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PostPosted: 10 Oct 2017 03:27 
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Joined: 16 Mar 2015 02:28
Posts: 3
Location: Ohio, USA
I run into this whenever I mess around with imported route data from third party resources like government route data. And I know the solution is typically to redraw the routes with simple lines, but that's very tedious work. I would really love to see some kind of feature to "auto simplify" route data to a point where map tiles can be imported without redrawing my routes. That, or maybe an update so it can just figure out the map tiles no matter how complex the route data.

That would be my #1 top request as I run into it every time I start a new route area.


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PostPosted: 10 Oct 2017 15:12 
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Joined: 05 Jan 2011 16:45
Posts: 1055
"Auto simplify" sounds easy but requires rather complicated algorithms. You are aware of the command to draw a new and independent route on top of the complex one? Main menu: Route | Simple Route Editor, New Route (Ctrl+Shift+E)


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PostPosted: 13 Oct 2017 13:05 
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Joined: 14 Sep 2017 00:43
Posts: 16
To get around this myself, I have just saved my routes into ESRI shape file.
Then I used the program OPENJUMP to edit the shape file

Once you open your route in open jump right click it and select editable.
Then in the menu choose "sextante"-->"sextante toolbox"

You can try a few different tools found under "Tools for line layers"

Two tools you will find useful are join adjacent lines and simplify lines.
In both tools use values of 0.01 to begin and look how it modifies your route.
Another useful tool is done by, selecting your entire route in openjump, click in the main window and press CTRL-A
then choose TOOLS ---> analysis ---> buffer
Then set for the fixed distance of 0.01 and number of segments per circle quarter to 2 or 3

You can try multiple ring buffer to get lines that surround your routes in equal spacing.
You an then save the layer you want in the same shapefile format and open it in transdem and use it to do the geomapping.

This could be solved if there was a way to import LARGE (2 gig and larger) georeferenced raster maps into transdem, because there are many programs out there that can make a georeferenced .geotiff, but transdem cannot open a VERY LARGE georeferenced .geotiff, it can only open a 32mpixel georeferenced raster.

You can make your own 32mpixel georeferenced raster outside of transdem using the program called sas. but like i said you are limited to importing rasters that are very small.


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PostPosted: 16 Oct 2017 00:49 
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Joined: 16 Mar 2015 02:28
Posts: 3
Location: Ohio, USA
I don't doubt the math is difficult. I'm sure it's a difficult prospect. I'm just wishing there were a simpler way. For example, the one I'm working on right now, I've gone through and drawn far simpler lines and my route file went from the imported 2MB STR file to just 118kb, and it's still telling me it's too complex to run the map imports, so I'm going through it again. It's just a very tedious process. I will give the suggested OPENJUMP process a try though.


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