org.opentripplanner.common.geometry

Interface IsolineBuilder.ZMetric<TZ>

All Known Implementing Classes:

SampleGridRenderer.WTWD.IsolineMetric

Enclosing interface:

IsolineBuilder<TZ>

public static interface IsolineBuilder.ZMetric<TZ>

A ZMetric is a metric for some generic TZ value. By metric here we understand:

• Cutting detection on a range, z0 in [Za, Zb] (rely on TZ to be an ordered set)
• Interpolation on a range, z0 in [Za, Zb].

Cutting detection could be easily implemented using interpolation, but usually interpolating is rather more expansive than cutting detection so we split the two operations.

Author:

laurent

Method Summary

Modifier and Type	Method and Description
int	cut(TZ zA, TZ zB, TZ z0) Check if the edge [AB] between two samples A and B "intersect" the zz0 plane.
double	interpolate(TZ zA, TZ zB, TZ z0) Interpolate a crossing point on an edge [AB].

Method Detail

cut

int cut(TZ zA,
        TZ zB,
        TZ z0)

Check if the edge [AB] between two samples A and B "intersect" the zz0 plane.

Parameters:

zA - z value for the A sample

zB - z value for the B sample

z0 - z value for the intersecting plane

Returns:

0 if no intersection, -1 or +1 if intersection (depending on which is lower, A or B).

interpolate

double interpolate(TZ zA,
                   TZ zB,
                   TZ z0)

Interpolate a crossing point on an edge [AB].

Parameters:

zA - z value for the A sample

zB - z value for the B sample

z0 - z value for the intersecting plane

Returns:

k value between 0 and 1, where the crossing occurs. 0=A, 1=B.