class Psychlops::Rectangle

Usage

Typically, a rectangle is designate its size by set and move to relative coordinate to center of window by centering and shift functions.

Typical usage:

Psychlops::Rectangle rect;
rect.set(100, 100).centering().shift(-100, 0);
rect.draw(Color::red);

Functions

Initialization

By decralation

Rectangle()

set the rectangle’s size as 0 * 0.

Rectangle(double left, double top, double right, double bottom)

Rectangle(double width, double height)

set the rectangle’s size as width * height. Left-Top corner is placed on (0,0).

By function

Rectangle& set(double left, double top, double right, double bottom)

Rectangle& set(double width, double height)

set the rectangle’s size as width * height. Left-Top corner is placed on (0,0).

Rectangle& resize(double width, double height)

resize the rectangle’s size as width * height. Center of the rectangle will be kept.

Translation

Rectangle& centering()

place the rectangle at center of the window.

Rectangle& centering(double x, double y)

Rectangle& centering(Point new_center)

place the rectangle centered at (x,y) or (new_center.x, new_center.y). Typically, the function is used with getCenter() as rect.centering(image.getCenter()).

Rectangle& shift(double h, double v)

move the rectangle by (h, v).

Getting parameters

• double getWidth()
• double getHeight()
• Point getCenter()
• double getTop()
• double getLeft()
• double getBottom()
• double getRight()

Drawing

void draw(color)

draw the ellipse with designated Color;

Checking inclusion

These functions check whether the Rectangle instance includes other points in its area. The Rectangle instance is treated as closed set (= returns true if the point on the boundary line).

bool include(double x, double y)

bool include(Point other)