Move surface to lowest point of topography

AB01 · January 20, 2019, 9:08am

Hi,

How would I get dynamo to move square/rectangle shape surface to move to lowest point of topography?
Currently my graph creates array of points but is not accurate because the points may not be over the lowest part of topo. To get better accuracy means to create more points which will slow script down.

Aim is to get current revit family level and change parameter so it moves to lowest part of topography.

Anyone have better idea?

Also is it possible to keep the “Empty List” values after flattening? This is so each z value matches up, and empty list wont calculate which is what I want, provided this method is still required.

kennyb6 · January 20, 2019, 9:36am

If all you need is the lowest Z value, you can take the bounding box and then take the minimum point.

AB01 · January 20, 2019, 3:45pm

this is what I want to achieve:

JacobSmall · January 20, 2019, 11:33pm

Create surface as you have
Get bounding box from topo element
Get min point with a BoundingBox.MinPoint node
Get Z value using a Point.Z node
Get a point from your surface, and pull the Z value.
Subtract the the two Z values, get the absolute value, and multiply the result by -1.
Use a Geometry.TranslateByDirectionDistance to move your original surface along the Z axis (Vector.ZAxis node) by the negative distance found in step 6.

AB01 · January 21, 2019, 3:44am

Thanks everyone.
But I have several surfaces so what I really want is min Z-point of topo at each of these areas.
Is there a way to create topo bounding box the same x,y size of surface so it can work out the local min point?

kennyb6 · January 21, 2019, 3:50am

Does Surface.ProjectInputOnto work with a surface as the input? If it does, you could project the surface onto the topo, then take the new surface and find the bounding box/minimum z point.

AB01 · January 21, 2019, 3:57am

Couldn’t get it to work when i wire like this;

kennyb6 · January 21, 2019, 4:06am

What version of Dynamo are you using, 1.3?

Also you are inputing a point for the surface input, you should be using surfaces for both inputs.

Can you please show the full graph with outputs displayed? It is hard to see what you are doing.

JacobSmall · January 21, 2019, 4:12am

You’re feeding a point into the surface input.

AB01 · January 21, 2019, 4:17am

Yes, thanks for picking that up. But feeding surface result with empty list.
Dynamo 1.3.3.4111 to be exact.

kennyb6 · January 21, 2019, 4:20am

Likely you have the wrong order for the surface inputs. The topo should be the surface input, the surfaces you want to move should be the inputs to project. And can you reupload the pictures with the outputs displayed? Just seeing the nodes doesn’t show us what the process is.

AB01 · January 21, 2019, 4:26am

Ive fixed the inputs (still empty list) and shown the outputs.