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Iso-oriented Rectangles ( rectangle )

Definition

An instance r of the data type rectangle is an iso-oriented rectangle in the two-dimensional plane.

#include < LEDA/geo/rectangle.h >

Creation

rectangle r(const point& p, const point& q)
    introduces a variable r of type rectangle. r is initialized to the rectangle with diagonal corners p and q

rectangle r(const point& p, double w, double h)
    introduces a variable r of type rectangle. r is initialized to the rectangle with lower left corner p, width w and height h.

rectangle r(double x1, double y1, double x2, double y2)
    introduces a variable r of type rectangle. r is initialized to the rectangle with diagonal corners (x1,y1) and (x2,y2).

Operations

point r.upper_left() returns the upper left corner.

point r.upper_right() returns the upper right corner.

point r.lower_left() returns the lower left corner.

point r.lower_right() returns the lower right corner.

point r.center() returns the center of r.

list< point> r.vertices() returns the vertices of r in counterclockwise order starting from the lower left point.

double r.xmin() returns the minimal x-coordinate of r.

double r.xmax() returns the maximal x-coordinate of r.

double r.ymin() returns the minimal y-coordinate of r.

double r.ymax() returns the maximal y-coordinate of r.

double r.width() returns the width of r.

double r.height() returns the height of r.

bool r.is_degenerate() returns true, if r degenerates to a segment or point (the 4 corners are collinear), false otherwise.

bool r.is_point() returns true, if r degenerates to a point.

bool r.is_segment() returns true, if r degenerates to a segment.

int r.cs_code(const point& p) returns the code for Cohen-Sutherland algorithm.

bool r.inside(const point& p) returns true, if p is inside of r, false otherwise.

bool r.outside(const point& p) returns true, if p is outside of r, false otherwise.

bool r.inside_or_contains(const point& p)
    returns true, if p is inside of r or on the border, false otherwise.

bool r.contains(const point& p)
    returns true, if p is on the border of r, false otherwise.

region_kind r.region_of(const point& p)
    returns BOUNDED_REGION if p lies in the bounded region of r, returns ON_REGION if p lies on r, and returns UNBOUNDED_REGION if p lies in the unbounded region.

rectangle r.include(const point& p) returns a new rectangle that includes the points of r and p.

rectangle r.include(const rectangle& r2)
    returns a new rectangle that includes the points of r and r2.

rectangle r.translate(double dx, double dy)
    returns a new rectangle that is the translation of r by (dx,dy).

rectangle r.translate(const vector& v)
    returns a new rectangle that is the translation of r by v.

rectangle r + const vector& v returns r translated by v.

rectangle r - const vector& v returns r translated by -v.

point r[int i] returns the i-th vertex of r. Precondition: (0<i<5).

rectangle r.rotate90(const point& p, int i=1)
    returns r rotated about p by an angle of i x 90 degrees. If i > 0 the rotation is counter-clockwise otherwise it is clockwise.

rectangle r.rotate90(int i=1) returns r rotated by an angle of i x 90 degrees about the origin.

rectangle r.reflect(const point& p) returns r reflected across p .

list< point> r.intersection(const segment& s)
    returns r $ \cap$ s .

bool r.clip(const segment& t, segment& inter)
    clips t on r and returns the result in inter.

bool r.clip(const line& l, segment& inter)
    clips l on r and returns the result in inter.

bool r.clip(const ray& ry, segment& inter)
    clips ry on r and returns the result in inter.

bool r.difference(const rectangle& q, list< rectangle> & L)
    returns true iff the difference of r and q is not empty, and false otherwise. The difference L is returned as a partition into rectangles.

list< point> r.intersection(const line& l)
    returns r $ \cap$ l .

list< rectangle> r.intersection(const rectangle& s)
    returns r $ \cap$ s .

bool r.do_intersect(const rectangle& b)
    returns true iff r and b intersect, false otherwise.

double r.area() returns the area of r.


next up previous contents index
Next: Rational Points ( rat_point Up: Basic Data Types for Previous: Triangles ( triangle )   Contents   Index
Christian Uhrig 2017-04-07