLightNode() and PostAcceptLightNode() methods of iSceneTraverser:
void clLightNode::AcceptTraverser( iSceneTraverser* Traverser )
{
Traverser->PreAcceptSceneNode( this );
Traverser->PreAcceptLightNode( this );
AcceptChildren...