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Iso-oriented Real Rectangles ( real_rectangle )

Definition

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

#include < LEDA/geo/real_rectangle.h >

Creation

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

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

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

real_rectangle r(const rectangle& r1, int prec = 0)
    introduces a variable r of type real_rectangle initialized to the rectangle r1. (The second argument is for compatibility with rat_rectangle.)

real_rectangle r(const rat_rectangle& r1)
    introduces a variable r of type real_rectangle initialized to the rectangle r1.

Operations

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

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

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

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

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

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

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

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

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

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

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

real 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 real_point& p)
    returns the code for Cohen-Sutherland algorithm.

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

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

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

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

region_kind r.region_of(const real_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.

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

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

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

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

real_rectangle r + const real_vector& v returns r translated by v.

real_rectangle r - const real_vector& v returns r translated by -v.

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

real_rectangle r.rotate90(const real_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.

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

real_rectangle r.reflect(const real_point& p)
    returns r reflected across p .

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

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

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

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

bool r.difference(const real_rectangle& q, list<real_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<real_point> r.intersection(const real_line& l)
    returns r $ \cap$ l.

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

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

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


next up previous contents index
Next: Geometry Algorithms ( geo_alg Up: Basic Data Types for Previous: Real Triangles ( real_triangle   Contents   Index
root 2008-01-09