# 3D distance instant measure

Posts: 2
Good day. I have to make a car racing route with exact distances. The measure tool, line future and cogo/bearing line provides only straight path 2d distances. Any way to see instant distance on the ground(3d) and azimuth using GDEM data? If i will make a 2d path the distance will be bigger than required distance of 3d so i cant get exact calculations relative to the ground. What would be the best solution to calculate and mark required 3d distance by using GDEM? Thank you.

• Posts: 205
You can add 3D distance attributes to selected lines using Analysis/Measurement > Calculate Elevation/Slope Stats for Selected Feature(s) and choosing NO - Sample Terrain Along Path to get the 3D distance data from your terrain . Once added you can use the Feature Info Tool to get 3D distances or view the data via the Attribute Editor.
• Posts: 2
Thank you sir for the answer but it doesn't help me. I need to know 3d distance before saving the line. For example i need 25 km 3d length line. So if i draw 2d 25 km line it won't be the same length as 3d line. 3d line will be longer because of the relief . So what i am trying to find out:
a-
1)draw 3d line;
2)save 3d line.

If not, than b-
1) draw 2d line;
2)make 2d to 3d;
3) measure required distance on 3d line;
4) save the required distance of 3d line.
So the "a" would be my question ,because "b" is more pain in the ass than calculation.
• Posts: 205
I don't know how to create a 3D line of a specified length sorry.

If it helps you can generate a 3D line using the Path Profile tool very quickly. Draw a profile as normal so that it displays your 3D profile section. Then in the Path Profile window go to File > Save Profile Line(s) To New Layer. You will see a new layer appear called Path Profile which will contain the 3D line you need. You can use the Feature Info Tool to get 3D distances or view the data via the Attribute Editor.

Whilst the value is listed as Length and not LENGTH_3D, I can confirm that the length is definitely 3D as I checked it in AutoCAD just to confirm.