osm roads, and sat/mask/terrain tips

[vad 12]

Just a mini blog about ways I found around some problems I ran into.

 

Best heightmap from:

http://earthexplorer.usgs.gov/

Plug that into QGIS:

http://www.qgis.org

The problem here is if you choose a part of the earth different to 31N (which TB is all about) then your nice square street grids are going to be warped, but I found a convoluted way around it.

So make a nice square vector in qgis when youve got the right square street shapes for your location/CRS. Rip the raster heightmap and use that square shape as your template (also try to measure the area to be 20km across or whatever size your going for (20 has least probs).

Then plug that into L3DT (free), edit it a bit if you like, then spit out an xyz file for TB (xyz works better than png).

Sat image:(for USA)

http://viewer.nationalmap.gov/basic/

get all the smaller maps for your area, jp2 files, then stitch them together in geoviewer

https://www.lizardtech.com/geoviewer-pro/overview

then plug that into qgis for your sat image, set canvis crs in bottom right to your square template and raster>extration>clipper same as heightmap

mask:

http://viewer.nationalmap.gov/basic/

there is a shape file called, :

National Land Cover Database (NLCD) Tiled Data Distribution SYstem (TDDS)

will give you a good detailed mask, put it in qgis and edit all the values to correspond to your config or vise vera, also can add to L3DT but it changes all you custom color values which is annoying

 

then in qgis you got your osm plugin, the pain here is the vector points get tied to the orginal gps and when you plug that into 31N its all skewed. what you want is a process called 'rubber sheeting' but the plugins seemed to be missing, I tried all the tricks with qgis but ended up with a small star shape in TB, anyway what you can do is clip the vector streets with your template square, then export it as a DFX file, (save the orginal .dbf file cause that gets screwed up and you can switch it out for the original), open the dfx in adobe illustrator (haven't tried equivalents) inside a already open 2048x2048 template (adjust accordingly) scale to page. Then export that back to DFX now its been wiped of gps data, and put it in qgis, set it's properties to 31N and it will remain square shaped. use affine transformation and scale x and y by 10 and easting to 200000. replace the .dbf file. ready for import to TB and it will match up exactly (hopefully)

 

I skiped all the other info found in tutorials and wont respond to questions, just thought I'd share the workarounds I found in case like me you googled and couldnt find, maybe it'll help someone.

[HorribleGoat 1473]

Would recommend .asc from L3DT. Its pretty much the same as .xyz but I've sometimes come across problems with xyz and Terrain Builder. Using .asc has never let me down.