Name
ST_3DInterpolatePoint — Returns the interpolated measure of a geometry closest to a point in 3D.
Synopsis
float8 ST_3DInterpolatePoint(geometry linear_geom_with_measure, geometry point);
描述
Returns the interpolated measure value of a linear ZM geometry at the location closest to the given point, using 3D (XYZ) distance for the projection. Use this function when the geometry has significant Z variation, such as flight trajectories, where ST_InterpolatePoint would give incorrect results by ignoring the Z dimension.
![[Note]](../images/note.png)
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The line must have both Z and M dimensions. The point should have a Z dimension. |
Availability: 3.7.0
该函数支持 3d 并且不会丢失 z-index。
示例
-- Line rising diagonally in Z; point at the 3D midpoint
SELECT ST_3DInterpolatePoint(
'LINESTRING ZM (0 0 0 0, 10 0 10 20)',
'POINT Z (5 0 5)');
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10
-- Vertical line (zero XY extent); 3D projection works where 2D would not
SELECT ST_3DInterpolatePoint(
'LINESTRING ZM (0 0 0 0, 0 0 10 100)',
'POINT Z (5 5 5)');
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50