Elevation splines work great

[ADallas]

I ran into some weird problems a week ago, and with help from experts here, I figured out my problem: Importing DWG elevation data is hit or miss--if it wasn't set up for a logical terrain perimeter, or some elements of the terrain elevation layer are 0, it will totally mess up the Terrain Build in Chief.

 

Import survey data to a neutral layer (that is, don't map to elevation data), or just import a PDF file for tracing. Experts warn against using elevation points, and the tutorial videos make elevation lines seem like the obvious choice for creating fairly simple slopes. In my case, I modeled an entire neighborhood by tracing ~40 contour lines. Chief warned that building terrain with 2000+ interpolation points in non-Linear mode might take too long, but it finished in a few minutes.

 

Avoid these pitfalls:

 

• Make sure the elevation splines start and end outside the Terrain Perimeter
• Don't let contour lines cross (thanks, @glennw!)
• Make sure that each elevation spline is continuous--I kept missing by a few pixels when I zoomed in, meaning that most of the spline was at the elevation I set and part of it was at 0. Move the ends near each other and Chief makes it just one spline.
• Double-check each spline's elevation--if just one is 0, your terrain will be messed up. Good news, though--fix it, re-build, and you're good

 

My smaller tests were successful, so I went for the whole 11-acre neighborhood--27 lots. My Terrain Perimeter is 892' x 550'.

 

Note: I didn't have to trace anywhere near the number of contour lines you see. I traced a plan with a 5' interval, and Chief interpolated to a 2' interval. Actually, I skipped some contours that added no value, but of course, Chief didn't.

 

Thanks to @glennw, @Renerabbitt, @Kbird1, @Chopsaw and--from a 15-month-old post-- @DavidJPotter

[mtldesigns]

Looks great!

[Kbird1]

Yep looks good , and appreciate the Call-out Alastair ..... Thx.

 

Now for the 27 House Symbols to sit on it  

 

https://www.chiefarchitect.com/support/article/KB-00344/modeling-a-subdivision-or-lot-with-multiple-structures.html

 

Mick.