Draping lines - add new verts automatically
mattpwalker
Global Mapper User
It would be good to have a modified drape / (apply elevations from terrain layers) that inserted verts at any intersection of the dropped spline and surface TIN edge.
This would enable a correctly draped line without a lot of unnecessary vertices (which is the current method given a resampling of the spline is required currently if you want to avoid the spline intersecting varying height terrain).
The following diagram crudely illustrates what I mean. My understanding is that currently when draping, for each vertex in the line, there is a height lookup from the underlying grid and the elevation is then applied to that vert (shown as blue dots in the diagram).
What I'd like to see is for each intersection of spline and edge of the underlying TIN, that there be a new vert inserted to the spline and this have a height also applied. This would yield a spline which actually conformed to the terrain accurately without needing to sub-sample with lots of redundant points.
AlternativeDrapingMethod.jpg
Many thanks
Matt
This would enable a correctly draped line without a lot of unnecessary vertices (which is the current method given a resampling of the spline is required currently if you want to avoid the spline intersecting varying height terrain).
The following diagram crudely illustrates what I mean. My understanding is that currently when draping, for each vertex in the line, there is a height lookup from the underlying grid and the elevation is then applied to that vert (shown as blue dots in the diagram).
What I'd like to see is for each intersection of spline and edge of the underlying TIN, that there be a new vert inserted to the spline and this have a height also applied. This would yield a spline which actually conformed to the terrain accurately without needing to sub-sample with lots of redundant points.
AlternativeDrapingMethod.jpg
Many thanks
Matt
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