235-port limit in User Actors and Macros — Isadora 4.5.1

[Cacoos]

Subject: 235-port limit in User Actors and Macros — Isadora 4.5.1 freezes when adding more

Hello Isadora Support Team,

I am experiencing an issue when adding a large number of User Input or User Output actors inside a User Actor or Macro in Isadora 4.5.1.

I can add up to 235 inputs or outputs, but attempting to add more causes Isadora to freeze. I did not encounter this limitation in the previous versions I used.

System configuration:

• Isadora 4.5.1
• MacBook Pro with M5 Max
• macOS Tahoe 26.5.2

Steps to reproduce:

1. Create a new, empty project.
2. Create a User Actor or Macro.
3. Add User Input or User Output actors inside it.
4. Attempt to exceed 235 ports — Isadora freezes.

The issue occurs even in an otherwise empty Macro, with no JavaScript actor, OSC processing, or other logic inside. This suggests that the problem is related to creating or managing the ports rather than processing incoming data.

My project requires 253 signal inputs plus one reset input, for a total of 254 inputs in a single User Actor or Macro.

Could you please clarify the following?

• Is the 235-port limit intentional, or is this a bug in version 4.5.1?
• If it is intentional, why was this limitation introduced, and can it be increased?
• Does the limit apply separately to inputs and outputs, or to their combined total?
• Is there a supported way to use 254 inputs in a single User Actor or Macro without freezing?

I can provide a minimal test project and a screen recording demonstrating the issue if needed.

Thank you for your assistance.

Best regards

[DusX]

@cacoos said:

My project requires 253 signal inputs plus one reset input, for a total of 254 inputs in a single User Actor or Macro.

 I would recommend bundling your similar parameters into JSON. I do this all the time for inputs/outputs. It can really make connecting things A LOT easier.

see: Using the JSON Parser and JSON Bundler Actors : TroikaTronix

[Woland]

@cacoos

1. JSON Bunder and JSON Parser actors can be used to reduce the number of inputs you need.
2. Depending on how many instances of the User Actor you need, you could also use Broadcaster/Listener and/or Set/Get Global Values actors to get some of the information into your User Actors

@Cacoos wrote:

 I did not encounter this limitation in the previous versions I used.

I just tried in Isadora 3.2.6 and saw that I can't add 256 inputs there either. What version are you referring to? (Just asking because if we can pinpoint the last version where it did work, we can see what changed about this in the next version.)