topic Re: Manually setting streetWidth for setback() in ArcGIS CityEngine Questions

Manually setting streetWidth for setback()

BrettAchorn — Mon, 19 Nov 2012 16:10:56 GMT

I'm working with an imported shape file that has lots, and I'm trying to use setback() with it. I've done some analysis and I've got a list of all the street facing edges for each lot, but there doesn't seem like a good way to feed that information back into the system (there doesn't seem to be a good way to set an array attribute like streetWidth).

Any thoughts on the right way to do this? There doesn't seem to be a clear way to "manually" do the operation myself (not all the lots are quads, so comp(e) with variable length indices doesn't seem possible)

Thanks,

Brett

Re: Manually setting streetWidth for setback()

MatthiasBuehler1 — Tue, 20 Nov 2012 09:48:49 GMT

Hi !

You'll have to set this array with Python, this can not be done with CGA.

Let me know if you have some experience with scripting (esp. Python), this will be fairly technical .. 🙂

Re: Manually setting streetWidth for setback()

BrettAchorn — Tue, 20 Nov 2012 15:05:19 GMT

I do a lot of python, so fire away. Thanks.

Re: Manually setting streetWidth for setback()

MatthiasBuehler1 — Wed, 21 Nov 2012 12:50:28 GMT

Ok. 🙂

This thread : http://forums.esri.com/CityEngine/forum-44564.html
page 2, my last post, script named 'setStreetEdges_v1.0.py'.

Check the end of the script, esp. short before :

ce.setAttribute(shape, objAttrName, streetWidthAttrValueList)

This will show you how to write that list.

One thing I've just noticed is that in this line :

streetWidthAttrValueList = highestEdgeIndex*[0]

-> My coworker made a similar script which states:

streetWidthAttrValueList = highestEdgeIndex*[None]

So it can be that then, the streetWidth() attributes with the value '0' do not appear in the Obj Attr list in the Inspector, which even may be better. Try playing with this.

Concerning the indexing :
Note that ArcGIS stores the vertex order clockwise, while CE interprets the vertex order counterclockwise, which messes up the order you have in ArcGIS. But you can fix this by a function which translates between the two worlds.

Let me know if some things are unclear !

Matt