Global Mapper v25.0

Tins and Such

Unknown
edited October 2007 in Elevation Data
The global mapper grid format seems to set the majority of the elevations to the nearest foot. I can see how this would help make for the much smaller file sizes and faster loading but it's just too coarse for the elevations for what we need. Is there any way to control the vertical resolution and set it to something a bit more accurate?

On import of an xyz point file as an elevation grid there is no option to set the grid spacing. I tried the lidar las format for the point files and this seems a bit more efficient than xyz but has the same problem and seems to have a tighter distance control setting. If the points are imported, then the elevation created, the grid spacing and distance can be set, but there's no script command I can find to do that.

Are there any elevation formats available which are actual TIN's as opposed to a Grid? If so, do you know which is the most efficient for storage and use?

Can an ESRI tin data set be loaded and if so, which format is it in the "open" dialog?

I'd prefer not to loose resolution in the data if possible but using the xyz's every time doesn't seem very practical.

Comments

  • global_mapper
    global_mapper Administrator
    edited September 2007
    The Global Mapper Grid format does store the elevation as integer values of whatever units are selected. If you need more than foot resolution, use the deci-feet unit option, then you'll get 10ths of a foot resolution (and a slightly larger file).

    If you want to manually set the grid spacing when gridding point data, first load the data as "Point Only" data. Then open the Overlay Control Center, right-click on the layer, then select the option to generate an elevation grid from the data. On the dialog that appears you will have the option to manually specify the grid spacing to use rather than accept the default.

    Global Mapper does not currently support using any TIN formats directly.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com
  • STH
    STH Global Mapper User Trusted User
    edited October 2007
    Global Mapper does not currently support using any TIN formats directly.
    Is this something that will be supported in the near future? For instance dtm or ttn files?
  • global_mapper
    global_mapper Administrator
    edited October 2007
    That is correct, Global Mapper does not currently support loading any TIN formats. The latest build of Global Mapper can generate a TIN in addition to an elevation grid when triangulating and gridding loaded data. The TIN is just generated as a series of triangular area features which can then be used like any other area features.

    Let me know if I can be of further assistance.

    Thanks,

    Mike
    Global Mapper Support
    support@globalmapper.com