Display Z-Features without 3d-Surface

[FriederDaeublin]

Hello,

I have a kind of comprehension problem in the 3D scene-function of ArcGISPro (3.5). For 20 years I have only worked in ArcMAp and ArcScene - now I am changing into AGP since over a year and am missing or misunderstanding a few functions in AGP.
The following: I created a 3D line (Z-feature) that was always immediately displayed in 3D in ArcScene. I could rotate and pan these Z-line features and view them from all sides. In AGP, although this feature has Z values, I always have to place it on a 3D surface - but I don't even have this surface yet. On the contrary - the Z-line feature is part of the surface I want to create. To control the Z feature, I would like to view it in 3D - but that is not possible. Is this a fundamentally different function in AGP compared to ArcScene? Am I doing something wrong?
Thx
Frieder

Translated with DeepL.com (free version)

[AyanPalit]

@FriederDaeublin Have you tried visualizing your 3D line in ArcGIS Pro local scene ? 

[FriederDaeublin]

@AyanPalit, 

of course i did. but it ist not shown in 3D until i define the elevation-source in the properties-dialog. The feature is 3D for sure - i can create a TIN with it. But i dont want it to be draped over a TIN. 
By the way. TINs are showing the same behaviour. In ArcMAP/ArcScene i can load any TIN on its own and it is shown in 3D. Here in "AGP Local Scene" I always have to set an elevation surface first - although the TIN (and the Z-Features) are carrying the Elevation by themselves.
This seems a kind of akward to me - thats the reaseon for thinking that I am doing something wrong basically. 
Why so I have to define a Elevation Surface (which a TIN definitely is) for a TIN or 3D-Feature?

In the screenshot you can see the Layer "Abfahrt_sections1_z" which is the 3D Layer I am talking about. An this Feature should by lying inside the TIN geometry by itself. But it is lying flat on the "ground" which means null elevation!

Do I have to specify somewhere the the feature itself has z-values which should be used for visualization?

[AyanPalit]

@FriederDaeublin Try moving the Layer "Abfahrt_sections1_z" under 2d Layers.

Also select the appropriate option at Layer Properties > Elevation > "Relative/On the ground". Try different options here.

[FriederDaeublin]

Sorry - you get me wrong. Thats exactly what I am talking about. 
the "Abfahrt_sections1_z" is a 3D-layer. And it is nor terferring to the Grund-Elevation. It has its own.

For better understanding: 

The Ground Elevation TIN is a Quarry and the Z-Line Feature "Abfahrt_sections1_z" is a constructed road down to the bottom of the quarry. I cannot refer the elevation of the road to the surface of the quarry.

In ArcScene both features - the TIN and the z-Line - are beeing displayed in their right 3-dimensional postition - without referring them to some ground elevation (see screenshot)

[FriederDaeublin]

Hey Ayan,
trying to move the "Abfahrt_sections1_z" Layer to "2d-Layers" does not change anything - BUT:
Moving it back to "3d-Layers" will show the Z-feature wit its origin z-values - hobering above my TIN - like it does in ArcScene. 
But this seems to be a workaround. I do not understand why it behaves like it does.