Fix 6DoF controllers rotation in WebXR

For the Quest2 devices, controllers used to show some abnormal rotation
to the top inside WebXR sessions. The problem was that we were applying
a 45º rotation to the controller transform instead of to the immersive
beam transform.

app/src/oculusvr/cpp/DeviceDelegateOculusVR.cpp

@@ -402,7 +402,11 @@ struct DeviceDelegateOculusVR::State {
 
  float offsetX = controllerState.hand == ElbowModel::HandEnum::Left ? 0.011f : -0.011f;
  const vrb::Matrix trans = vrb::Matrix::Position(vrb::Vector(offsetX, 0.025f, 0.05f));
- controller->SetImmersiveBeamTransform(controllerState.index, trans);
+
+ // Apply a 45º rotation to controller in immersive mode.
+ vrb::Matrix transform = vrb::Matrix::Rotation(vrb::Vector(1.0f, 0.0f, 0.0f), M_PI_4);
+ transform = transform.PostMultiply(trans);
+ controller->SetImmersiveBeamTransform(controllerState.index, transform);
  } else {
  // Oculus Go only has one kind of controller model.
  controller->CreateController(controllerState.index, 0, "Oculus Go Controller");
@@ -474,16 +478,10 @@ struct DeviceDelegateOculusVR::State {
  controller->SetCapabilityFlags(controllerState.index, flags);
  if (renderMode == device::RenderMode::Immersive) {
  static vrb::Matrix transform(vrb::Matrix::Identity());
- if (transform.IsIdentity()) {
- if (controllerState.Is6DOF()) {
- transform = vrb::Matrix::Rotation(vrb::Vector(1.0f, 0.0f, 0.0f), 0.77f);
- const vrb::Matrix trans = vrb::Matrix::Position(vrb::Vector(0.0f, 0.0f, 0.025f));
- transform = transform.PostMultiply(trans);
- } else {
- transform = vrb::Matrix::Rotation(vrb::Vector(1.0f, 0.0f, 0.0f), 0.60f);
- }
+ if (transform.IsIdentity() && !controllerState.Is6DOF()) {
+ transform = vrb::Matrix::Rotation(vrb::Vector(1.0f, 0.0f, 0.0f), 0.60f);
+ controllerState.transform = controllerState.transform.PostMultiply(transform);
  }
- controllerState.transform = controllerState.transform.PostMultiply(transform);
  }
  controller->SetTransform(controllerState.index, controllerState.transform);