Procedural City Generator for Houdini | by MrShark

What is it?

An HDA for Houdini that can procedurally generate a City / Island of your choice based on Images or your own input!
This was originally developed as part of my studies, but after lots of requests I've remade it officially as a product so that you can put it into use of your own! I'm releasing this as an Alpha release of the HDA as there are some minor geometries that could use some tweaking and with your feedback and help, develop this further into an all around final City Generator.

Who is this for?

For people who are looking to create their own unique shapes of islands rather than using satellite data etc. it's just my own take at creating a City map and buildings that I've optimized as much for your use. Potential use cases for this system are:

• Create Custom aerial / establishing shots.
• Background fill, map creation.
• Use as a base geo for creating your entire city and enhance close up areas to fit your scene.
• Create high quality city using the base Map generator and populating it with your own high quality buildings.
• Also for people to maybe take apart and learn! There are a lot of unique systems and approaches I have taken to fix problems that arise with building this system, you should be able to go in and look around / edit the HDA to your liking.

What's inside?

I've provided 3 Folders inside of the .RAR file.

• "HDA" Includes all the HDAs that you might be looking for, the main one is used to generate the layout and base geometry from which you can take an either instance your own cities, or generate your own buildings from the primitives. If however you would like a final result, I've included 5 other HDAs to be able to generate Skyscrapers, Tall residential, Residential, Housing and Trees for as little processing power as possible.
• The "Starting HIP" folder is there so you can have an idea of how I have used the system to generate a city.
• The third folder is the "TEXTURES" folder, it includes test island images in case you want to test it out, as well as 32 UDIM building facades that you can apply to the buildings to easily get some textures onto the buildings.

Primary City map generator HDA, Provides you with 3 Inputs, and 9 Outputs as follows:

City Map Generator Outputs, example

Inputs:

• Custom Island shapes
• Highway curves input
• Custom Hotspots input
• Terrain geo input (For providing your own heightfield / displacement maps)

Outputs:

• Island GEO (Just the base ground layer)
• Highways GEO
• Roads GEO
• Farmland Map - You can scatter your own geometry onto this like Warehouses, Wind turbines, Electrical posts etc.
• Skyscraper Map - You can either connect the Skyscraper Generator HDA provided to generate up to 7 Versions of buildings from the map or use it to instance buildings based off of the Area of each primitive.
• Tall Residential Map - You can either connect the Tall Residential Generator HDA provided to generate variable building shapes utilizing UDIMs to add textures to each building from up to 32 Building Facades or scatter houses based off of each primitive.
• Residential Map - Same as Tall Residential but with shorter buildings.
• Housing Map - You can either connect the Housing Generator HDA provided to generator to generate variable housing and yard shapes or scatter houses based off of each primitive.
• Tree Points - This output provides the points to which you can either instance your own trees or connect the Tree Generator HDA provided to let it instance very optimized versions of trees.

All the HDAs connected to their hierarchy.

All nodes connected together Output

Additional Info:

• By purchasing a copy of this system, any updates in the future will be available on this same page.
• The version of Houdini I used to make the HDA is 20.0, I believe it should work in 19.5 as well but just be cautious and let me know if you have any troubles with the system!
• This is my first time creating and HDA for Houdini as well, I've got lots to learn so would love your feedback and ideas to be able to improve this system!
• The cover Photo has been composited In After Effects and Photoshop, there are some minor elements of AI that I used on the Ocean but the city itself has been left untouched from AI.