Definition
An instance l of the data type
rat
line is a directed straight line
in the two-dimensional plane.
#include < LEDA/rat _line.h >
Creation
| rat_line | l(rat_point p, rat_point q) | |
| introduces a variable l of type rat_line. l is initialized to the
line passing through points p and q directed form p to q.
Precondition: p! = q. |
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| rat_line | l(rat_segment s) | introduces a variable l of type rat_line. l is initialized to the
line supporting segment s.
Precondition: s is nontrivial. |
| rat_line | l(rat_point p, rat_vector v) | |
| introduces a variable l of type rat_line. l is initialized to the
line passing through points p and p + v.
Precondition: v is a nonzero vector. |
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| rat_line | l(rat_ray r) | introduces a variable l of type rat_line. l is initialized to the line supporting ray r. |
| rat_line | l | introduces a variable l of type rat_line. |
| rat_line | l(line l, int prec = rat_point::default_precision) | |
| introduces a variable l of type rat_line. l is initialized to the line obtained by approximating the two defining points of l. | ||
Operations
| line | l.to_line() | returns a floating point approximation of l. |
| rat_point | l.point1() | returns a point on l. |
| rat_point | l.point2() | returns a second point on l. |
| rat_segment | l.seg() | returns a segment on l. |
| bool | l.is_vertical() | decides whether l is vertical. |
| bool | l.is_horizontal() | decides whether l is horizontal. |
| bool | l.intersection(rat_line g, rat_point& inter) | |
| returns true if l and g intersect. In case of intersection a common point is returned in inter. | ||
| bool | l.intersection(rat_segment s, rat_point& inter) | |
| returns true if l and s intersect. In case of intersection a common point is returned in inter. | ||
| rat_line | l.translate(rational dx, rational dy) | |
| returns l translated by vector (dx, dy). | ||
| rat_line | l.translate(integer dx, integer dy, integer dw) | |
| returns l translated by vector (dx/dw, dy/dw). | ||
| rat_line | l.translate(rat_vector v) | returns l translated by vector v.
Precondition: v.dim() = 2. |
| rat_line | l + rat_vector v | returns l translated by vector v. |
| rat_line | l - rat_vector v | returns l translated by vector - v. |
| rat_line | l.rotate90(rat_point q) | returns l rotated about q by an angle of 90 degrees. |
| rat_line | l.reflect(rat_point p, rat_point q) | |
| returns l reflected across the straight line passing through p and q. | ||
| rat_line | l.reverse() | returns l reversed. |
| rational | l.sqr_dist(rat_point q) | returns the square of the distance between l and q. |
| rat_segment | l.perpendicular(rat_point p) | |
| returns the segment perpendicular to l with source p and target on l. | ||
| int | l.side_of(rat_point p) | computes orientation(a, b, p), where a! = b and a and b appear in this order on line l. |
| bool | l.contains(rat_point p) | returns true if p lies on l. |
| bool | l.clip(rat_point p, rat_point q, rat_segment& s) | |
| clips l at the rectangle R defined by p and q. Returns true if the intersection of R and l is non-empty and returns false otherwise. If the intersection is non-empty the intersection is assigned to s; It is guaranteed that the source node of s is no larger than its target node. | ||
| bool | l == g | returns true if the l and g are equal as oriented lines. |
| bool | equal_as_sets(rat_line l, rat_line g) | |
| returns true if the l and g are equal as unoriented lines. | ||
Non-Member Functions
| int | orientation(rat_line l, rat_point p) | |
| computes orientation(a, b, p), where a! = b and a and b appear in this order on line l. | ||
| int | cmp_slopes(rat_line l1, rat_line l2) | |
| returns compare(slope(l1), slope(l2)). | ||
| rat_line | p_bisector(rat_point p, rat_point q) | |
| returns the perpendicular bisector of p and q. The bisector has p on its left.
Precondition: p! = q. |
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