19 Dec 2023

Exploring the possibilities of the Forma Extensions API

Instant Sun extension

The Autodesk team continues to be all in on building an open ecosystem for Forma developers. We have spent the last year building up capabilities, opening APIs and making it possible for everyone to build their own extensions on top of Forma, for whatever use case you can think of.

We’ve come pretty far, and we are continuing on. A few weeks ago, we hosted an "Extendathon" across the Forma team to put our Extensions APIs to the test. It resulted in a total of 10 extensions of varying degrees of polish, ranging from a multiplayer presenter mode over WebRTC, to visualizations of estimated site values based on an external database. 

We wanted to share four of these extensions that we think showcase the best of what is currently possible for developers to build on the Forma SDK. Most of these are open source and all can be tested out in Forma, or forked as a starting point for your own extension. 

But more importantly, we want to inspire and invite you to build your own extensions on Forma at our upcoming Extendathon at our Autodesk office in Oslo, Norway, from February 13-14. You can sign up to join the Extendathon waitlist below. 

Join the waitlist



Have you ever seen a park, a road, or a path that is so winding and inefficient to walk on that people have started to create their own shortcut paths? You don’t want your project to be full of those, do you? Enter Pathmaker: The one-stop solution to predict pedestrian pathways based on residential locations and popular destinations.

We deployed ant-like simulation to create paths on the map in Forma. We add points that are sources of new ants like houses, transportation hubs, tram stops, and points of interest like shops, churches and parks.

One challenge of this approach is the missing data of various unwalkable parts. This caused the ants to walk on water and jump off cliffs. But inside an urban area without these conditions, the simulation performed well.

You can find the sample on github here: https://github.com/spacemakerai/extendathon-pathmaker 


Instant Sun

We believe in outcome-driven design, and there is no better way to encourage this way of designing than the millisecond feedback loop of real time analyses. With this extension you can place volumes around your site and instantly see the effect on complex sun light scenarios. 

Here you see a real time analysis that runs on the GPU on your machine to calculate the sun conditions for each 15 minutes of the selected time interval.

It is exciting to see how easily we could build a real-time analysis using the GPU. This paves the way for more advanced GPU based analyses running interactively in the future. 



Terrain editing capabilities beyond flattening a specific area is a widely requested feature in Forma. Our industry expert Daniel Gameiro pointed out that building pads are never completely flat - there is always a need to create a slight slope so that, for example, surface water will be transported away from the site in the case of heavy rains.

We created the Terrainosaurus Rex extension to let users draw a polygon on the ground and replace the terrain within it by an arbitrary sloped plane. Since hackathons are also an opportunity to learn new technologies and have fun, we added a separate fun mode with animated waves moving across the terrain triangulation in the 3D scene while editing.

This is a good starting point for how to do granular editing of specific elements as an extension to Forma. This is close to the vision of the Industry Cloud, where the best tool is easily available without moving the user out of the context. 

You can find the sample on Github here: https://github.com/trygve-aaberge-adsk/extendathon-terrain-editing


Parking demand calculator

Parking demand is the number of parking spaces required for the apartments you build in a project. Calculating parking demand is one of those boring tasks that is unfortunately quite easy to get wrong. With the parking demand extension, you just leave this part to your computer. 

This parking extension lets you specify requirements for parking for each kind of building function. The calculator will calculate the current number of parking spaces in the project and show you how this compares to the required number of parking spaces based on your design.

This lets you focus on designing while staying in total control of the parking to building ratio on your site.

You can find the sample on Github here: https://github.com/fredrik-morken/forma-extension-parking-demand-calculator


Join the Extendathon!

As you can see, there is a lot of room for experiments and different capabilities that you can build on Forma. We see extensions as a way to tailor your own tools to fit your exact, custom business needs. We see opportunities for developers to build extensions as a service and a revenue stream, and we just know that more important than anything else; we must open our ecosystem to you, to make the tools we use to design our future cities optimal for architects, planners and engineers. 

Inspired yet? Join us to build extensions on Forma in Oslo, on the 13-14th of February 2024. Sign up to join the waitlist now! 

Join the waitlist


If flying out to Oslo isn’t quite in the cards for you yet, there will be plenty of other opportunities in the near future! Sign up for the Autodesk Developer Newsletter for the latest news on upcoming 2024 events like Accelerators, Bootcamps, and more. In the meantime, check out these Forma resources to get started on your own:

Documentation: https://aps.autodesk.com/en/docs/forma/v1/
Forma SDK: https://app.autodeskforma.com/forma-embedded-view-sdk/docs/index.html

Happy Holidays!


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