// Written by Colin MacDonald - all rights assigned to Nikolaus Gebhardt
// Copyright (C) 2008 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __I_LIGHT_MANAGER_H_INCLUDED__
#define __I_LIGHT_MANAGER_H_INCLUDED__

#include "IReferenceCounted.h"
#include "irrArray.h"

namespace irr
{
namespace scene
{
	class ILightSceneNode;

	//! ILightManager provides an interface for user applications to manipulate the list
	//! of lights in the scene.  The light list can be trimmed or re-ordered before device/
	//! hardware lights are created, and/or individual lights can be switched on and off
	//! before or after each scene node is rendered.
	//! It is assumed that the ILightManager implementation will store any data that it wishes
	//! to retain, i.e. the ISceneManager to which it is assigned, the lightList, the current
	//! render pass, and the current scene node.
	class ILightManager : public IReferenceCounted
	{
	public:
		//! Called after the scene's light list has been built, but before rendering has begun.
		//! As actual device/hardware lights are not created until the ESNRP_LIGHT render pass,
		//! this provides an opportunity for the light manager to trim or re-order the light
		//! list, before any device/hardware lights have actually been created.
		//! \param[in] smgr: the Scene Manager
		//! \param[inout] lightLight: the Scene Manager's light list, which the light manager may
		//!					modify. This reference will remain valid until OnPostRender().
		virtual void OnPreRender(core::array<ILightSceneNode*> & lightList) = 0;

		//! Called after the last scene node is rendered.
		//! After this call returns, the lightList passed to OnPreRender() becomes invalid.
		virtual void OnPostRender(void) = 0;

		//! Called before a render pass begins
		//! \param[in] renderPass: the render pass that's about to begin
		virtual void OnRenderPassPreRender(E_SCENE_NODE_RENDER_PASS renderPass) = 0;

		//! Called after the render pass specified in OnRenderPassPreRender() ends
		//! \param[in] renderPass: the render pass that has finished
		virtual void OnRenderPassPostRender(E_SCENE_NODE_RENDER_PASS renderPass) = 0;

		//! Called before the given scene node is rendered
		//! \param[in] node: the scene node that's about to be rendered
		virtual void OnNodePreRender(ISceneNode* node) = 0;

		//! Called after the the node specified in OnNodePreRender() has been rendered
		//! \param[in] node: the scene node that has just been rendered
		virtual void OnNodePostRender(ISceneNode* node) = 0;
	};
} // end namespace scene
} // end namespace irr

#endif
