#pragma once

#include <vector>
#include "Vector.hpp"
#include "Transformed.h"
class Mesh;
class SubMesh;
class Entity;
class RenderStrategy;

class SubEntity
{
	friend class FinalCompositionRenderStrategy;

protected:
	Entity*				parent;
	int					nNearClusters;

	SubMesh*			subMesh;		//!< mesh
	Transformed*		rayTraceEntity;	//!< raytracable entity containing the subMesh's TriangleMesh
	
	LPDIRECT3DTEXTURE9 prmTexture;		//!< a collection of tiled UV atlases containing illuminaton contributions of nearest entry point clusters
	LPDIRECT3DSURFACE9 prmSurface;		//!< prmTexture's surface

	int					prmxres;
	int					prmyres;

	void createRayTraceEntity();		//!< setup rayTraceEntity

	//! array of cluster indices storing which clusters are relevant. PRM tiles correspond to these clusters
	unsigned int nearClusterIndices[32];


public:
	//! clear PRM to float4(0, 0, 0, 0)
	void clearPRM();

	//! render contributions of virtual light sources in 'bushRadions' to atlas corresponding to cluster 'bushId'
	void renderPRM(	std::vector<Radion>& clusterRadions, unsigned int clusterId);

	//! downscale pixel values according to alpha (render-to-the-pixel counter) to get rid of overlapping edge artifacts
	void normalizePRM();

	//! fill the nearClusterIndices array
	void findNearClusters(const std::vector<Radion>& starters, unsigned int nClusters);

public:
	SubEntity(Entity* parent, SubMesh* subMesh, int nNearClusters);
	~SubEntity(void);

	Intersectable* getRayTraceEntity();

	void draw(const RenderStrategy& renderStrategy);
	float getSurfaceArea();
	const Material* sampleSurface(Radion& sample);

	void savePRM();
	void loadPRM();

	void saveSceneInfo(std::ofstream& psf);
};