.bt terrains

It would be nice if World Machine had a check box when exporting .bt files that allowed the info at byte offset 60 ((2 (short) External projection))to be set either as 0: Projection is fully described by this header, or better for those of us using WM as part of the ME-DEM Project, set it to
1: Projection is specified in a external .prj file, then the prj file from the GM .bt tile or a leveller modified .bt tile could be used to automatically geo ref the eroded tile. (Leveller will allow you to select a different file to set the geo-ref, so you don’t have to manually do it )
Another wish, which I don’t even know if it is possible, as I don’t know much about wm’s heightfield mapping,besides basically it is 0 to 1,is two boxes at .bt export which allow the input of min and max elevations, but I guess then wm would have to recompute the heightfield from the min and add or subtract each elevation from that before writing the file.
Ben Giscoe, of the VTP project has a pretty good explanation of his.bt format at
[url]http://www.vterrain.org/Implementation/Formats/BT.html
,this is for .bt 1.3, I am not sure which format wm is exporting (didn’t think to look before posting.)
Just the .prj file inclusion would help alot, as the file could be opened in leveller, with it’s x and y scaling intact, and the the z span could be modified in filter>span to the range needed. Span is easy, scaling the x and y correctly takes some math and a known distance in meters on the map to figure the ratio from. SeerBlue

Hi there,

this might be possible. Oshyan has been nagging me for ages to add some sort of georeferencing support into WM. Some sort of support for it will happen eventually, although almost all of my work right now is going into WM Pro so anything about this will happen after that.

Yeah more full-featured Georef support would be cool, although of course when dealing with “virtual” terrain it’s a bit of an odd concept. But what Seer suggests seems fairly simple and would really do most of what we need on its own. I hope you can bump it up the priority list, say if there are any other updates to do to WM before Pro. :smiley:

  • Oshyan