diff options
Diffstat (limited to 'components/script/dom')
| -rw-r--r-- | components/script/dom/xrsession.rs | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/components/script/dom/xrsession.rs b/components/script/dom/xrsession.rs index 60d93d4e5e0..3d4bbc7716b 100644 --- a/components/script/dom/xrsession.rs +++ b/components/script/dom/xrsession.rs @@ -285,6 +285,9 @@ impl XRSessionMethods for XRSession { /// https://immersive-web.github.io/webxr/#dom-xrsession-requestanimationframe fn RequestAnimationFrame(&self, callback: Rc<XRFrameRequestCallback>) -> i32 { + // We only need to send a message once, until a raf callback executes. + let should_send = self.raf_callback_list.borrow().is_empty(); + // queue up RAF callback, obtain ID let raf_id = self.next_raf_id.get(); self.next_raf_id.set(raf_id + 1); @@ -315,10 +318,21 @@ impl XRSessionMethods for XRSession { }), ); } - let sender = self.raf_sender.borrow().clone().unwrap(); - // request animation frame - self.session.borrow_mut().request_animation_frame(sender); + if should_send { + // If our callback list is empty, it either means this is the first request, + // or raf_callback executed, in which case we should + // send a message to request an animation frame. + // + // This prevents multiple messages being sent for a single call to raf_callback, + // and multiple message are unnecessary, + // since one call will already deal with multiple potentially enqueued callbacks. + // + // Allowing multiple messages could keep the main-thread, + // where the session thread might be running, looping on incoming messages. + let sender = self.raf_sender.borrow().clone().unwrap(); + self.session.borrow_mut().request_animation_frame(sender); + } raf_id } |