MicroDem / HOG giving grid lines even though TGA has none..

[RPearson]

As it turns out, it was indeed the resolution that was causing the forest. The datasets I've been working with have all be 1 arc sec or more in resolution (less is better here), which translates over to about 30m. When trying to convert that native resolution over to a Targa file, HOG can't properly interpolate the data since its only capable of working with exactly 10m resolution, so it just fills in the missing data points with empty elevations, resulting in the forest. The actual tops of the pillars do conform to the DEM, but every space around each is at elevation 0. The problem was corrected in my case by forcing the output ASCII xyz file to 10m resolution, leaving me with a nice smoothly contoured layout, however, even a 20 mile section of track produced a 600mb xyz file at that resolution, leading me to believe that I'd be constrained to ~40mi at a time of route, a very small amount when thinking about rolling out 2,300 miles.

Because of this (TransDEM works a little better with memory and should be able to process closer to 100mi at a time), and because of the spline laying feature, I've decided to go ahead and order TransDEM. I'm hopeful that it will help me produce this mess a little faster and more smoothly, though time will tell.

Well I can't say exactly what you actually did to resolve your problem but the resolution shouldn't cause the problem you describe. I know because I used various resolutions in the past and you can see in the following screen shots that HOG can handle them correctly.

I used a DEM of Orbisonia Pa - one of about 12 I merged together to make the route I'm working on. I resampled it at 100m, 30m and the original 10m resolution in MicroDem. Saved as ASCII xyz dems and ran thru piglet and HOG. You can see in the following screeenshots that the terrain was created normally. You can see it uses a simple linear interpolation scheme to fill in the data it needs. This is very pronounced in the 100m resolution terrain. This is without telling HOG to interpolate the data. If you tell it to interploate it will smooth things out using higher order interpolation schemes.

100m resolution:

30m resolution:

10m resolution:

Roland - good to hear you're making progress. Trying to get info out of Auran on the map file fomats has been one of the bigger frustrations in my Trainz experience. I just wanted to get an updated version of what I had for TRS2006 but it seems thay were too busy and seems they've been too busy for many years now. I've hacked the formats with my hexeditor before. If I want to continue work on the track programs I guess I'll end up doing it again.

Bob Pearson

 

[SlickWilly]

How are you getting the TIGER data to overlay the DEM? The only explanation I have found says to click - Modify then All TIGER in MicroDEM, which does not exist. That tutorial is very old and I am using MicroDEM 10.0, build 2008.12.30.1 Even the MicroDEM help menu seems to be outdated.

Willy

 

[Dermmy]

- Modify then All TIGER in MicroDEM, which does not exist. Willy

You are right - it doesn't, I think you are trying to combine two separate steps.

The 'Modify' is Grid/Neither

All Tiger - is under Overlay

 

[SlickWilly]

Rather then hijack this thread I started a new one here
http://forums.auran.com/trainz/showthread.php?p=428906#post428906
Willy

 

[817TAYLOR]

So now I'm running into trouble again . Working with the trial, I exported the XYZ file and imported it into HOG. The resulting map was a "forest" of points, which didn't clear up even after I redid the ground file with "interpolation" selected. This is what it looked like:

*image romoved*

Going back into Global Mapper, I realized that the XYZ file was being outputted with a resolution of about 100m per point, which I think is just too much for HOG / Trainz to smooth. So I increased it to the 10m resolution that the SRTM is supposed to come in, and now the XYZ file is nearly 4GB and I can't get HOG to work with it... Where am I going wrong now?

man that pic looks like the glass forrest from the tv series Threshold
look that series up it is pritty twisted