package core;

//takes a pixel position from a rasterized polygon and find its 3D location in world space

public class Turn2DTo3DFactory {

public vector O, U, V, W, A, B, C;

public vector location3D;

public float X, Y;

public void init(){

O = new vector(0,0,0);

U = new vector(0,0,0);

V = new vector(0,0,0);

W = new vector(0,0,0);

A = new vector(0,0,0);

B = new vector(0,0,0);

C = new vector(0,0,0);

location3D = new vector(0,0,0);

}

public vector get3DLocation(polygon3D poly, int x, int y){

O.set(poly.origin);

O.subtract(camera.position);

O.rotate_XZ(camera.XZ_angle);

O.rotate_YZ(camera.YZ_angle);

U.set(poly.rightEnd);

U.subtract(camera.position);

U.rotate_XZ(camera.XZ_angle);

U.rotate_YZ(camera.YZ_angle);

V.set(poly.bottomEnd);

V.subtract(camera.position);

V.rotate_XZ(camera.XZ_angle);

V.rotate_YZ(camera.YZ_angle);

U.subtract(O);

U.unit();

V.subtract(O);

V.unit();

A.cross(V,O);

B.cross(O,U);

C.cross(U,V);

W.set(x-384, -y + 256, 650);

X = A.dot(W)/C.dot(W);

Y = B.dot(W)/C.dot(W);

O.set(poly.origin);

U.set(poly.rightEnd);

V.set(poly.bottomEnd);

U.subtract(O);

V.subtract(O);

X/=(U.getLength());

Y/=(V.getLength());

location3D.set(O);

location3D.add(U, X);

location3D.add(V, Y);

return location3D;

}

}