review vr stuff, fix controller-ui ray casting

android/quest/src/main/cpp/oculus_vr.cpp

@@ -22,7 +22,7 @@ struct QuestController : public VRController
     void update_state(double predictedDisplayTime, glm::vec3 head_pos)
     {
         vrapi_GetInputTrackingState(ovr_context, id, predictedDisplayTime, &tracking);
-        glm::vec3 c_pos = glm::make_vec3((float*)&tracking.HeadPose.Pose.Position) - head_pos;
+        glm::vec3 c_pos = glm::make_vec3((float*)&tracking.HeadPose.Pose.Position);
         auto c_rot_ovr = ovrMatrix4f_CreateFromQuaternion(&tracking.HeadPose.Pose.Orientation);
         auto c_rot_ovr_tp = ovrMatrix4f_Transpose(&c_rot_ovr);
         glm::mat4 c_rot = glm::make_mat4((float*)&c_rot_ovr_tp);