Pipeline Type cannot be changed

[mjansen4857]

Describe the bug
When using the PhotonVision jar built from the main branch, the AprilTag pipeline seems to be unusable, and is forcibly changed to the ArUco pipeline. This happens both when starting from a fresh install (after deleting photon.sqlite) the default AprilTag pipeline selection is changed to ArUco, and manually changing it to AprilTag also just switches to ArUco.

This behavior is not present on 2025.3.1 and 2026.0.0-alpha-2

Logs:

photonvision-logs-3.zip

To Reproduce
Steps to reproduce the behavior:

1. Install Photon build from main
2. Activate camera
3. Notice current pipeline is ArUco
4. Select AprilTag pipeline manually
5. Current pipeline is still ArUco

Screenshots / Videos

Screen.Recording.2025-11-23.at.1.26.03.PM.mp4

Platform:

• Hardware Platform (ex. Raspberry Pi 4, Windows x64): Radxa CM5 (RK3588S)
  • How is it powered? (ex. Zinc-V, Pololu Buck Converter, Battery Bank): USB C Laptop Charger
• Network Configuration (Connection between the Radio and any devices in between, such as a Network Switch): Device -> Ethernet Switch -> Router
• PhotonVision Version: dev-v2026.0.0-alpha-2-25-g8edc79b8
• Browser (with Version) (Chrome, Edge, Firefox, etc.): Safari
• Camera(s) Used: USB OV2311 & OV9281

[mjansen4857]

Logs will be filled with camera errors, this is probably due to the scuffed carrier board I'm using and unrelated to this issue.

[mcm001]

Every pipeline creation print I can see indicates PipelineManager is trying to create an AprilTag pipeline

[2025-11-23 18:26:25] [VisionModule - PipelineManager] [DEBUG] Creating AprilTag pipeline
[2025-11-23 18:26:25] [VisionModule - VisionModule - Arducam_OV9281_USB_Camera] [INFO] Setting pipeline to 0
[2025-11-23 18:26:25] [VisionModule - VisionModule - Arducam_OV9281_USB_Camera] [INFO] Pipeline name: New Pipeline

which always happens here

photonvision/photon-core/src/main/java/org/photonvision/vision/processes/PipelineManager.java

Line 257 in 63593b8

currentUserPipeline =

[mcm001]

Because we see that print, I'm confused how we could be stuck in aruco. No way that we're always in apriltag, but the frontend has an off by one becaue of #2180 maybe?

[samfreund]

Because we see that print, I'm confused how we could be stuck in aruco. No way that we're always in apriltag, but the frontend has an off by one becaue of #2180 maybe?

In that case I would expect OD to break as well.

[Gold856]

It seems like pipeline types are just stuck in general. Creating a new pipeline and selecting AprilTag works, but attempting to switch the type fails.

[Gold856]

Actually, it's only sort of stuck. Attempting to switch to AprilTag, then attempting to switch to Colored Shape will get it to switch to AprilTag. I'm getting Not changing settings as AprilTag and AprilTag are identical! in the log when trying to switch from ArUco to AprilTag. (????)

[Gold856]

There appears to be some sort of off-by-one error. Attempting to switch from ArUco to Reflective will actually set the pipeline type to Colored Shape.

[Gold856]

The off-by-one-error is in the UI. I got a NoSuchFieldException thrown when attempting to change an ArUco pipeline (which is actually an AprilTag pipeline). Additionally, the pipeline dumped to the console is, in fact, an AprilTag pipeline.

[Gold856]

Found it. The root cause is here:

photonvision/photon-server/src/main/java/org/photonvision/server/DataSocketHandler.java

Line 158 in 63593b8

var type = PipelineType.values()[(Integer) arr.get(1) + 2];

When Focus Mode was added as a new pipeline type, this broke the mapping between the client's internal pipeline type numbers, and the server's pipeline type numbers. This now needs to be a + 3 to compensate. currentWebsocketPipelineType from CameraSettingsStore.ts likely also needs a similar update.