Definition
An instance r of the data type rat_ray is a directed straight ray defined by two points with rational coordinates in the two-dimensional plane.
Creation
| rat_ray | r(rat_point p, rat_point q); | |
| introduces a variable r of type rat_ray. r is initialized to the
ray starting at point p and passing through point q. Precondition: p != q. |
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| rat_ray | r(rat_segment s); | introduces a variable r of type rat_ray. r is initialized to the
(rat_ray(s.source(),s.target()).
Precondition: s is nontrivial. |
rat_ray |
r; | introduces a variable r of type rat_ray. |
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Operations
| ray | r.to_ray() | returns a floating point approximation of r. |
| rat_point | r.source() | returns the source of r. |
| rat_point | r.point1() | returns the source of r. |
| rat_point | r.point2() | returns a point on r different from r.source(). |
| bool | r.is_vertical() | returns true iff r is vertical. |
| bool | r.is_horizontal() | returns true iff r is horizontal. |
| bool | r.intersection(rat_ray s, rat_point& inter) | |
| returns true if r and s intersect. If so, a point of intersection is returned in inter. | ||
| bool | r.intersection(rat_segment s, rat_point& inter) | |
| returns true if r and s intersect. If so, a point of intersection is returned in inter. | ||
| rat_ray | r.translate(rational dx, rational dy) | |
| returns r translated by vector (dx,dy). | ||
| rat_ray | r.translate(integer dx, integer dy, integer dw) | |
| returns r translated by vector (dx/dw,dy/dw). | ||
| rat_ray | r.translate(rat_vector v) | returns r+v, i.e., r translated by vector v.
Precondition: v.dim() = 2. |
| rat_ray | r + rat_vector v | returns r translated by vector v. |
| rat_ray | r - rat_vector v | returns r translated by vector -v. |
| rat_ray | r.rotate90(rat_point q) | returns r rotated about q by an angle of 90 degrees. |
| rat_ray | r.reflect(rat_point p, rat_point q) | |
| returns r reflected across the straight line passing
through p and q.
Precondition: p != q. |
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| rat_ray | r.reflect(rat_point p) | returns r reflected across point p. |
| rat_ray | r.reverse() | returns r reversed. |
| bool | r.contains(rat_point p) | decides whether r contains p. |
| bool | r.contains(rat_segment s) | decides whether r contains s. |
Non-Member Functions
| int | orientation(rat_ray r, rat_point p) | |
| computes orientation(a, b, p), where a != b and a and b appear in this order on ray r. | ||
| int | cmp_slopes(rat_ray r1, rat_ray r2) | |
| returns compare(slope(r_1), slope(r_2)). | ||