topic Re: Generate gray scale height map file from contour lines "level curves" in Autocad in AutoCAD Forum

Generate gray scale height map file from contour lines "level curves" in Autocad

powermetalroberto — Sun, 23 Jan 2022 06:10:30 GMT

Greetings, friends of the community, I ask for your help, I want to create a height map in PNG format in gray scales (I will leave a reference image attached) from a "level curves" file in Autocad, this is to import into Cities Skylines, a topography of the real world, I have tried several online tools that generate height maps, but they are too inaccurate or broken, so what I want is to create this height map on my own, I will use a contour file which is much more accurate, I really appreciate your help.

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

Pointdump — Sun, 23 Jan 2022 07:18:12 GMT

Hi Roberto,
You'll need Map 3D to do that. Vanilla AutoCAD can't do it.
Dave

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

powermetalroberto — Sun, 23 Jan 2022 07:29:29 GMT

Excuse my ignorance, I would like to know specifically how I have to do this, what programs I have to use, and failing that, what steps I have to follow, what I have is the contour file in CAD, thanks.

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

Pointdump — Sun, 23 Jan 2022 07:45:23 GMT

Hi Roberto,
You'll need Map 3D. Here's an excellent step-by-step from @ChicagoLooper:
https://knowledge.autodesk.com/support/autocad-map-3d/learn-explore/caas/screencast/Main/Details/3bd844ff-1510-45d5-9b2c-d9c0a4978107.html
Dave

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

j.palmeL29YX — Sun, 23 Jan 2022 10:08:47 GMT

Can you post an example of your source ("level curves") dwg-file please?

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

ChicagoLooper — Sun, 23 Jan 2022 13:36:46 GMT

@powermetalroberto wrote:
<<….this is to import into Cities Skylines, a topography of the real world….>>

It’s possible but you’ll need to provide more background.

What is Cities Skylines? Is it a geospatial program and does it understand coordinate geometry?

What format can Cities Skylines use for import purposes? Raster, such as DEM, Tiff? Or vector such as Dwg, Dxf, Shp?

Do you have topographic contours in Dwg format? Can you upload that file?

Can you upload some of your previous Cities Skylines’ maps so the forum can see the type of work you want to accomplish?

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

powermetalroberto — Thu, 17 Feb 2022 03:55:16 GMT

Hi dave, i only have 1 question, i could make the surface in the example in civil 3D, from my "level curves" from autocad? if this is posible how i could do it. i atach a file of these level curves for more context.

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

ChicagoLooper — Thu, 17 Feb 2022 04:40:06 GMT

To make a surface as shown below, you’ll need AutoCAD Civil 3D. Plain vanilla AutoCAD doesn’t have the capability to perform that operation.

Tin surface made in Civil 3D and displayed in the Object Viewer.

BTW, the elevations associated with your contours have negative values. Negative numbers typically refer to elevations ‘below mean sea level’ so the implication is your lines represent bathymetry and that means the surface is underwater. Is that your intention? You want to model the ocean floor?

Also, your x,y’s are very close to 0,0,0 and don’t look like they are referenced against a ‘known coordinate system.’ If that’s true, then Bing imagery, if turned on, cannot be used in a meaningful way.

Re: Generate gray scale height map file from contour lines "level curves" in Autocad

powermetalroberto — Thu, 17 Feb 2022 21:01:01 GMT

Thank you for answering, in effect, the level curves are not below sea level, they are in fact from an area with a mountain range in the former, the lowest part is a ravine with a small stream, I only put the level in that way because I usually use these lines in revit to generate terrains, since I am an architecture student and this is my drawing mechanism, and the "level 0" in the z axis I put there arbitrarily, in any case, these "curves of level" are a fraction of a larger mapping that I'm still working on, how does civil 3D work? Do I have to have these "level curves" georeferenced as well as in programs similar to Arcmap? If so, how do I do this? to later export it to civil 3D? my goal with all this is to have a height mapping like the image that I attached in the beginning, since I want to create a terrain as close to reality in the Cities Skylines program, which only accepts information in PNG of height maps by variation of colors from white to black, I appreciate your patience and help.