topic Re: Generating different density road networks for subdivisions of a polygon extent in ArcGIS CityEngine Questions

Generating different density road networks for subdivisions of a polygon extent

MelanieVT — Mon, 13 Feb 2023 16:51:30 GMT

Hi all,

I have a land-use polygon file containing four different land-use types, as shown below.

land-use map

I have learned that I can introduce an obstacle map to exclude no-road network areas. So, no problem with the recreation polygon. However, I’m having trouble generating three different-density continuous road networks inside three residential areas. I mean, I can generate different-density road networks separately using different parameters. In this case, they are unconnected. So, is there a way to cope with this problem? For example, is it somehow possible to introduce the land-use file containing different segments (as in the case of the obstacle map), define separate parameters for each, and generate an integrated network with different densities?

Cheers,

Mel

Re: Generating different density road networks for subdivisions of a polygon extent

ThomasFuchs — Wed, 15 Feb 2023 10:01:37 GMT

Hello @MelanieVT
Thank you for the question. I suggest taking an iterative approach using multiple obstacle layers:
Obstacle layer—ArcGIS CityEngine Resources | Documentation.

Create an obstacle layer for the high-density residential area and grow a dense street network
Then grow a separate, more sparse network for the medium-density residential area as an obstacle.
Proceed with the low-density residential area accordingly
Now combine all three networks in a single layer and do a graph cleanup:
Cleanup streets—ArcGIS CityEngine Resources | Documentation
To ensure all parts are connected, grow the network together using the recreation area as an obstacle layer.
Finally, create a continuous road network by analyzing the graph and adjusting the street widths
Analyze graph—ArcGIS CityEngine Resources | Documentation

Re: Generating different density road networks for subdivisions of a polygon extent

MelanieVT — Wed, 15 Feb 2023 13:02:28 GMT

Hi @ThomasFuchs,

That is precisely what I was searching for, and it is a very clever approach indeed. I am very grateful for your response. Thank you so much🙏🏼

Best,

Mel