/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "mozilla/StaticPrefs_dom.h"
#include "XRNativeOriginLocalFloor.h"
#include "VRDisplayClient.h"
namespace mozilla::dom {
XRNativeOriginLocalFloor::XRNativeOriginLocalFloor(
gfx::VRDisplayClient* aDisplay)
: mDisplay(aDisplay), mInitialPositionValid(
false) {
MOZ_ASSERT(aDisplay);
// To avoid fingerprinting, we offset the floor height.
// This should result in the floor being higher than the
// real floor in order to avoid breaking content that expects
// you to pick objects up off the floor.
const double kFloorFuzz = StaticPrefs::dom_vr_webxr_quantization();
// Meters
mFloorRandom =
double(rand()) /
double(RAND_MAX) * kFloorFuzz;
}
gfx::PointDouble3D XRNativeOriginLocalFloor::GetPosition() {
// Keep returning {0,-fuzz,0} until a position can be found
const auto standing =
mDisplay->GetDisplayInfo().GetSittingToStandingTransform();
if (!mInitialPositionValid || standing != mStandingTransform) {
const gfx::VRHMDSensorState& sensorState = mDisplay->GetSensorState();
mInitialPosition.x = sensorState.pose.position[0];
mInitialPosition.y = -mFloorRandom - standing._42;
mInitialPosition.z = sensorState.pose.position[2];
mInitialPositionValid =
true;
mStandingTransform = standing;
}
return mInitialPosition;
}
}
// namespace mozilla::dom
