/**
* Sets the height of this rectangle to a given value. The rectangle will expand or contract,
* equally on both sides to reach the given height.
*
* @param height A value, greater than or equal to 0, to which this rectangle's height will be
* set.
* @throws IllegalArgumentException If <code>height</code> is less than 0.
*/
public void setHeight(double height) {
// negative height?
if (height < 0)
throw new IllegalArgumentException("Invalid rectangle height: Cannot " + "be less than 0.");
// store all vertices for easy access
Vector2D v1 = getVertex(0);
Vector2D v2 = getVertex(1);
Vector2D v3 = getVertex(2);
Vector2D v4 = getVertex(3);
// compute the change in height
double delta = height - this.height;
// find the direction of v1 to v2
Vector2D v1v2 = v2.subtract(v1);
// determine changes for vertices
Vector2D delta2And3 = new Vector2D(v1v2, delta / 2);
Vector2D delta1And4 = delta2And3.inverse();
// apply changes
v1 = v1.add(delta1And4);
v2 = v2.add(delta2And3);
v3 = v3.add(delta2And3);
v4 = v4.add(delta1And4);
// set new vertices
LinkedList<Vector2D> verts = new LinkedList<Vector2D>();
verts.add(v1);
verts.add(v2);
verts.add(v3);
verts.add(v4);
setVertices(verts);
}
/**
* Sets the width of this rectangle to a given value. The rectangle will expand or contract,
* equally on both sides to reach the given width.
*
* @param width A value, greater than or equal to 0, to which this rectangle's width will be set.
* @throws IllegalArgumentException If <code>width</code> is less than 0.
*/
public void setWidth(double width) {
// negative width?
if (width < 0)
throw new IllegalArgumentException("Invalid rectangle width: Cannot " + "be less than 0.");
// store all vertices for easy access
Vector2D v1 = getVertex(0);
Vector2D v2 = getVertex(1);
Vector2D v3 = getVertex(2);
Vector2D v4 = getVertex(3);
// compute the change in width
double delta = width - this.width;
// find the direction of v2 to v3
Vector2D v2v3 = v3.subtract(v2);
// determine changes for vertices
Vector2D delta3And4 = new Vector2D(v2v3, delta / 2);
Vector2D delta1And2 = delta3And4.inverse();
// apply changes
v1 = v1.add(delta1And2);
v2 = v2.add(delta1And2);
v3 = v3.add(delta3And4);
v4 = v4.add(delta3And4);
// set new vertices
LinkedList<Vector2D> verts = new LinkedList<Vector2D>();
verts.add(v1);
verts.add(v2);
verts.add(v3);
verts.add(v4);
setVertices(verts);
}