/** Simple checkerboard texture
 * 3D material, works best for non-moving objects
 * @author: Phil Gage
 */
class CheckerMaterial extends Material {
    Color color2;       // alternate checker grid square color
    int gridSize = 10;  // spacing of checker grid

    CheckerMaterial (Color color, Color color2, int gridSize) {
        super(color);
        this.color2 = color2;
        this.gridSize = gridSize;
    }

    /** Return 3D checker texture color based on location */
    Color getColor (Point point) {
        // Add 1000 to avoid wide squares at origin
        if (((int)(point.x+1000)/gridSize +
             (int)(point.y+1000)/gridSize +
             (int)(point.z+1000)/gridSize) % 2 == 0)
            return color;
        else
            return color2;
    }

}