NAME

Point − coordinate position

SYNOPSIS

include    "draw.m";
draw := load Draw Draw->PATH;
 Point: adt
{
    x:    int;
    y:    int;
     add:  fn(p: self Point, q: Point):  Point;
    sub:  fn(p: self Point, q: Point):  Point;
    mul:  fn(p: self Point, i: int):    Point;
    div:  fn(p: self Point, i: int):    Point;
    eq:   fn(p: self Point, q: Point):  int;
    in:   fn(p: self Point, r: Rect):   int;
};

DESCRIPTION

The ­Point data type specifies a position in the integer grid. 

x, y The coordinate position. The coordinates increase to the right (x) and down (y).

p.add(q) Returns the point (p.x+q.x, p.y+q.y). 

p.sub(q) Returns the point (p.x−q.x, p.y−q.y). 

p.mul(i) Returns the point (p.x∗i, p.y∗i). 

p.div(i) Returns the point (p.x/i, p.y/i). 

p.eq(q) Returns non-zero if the points’ coordinates are equal and zero otherwise. 

p.in(r) Returns non-zero if point ­p lies within rectangle ­r and zero otherwise. 

SEE ALSO

draw-intro(2), draw-rectangle(2)

Plan 9  —  June 29, 2000