World/Udon Bugs & Feature Requests

If U# scripts with BehaviorSyncMode.Manual (or Continuous) and None set exist in the same object, an error will occur as shown in the attached image. (When SC2 Input Manager is None and SC2 Seat Adjuster is Manual) When combining Manual (or Continuous) and None, it would be nice if U# scripts behaved as synchronization objects without displaying any error-like messages. In fact, this combination works as Manual Sync. Looking at the archive logs below, it seems that this implementation is already in place, and the error message is just being displayed extra. https://feedback.vrchat.com/udon/p/syncmode-none-should-be-weaker-than-other-sync-modes

If an avatar of a remote user is muted by calling VRCPlayerApi.SetAvatarAudioFarRadius(0) during OnPlayerJoined(), you cannot restore that avatar audio later by calling VRCPlayerApi.SetAvatarAudioFarRadius(40) under certain conditions. The avatar audio stays muted for you. The remote user can even disable and enable the audio toggle again, but it will still not be audible to you. Contrary to that, if the user joins and you don't call .SetAvatarAudioFarRadius(0) during OnPlayerJoined(), you can always toggle their audio on and off later without any issues. The issue also depends on the avatar setup: if the avatar audio is manually toggled via an animation after joining the world (e.g. a VRCFury toggle), the audio will never play, even if that animation is toggled again after unmuting the avatar. if the avatar audio is always-on, the audio behaves as expected, there is no issue. Avatars for testing: (VRCFury toggle) -> Bug happens https://vrchat.com/home/avatar/avtr_8897aa55-4877-4aac-bac2-1e3280e950f4 (OnLoad audio) -> Works fine https://vrchat.com/home/avatar/avtr_e77f5414-63b3-4d1b-aa7a-4b25cd299d48 World for testing: https://vrchat.com/home/world/wrld_717f7988-3503-4616-90b5-9d492d043b87/info Attached is the only script that is in the world and a screenshot of the decompiled VRCFury toggle. How to replicate: Join the world https://vrchat.com/home/world/wrld_717f7988-3503-4616-90b5-9d492d043b87/info Let a remote user with that avatar join ( https://vrchat.com/home/avatar/avtr_8897aa55-4877-4aac-bac2-1e3280e950f4 ) Let that user toggle their avatar audio on (via the expression menu) confirm that you can toggle their audio on/off with the button in the world toggle their avatar audio off with the button in the world let them rejoin let them toggle their avatar audio on (via the expression menu) confirm that you cannot hear their audio if you click the button in the world confirm that you cannot hear their audio, even if they toggle it off and on again (via the expression menu)

Since bone transforms aren't exposed, we can't parent objects to players and need to use expensive and complicated update loops for such a basic task, which also results in ugly/janky object movements and low performance. Please give us a simple function like .SetParent(Transform t, Boolean b) for .GetTrackingData(VRCPlayerApi.TrackingDataType.x) and .GetBonePosition(HumanBodyBones.x) and for VRCPlayerApi.GetPosition

## Problem Media files can contain multiple audio tracks (for example Spanish, English and Japanese), but worlds using VRCAVProVideoPlayer cannot enumerate or select those tracks from Udon. The player chooses one track and world authors have no supported way to change it. This prevents proper multilingual cinema, anime, karaoke, event and accessibility experiences. Current workarounds require duplicating the full video, transcoding variants on a server, or running a second audio player and fighting synchronization. AVPro itself has audio-track APIs, but the VRChat wrapper does not expose equivalent functionality to Udon: https://www.renderheads.com/content/docs/AVProVideo-v3/api/RenderHeads.Media.AVProVideo.VideoPlayer_AVPro.html VRChat video-player documentation: https://creators.vrchat.com/worlds/udon/video-players/ ## Requested API Please expose a small, local API on VRCAVProVideoPlayer, with names similar to: int GetAudioTrackCount() string GetAudioTrackLanguage(int trackIndex) string GetAudioTrackName(int trackIndex) int GetSelectedAudioTrack() bool SetAudioTrack(int trackIndex) An event indicating that track metadata is available would also be useful. The exact API names are not important. The important requirements are that Udon can enumerate the available tracks, show their language/name, and select one. ## Behaviour Audio-track selection should be local by default, so different users in the same instance can listen to different languages while watching the same synchronized video. Changing track should not change the shared URL, playback state or time for other users. Switching during playback should preserve the current playback position. If the backend must pause or reopen the media, the SDK could handle that internally or document the required sequence. A capability check is acceptable when a platform or media backend does not support track switching. PC-only support initially would still be useful if cross-platform parity is not immediately possible. ## Acceptance example A world plays one media URL containing Spanish, English and Japanese audio tracks. Two users watch the same synchronized video at the same timestamp. User A selects Spanish locally. User B selects Japanese locally. The video remains synchronized and neither user's choice changes the other user's audio. This would enable true multilingual playback without storing or streaming duplicate copies of the video.

% operator (Remainder operator) is not exposed to Udon. This makes some operations impossible! I can't believe that this has been neglected since 2020. (I know https://feedback.vrchat.com/udon/p/long-remainder but it has been neglected since 2020 so I created new issue.)

With the implementation of the Trampolines I've noticed it seems to be the straw that broke the camel's back. Items are being disabled for worlds. Both paid and free assets are being disabled. I think classifying a item as small or large would allow for smaller props to stay while large ones like the pool, trees and trampolines can be toggled off.

At the moment Udon doesn't have this library exposed to Udon. Considering how easy is to tamper with String Loading (DNS poisoning and you are gucci), having this exposed to validate response signatures is required.

When pointing at a canvas, a little arrow appears. It would be nice if we could get the 2D coordinates of that arrow within the canvas, without having to worry about determining what input/raycast method generated it. In theory Unity has plenty of ways of doing this, but I don't know of any of them that are exposed to UdonBehaviour. (The closest that I've gotten is to cover the canvas in a giant slider, which at least gives you the X coordinate of any clicks on the canvas, but trying to add a second rotated slider to get the Y coordinate just covers up the X one...)

VRChat is working on an improvement to Udon, VRChat's scripting system. Currently, World creators can write code in two different ways: Udon Graph UdonSharp VRChat is introducing a third way: Soba Creators can write Soba scripts in C#, similar to UdonSharp. Soba scripts are compiled to Microsoft's Common Intermediate Language (CIL). This allows Soba to use a variety of features that are not available in the Udon Graph or UdonSharp.

Players and world creators would appreciate a new character controller for VRChat worlds. It should work mostly like VRChat's current character controller, but has a variety of improvements: Players can stand on moving platforms. Going upstairs and slopes is smoother. Players can get pushed around by the colliders. It's better at getting players unstuck from geometry. Udon has greater control over the character controller. ... And more!