public class trapeze extends Shape2{
	final int BOTTOMLEFT=0;
	final int BOTTOMRIGHT=1;
	final int TOPLEFT=3;
	final int TOPRIGHT=2;

	void trapeze(Shape2 triangle, int typ){
		// trapeze: 0,1,2,3 in trigonometric order, starting bottom left
		NVERTICES=4;
		NSIDES=4;
		vertices = new double[NVERTICES][6];
		px=new int[NVERTICES];
		py=new int[NVERTICES];
		pz=new double[NVERTICES];
		rgb=new double[NVERTICES][3];
		if (typ==0){// large base	
			if (triangle.px[triangle.ord[0]]<triangle.px[triangle.ord[1]]){// left-right
				px[BOTTOMLEFT]=triangle.px[triangle.ord[0]];
				py[BOTTOMLEFT]=triangle.py[triangle.ord[0]];
				pz[BOTTOMLEFT]=triangle.pz[triangle.ord[0]];
				for (int i=0;i<3;i++)
					rgb[BOTTOMLEFT][i]=triangle.rgb[triangle.ord[0]][i];
				px[BOTTOMRIGHT]=triangle.px[triangle.ord[1]];
				py[BOTTOMRIGHT]=triangle.py[triangle.ord[1]];
				pz[BOTTOMRIGHT]=triangle.pz[triangle.ord[1]];
				for (int i=0;i<3;i++)
					rgb[BOTTOMRIGHT][i]=triangle.rgb[triangle.ord[1]][i];

			}
			else {//right-left
				px[BOTTOMLEFT]=triangle.px[triangle.ord[1]];
				py[BOTTOMLEFT]=triangle.py[triangle.ord[1]];
				pz[BOTTOMLEFT]=triangle.pz[triangle.ord[1]];
				for (int i=0;i<3;i++)
					rgb[BOTTOMLEFT][i]=triangle.rgb[triangle.ord[1]][i];
				px[BOTTOMRIGHT]=triangle.px[triangle.ord[0]];
				py[BOTTOMRIGHT]=triangle.py[triangle.ord[0]];
				pz[BOTTOMRIGHT]=triangle.pz[triangle.ord[0]];
				for (int i=0;i<3;i++)
					rgb[BOTTOMRIGHT][i]=triangle.rgb[triangle.ord[0]][i];


			}
			px[TOPLEFT]=px[TOPRIGHT]=triangle.px[triangle.ord[2]];
			py[TOPLEFT]=py[TOPRIGHT]=triangle.py[triangle.ord[2]];
			pz[TOPLEFT]=pz[TOPRIGHT]=triangle.pz[triangle.ord[2]];
			for (int i=0;i<3;i++)
				rgb[TOPLEFT][i]=rgb[TOPRIGHT][i]=triangle.rgb[triangle.ord[2]][i];
		}
		if (typ==1){ // large top
			px[BOTTOMLEFT]=px[BOTTOMRIGHT]=triangle.px[triangle.ord[0]];
			py[BOTTOMLEFT]=py[BOTTOMRIGHT]=triangle.py[triangle.ord[0]];
			pz[BOTTOMLEFT]=pz[BOTTOMRIGHT]=triangle.pz[triangle.ord[0]];
			for (int i=0;i<3;i++)
				rgb[BOTTOMLEFT][i]=rgb[BOTTOMRIGHT][i]=triangle.rgb[triangle.ord[0]][i];

			if (triangle.px[triangle.ord[1]]<triangle.px[triangle.ord[2]]){ //left-right
				px[TOPRIGHT]=triangle.px[triangle.ord[2]];
				py[TOPRIGHT]=triangle.py[triangle.ord[2]];
				pz[TOPRIGHT]=triangle.pz[triangle.ord[2]];
				for (int i=0;i<3;i++)
					rgb[TOPRIGHT][i]=triangle.rgb[triangle.ord[2]][i];
				px[TOPLEFT]=triangle.px[triangle.ord[1]];
				py[TOPLEFT]=triangle.py[triangle.ord[1]];
				pz[TOPLEFT]=triangle.pz[triangle.ord[1]];
				for (int i=0;i<3;i++)
					rgb[TOPLEFT][i]=triangle.rgb[triangle.ord[1]][i];
			}


			else {//right-left
				px[TOPRIGHT]=triangle.px[triangle.ord[1]];
				py[TOPRIGHT]=triangle.py[triangle.ord[1]];
				pz[TOPRIGHT]=triangle.pz[triangle.ord[1]];
				for (int i=0;i<3;i++)
					rgb[TOPRIGHT][i]=triangle.rgb[triangle.ord[1]][i];
				px[TOPLEFT]=triangle.px[triangle.ord[2]];
				py[TOPLEFT]=triangle.py[triangle.ord[2]];
				pz[TOPLEFT]=triangle.pz[triangle.ord[2]];
				for (int i=0;i<3;i++)
					rgb[TOPLEFT][i]=triangle.rgb[triangle.ord[2]][i];


			}

		}
	}

	void paintTrapeze(int W, int H){

		double tVer=0;
		double tHor=0;
		int xLeft,xRight;
		int yTop=py[TOPLEFT];
		int yBottom=py[BOTTOMLEFT];
		double rgbzTopLeft[]=getRgbz(TOPLEFT);
		double rgbzTopRight[]=getRgbz(TOPRIGHT);
		double rgbzBottomRight[]=getRgbz(BOTTOMRIGHT);
		double rgbzBottomLeft[]=getRgbz(BOTTOMLEFT);
		for (int y=yBottom;y<yTop+1;++y){
			xLeft=(int)(px[BOTTOMLEFT]+tVer*(px[TOPLEFT]-px[BOTTOMLEFT]));
			xRight=(int)(px[BOTTOMRIGHT]+tVer*(px[TOPRIGHT]-px[BOTTOMRIGHT]));
			double rgbzLeft[]=interpolRgbz(rgbzBottomLeft,rgbzTopLeft,tVer);	
			double rgbzRight[]=interpolRgbz(rgbzBottomRight,rgbzTopRight,tVer);	
			for (int x=xLeft;x<xRight+1;++x){
				double currRgbz[]=interpolRgbz(rgbzLeft,rgbzRight,tHor);	
				if (currRgbz[3]>zBuffer[x][y]){
					zBuffer[x][y]=currRgbz[3];
					for (int i=0;i<3;i++)
						FrameBuffer[x][y][i]=currRgbz[i];
				}
				if (xRight!=xLeft)
					tHor+= 1.0/(xRight-xLeft);
			}
			if (yTop!=yBottom)
				tVer+=1.0/(yTop-yBottom);
		}
	}


}