public class Polyhedron extends Surface{

    Plane[] faces;
    int n;//nb of faces
    Vector currentNormalIn;//normal of entry for the point being observed
    Vector currentNormalOut;
   
    Polyhedron(){
    }
    Polyhedron(Plane[] s){


	n=s.length;
	faces=new Plane[n];
	for (int i=0;i<n;i++){
	    faces[i]=new Plane(s[i]);
	}
	m=new material();
	m.copy(faces[0].m);
    }

    void cube(material ms){
    faces=new Plane[6];
    m=new material();
    m.copy(ms);
    faces[0]=new Plane(new double[] {-1,0,0,-1},m);
    faces[1]=new Plane(new double[] {1,0,0,-1},m);
    faces[2]=new Plane(new double[] {0,-1,0,-1},m);
    faces[3]=new Plane(new double[] {0,1,0,-1},m);
    faces[4]=new Plane(new double[] {0,0,-1,-1},m);
    faces[5]=new Plane(new double[] {0,0,1,-1},m);


    }

    double[] intersections(double[]v, double[]w){
	double tIn=-1;
	double tOut=INFTY+1;
	int indIn=-1;
	int indOut=-1;
	for (int i=0; i<faces.length; i++){
	    double[] tmpt=faces[i].intersections(v,w);
	    if (tIn<tmpt[0]){
		tIn=tmpt[0];
		indIn=i;
	    }
	    if (tOut>tmpt[1]){
		tOut=tmpt[1];
		indOut=i;
	    }
	}
	double[] res=new double[2];
	res[0]=tIn;
	res[1]=tOut;
	if (tIn>-1){
	    currentNormalIn=new Vector(faces[indIn].extNormal);
	    m=faces[indIn].m;
	}
	if (tOut<=INFTY){
	    currentNormalOut=new Vector(faces[indOut].extNormal);
	}
	return res;

    }

    void setTransfo(Matrix3D tfs){
	for (int i=0;i<n;i++){
	    faces[i].setTransfo(tfs);
	}
    }


    public double[] shade(Surface[] obj, Light[] lights, double[] v, double[] ws, double t, int howManyRefl, hw9 calling){
	Vector w0=new Vector(ws);
	w0.normalize();
	double[] w=w0.v;	
	double[] res = new double[] {0,0,0};
	double[] currPt=new double[3];
	for (int i=0; i<3; ++i){
	    currPt[i]=v[i]+t*w[i];
	    res[i]=m.ambient[i];
	}
	Vector normV=currentNormalIn;
	
	if (lights!=null){
	    for (int i=0; i<lights.length;i++){
		int shadowed=0;
		Vector tmp=lights[i].dir.scalMult(0.01);
		Vector newSource=tmp.add(new Vector(currPt));	    
		for (int ii=0; ii<obj.length; ii++){
		    double[] tTmpTab=obj[ii].intersections(newSource.v,lights[i].dir.v);
		    double tTmp=tTmpTab[0];
		    double tTmpOut=tTmpTab[1];
		    if(tTmp>=tTmpOut) continue;
		    if (tTmp>0 & tTmp<9995){
			shadowed=1;
			break;			
		    }
		}
		if (shadowed==1){
		    continue;
		}
		
		for (int j=0;j<3;j++){
		    double vald=lights[i].dir.dotP(normV);
		    if (vald>0)
			res[j]+=lights[i].rgb[j]*m.diffuse[j]*vald;// diffuse
			
		    tmp=normV.scalMult(2*vald);		

		    double vals=e0.dotP(tmp.diff(lights[i].dir));
		    if (vals>0)
			res[j]+=lights[i].rgb[j]*m.specular[j]*Math.pow(vals,m.p);
		    
 				    
		}


	    }
	}

	//now reflection
		if (howManyRefl>0){
		    Vector newW=new Vector(w);
		    newW=newW.diff(normV.scalMult(2*normV.dotP(w)));
		    newW.normalize();
		    Vector newV=new Vector(currPt);
		    newV=newV.add(newW.scalMult(0.001));

		    double[] tmpRef=calling.rayTraceSurf(newV.v, newW.v, howManyRefl-1, 1);
		    tmpRef[0]*=m.specular[0];
		    tmpRef[1]*=m.specular[1];
		    tmpRef[2]*=m.specular[2];
		    res[0]+=tmpRef[0];
		    res[1]+=tmpRef[1];
		    res[2]+=tmpRef[2];

	    //res=add(res,calling.rayTrace(newV, newW, howManyRefl-1));
	    //res=diff(add(res,calling.rayTrace(newV, newW, howManyRefl-1)), m.ambient);
	    }
	//...and refraction

	return res;
    }




}