Placing two heightfields side by side

Started by MF_Erwan, November 21, 2009, 08:20:21 AM

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MF_Erwan

I want to make an image od the Gavarnie Circus, in the Pyrénées mountains (located between France and Spain). So I have downloaded the SRTM altimetric data from http://srtm.csi.cgiar.org/SELECTION/inputCoord.asp, opened them in 3DEM and exported as .ter files called Pyrenees E.ter (eastern part) and Pyrenees W.ter (western part). The width of the 2 files is 410 326 meters.
In Terragen 2 I loaded Pyrenees E.ter, put 0 as border blending, checked "Position centre" and put <205 163,0> as "Position" (205 163=410 326/2)
For Pyrennes W.ter I put <-205 163,0>.
The Gavarnie Circus is just near the limit of the 2 terrain, and when I rendered, here is what I obtained:


So what is my problem? Why isn't the limit between the heightfields good?

Erwan

Henry Blewer

A large number of Chinese workers came by and dug a foundation for a great wall. ???

It looks to me like the two height fields overlapped a little. Or there is an inconsistency in one of the height fields. You may have to use the programs GeoControl, or World Machine to get the data to join correctly. Then save the whole and import it into Terragen 2. Someone else may have an better idea.
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buzzzzz1

This might help with your issue?  BigBen shared this with us a while back----->> http://www.bigben.id.au/terragen/category/clip-files
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JimB

I had this exact same problem cobining DEM tiles in WorldMachine2. I assumed the lineups would be spot on when I typed in the offset values based on the tile sizes, but it ended up looking like what you have there. When I nudged them together they were a perfect fit. The data isn't always 100% accurate at the edges and can need a bit of loving care when combining.

Not saying it is the same, but you might try offsetting the tiles together until they join.
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