Problems of 3D building and making cross section

[daochan1]

Hi,

I just start learning 3D Analysist in ArcScene but got blocked by some problems:

I am working on a file in which there is a layer of topography (TIN )and a layer of buildings.

1. When I add the shapefile of buildings (the coordinates have Z values), they appear on the right location on the topography, however if I choose "floating on a custom surface" on the TIN layer in the layer properties, some of the building disappear. What is the reason?

2. I extruded the buildings with extrusion of layer properties. But most of the buildings are extruded as only walls but not solid blocks. How can I solve the problem?

3. How can I make a cross section from this 3D model? for example a section of a valley?

4. Is there any way to export TIN or buildings into Sketchup/AutoCAD/3D Max? I found only "export scene" from "file"

Thank you so much for answering these questions!

[KeaganAllan]

Hi,

I just start learning 3D Analysist in ArcScene but got blocked by some problems:

I am working on a file in which there is a layer of topography (TIN )and a layer of buildings.

1. When I add the shapefile of buildings (the coordinates have Z values), they appear on the right location on the topography, however if I choose "floating on a custom surface" on the TIN layer in the layer properties, some of the building disappear. What is the reason?

2. I extruded the buildings with extrusion of layer properties. But most of the buildings are extruded as only walls but not solid blocks. How can I solve the problem?

3. How can I make a cross section from this 3D model? for example a section of a valley?

4. Is there any way to export TIN or buildings into Sketchup/AutoCAD/3D Max? I found only "export scene" from "file"

Thank you so much for answering these questions!

Hi Dao,

I have been playing around with 3D Analyst a bit and may be able to at least be able to point you in a direction.
I am not saying my answers are correct and there will be people on this forum that will give you better answers, but I should hopefully be able to at least get you moving in a right direction.

1)  When you say the points have a (z) value, are they PointZ or Point? When they appear in ArcScene are they at the correct elevation? If a shp file has a Z value, you do not have to set the reference surface. I think you can even set the elevation to be read from a field in the attribute table.

2) When you say the buildings do not extrude as solid blocks, what do you mean? I think the type of shape you are using defines how the extrusion looks. A point may be a cylinder, a line a wall and a polygon a cube or cylinder. To add different shapes I think you have to edit it in external software (Sketch-up - see point 4).

3) To create a cross section, in the 3D Analyst tool bar, make sure your TIN is selected,  select interpolate line from the toolbar and then select "Profile Graph" its the second to last drop down menu in the toolbar. You can save or export this cross section.

4) there is a way to export the buildings to Sketch-up. I cant quite recall how it is done, but I think you create a "Multi-Patch" from the extruded buildings, then using the Conversion Toolbox you can export this Multi-Patch to Collada. Collada can be imported into Sketch-up.

I think something to always try and check (I have fallen prey to this many times) is to ensure you intial base data is projected correctly.

I hope I have at least pointed you in the right direction, as I said before I may be incorrect in my explanations (I am still learning myself), so try what I have said and hopefully you will come right.

Cheers
K