Source/WebCore/platform/vr/openvr/VRPlatformDisplayOpenVR.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2018 Igalia, S.L. All right reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  *
  */

 #include "config.h"
 #include "VRPlatformDisplayOpenVR.h"

 #if USE(OPENVR)

 #include <wtf/text/StringBuilder.h>

 namespace WebCore {

 uint32_t VRPlatformDisplayOpenVR::s_displayIdentifier = 0;

 VRPlatformDisplayOpenVR::VRPlatformDisplayOpenVR(vr::IVRSystem* system, vr::IVRChaperone* chaperone, vr::IVRCompositor* compositor)
     : m_system(system)
     , m_chaperone(chaperone)
     , m_compositor(compositor)
 {
     m_displayInfo.setDisplayIdentifier(++s_displayIdentifier);
     m_displayInfo.setIsConnected(m_system->IsTrackedDeviceConnected(vr::k_unTrackedDeviceIndex_Hmd));

     StringBuilder stringBuilder;
     stringBuilder.appendLiteral("OpenVR HMD");
     char HMDName[128];
     if (auto length = m_system->GetStringTrackedDeviceProperty(vr::k_unTrackedDeviceIndex_Hmd, vr::Prop_ManufacturerName_String, HMDName, 128)) {
         stringBuilder.append(" (");
         stringBuilder.append(HMDName, length);
         stringBuilder.append(')');
     }
     m_displayInfo.setDisplayName(stringBuilder.toString());
     m_displayInfo.setIsMounted(false);
     // FIXME: We're assuming an HTC Vive HMD here. Get this info from OpenVR?.
     m_displayInfo.setCapabilityFlags(VRDisplayCapabilityFlagNone | VRDisplayCapabilityFlagPosition | VRDisplayCapabilityFlagOrientation | VRDisplayCapabilityFlagExternalDisplay | VRDisplayCapabilityFlagPresent);

     m_compositor->SetTrackingSpace(vr::TrackingUniverseSeated);

     updateEyeParameters();
     updateStageParameters();
 }

 VRPlatformDisplayInfo::FieldOfView VRPlatformDisplayOpenVR::computeFieldOfView(vr::Hmd_Eye eye)
 {
     float left, right, top, bottom;
     // OpenVR returns the tangents of the half-angles from the center view axis.
     m_system->GetProjectionRaw(static_cast<vr::Hmd_Eye>(eye), &left, &right, &top, &bottom);
     return { -rad2deg(atanf(top)), rad2deg(atanf(bottom)), -rad2deg(atanf(left)), rad2deg(atanf(right)) };
 }

 void VRPlatformDisplayOpenVR::updateEyeParameters()
 {
     for (unsigned eye = 0; eye < VRPlatformDisplayInfo::NumEyes; ++eye) {
         auto platformEye = static_cast<VRPlatformDisplayInfo::Eye>(eye);
         m_displayInfo.setEyeFieldOfView(platformEye, computeFieldOfView(static_cast<vr::Hmd_Eye>(eye)));

         vr::HmdMatrix34_t eyeToHead = m_system->GetEyeToHeadTransform(static_cast<vr::Hmd_Eye>(eye));
         m_displayInfo.setEyeTranslation(platformEye, { eyeToHead.m[0][3], eyeToHead.m[1][3], eyeToHead.m[2][3] });
     }

     uint32_t width;
     uint32_t height;
     m_system->GetRecommendedRenderTargetSize(&width, &height);
     m_displayInfo.setRenderSize({ width, height });
 }

 void VRPlatformDisplayOpenVR::updateStageParameters()
 {
     float playAreaWidth = 1;
     float playAreaDepth = 1;
     if (!m_chaperone->GetPlayAreaSize(&playAreaWidth, &playAreaDepth)) {
         // Fallback to sensible values, 1mx1m play area and 0.75m high seated position. We do as
         // Firefox does.
         TransformationMatrix matrix;
         matrix.setM42(0.75);
         m_displayInfo.setSittingToStandingTransform(WTFMove(matrix));
     } else {
         vr::HmdMatrix34_t transformMatrix = m_system->GetSeatedZeroPoseToStandingAbsoluteTrackingPose();
         auto matrix =  TransformationMatrix(transformMatrix.m[0][0], transformMatrix.m[1][0], transformMatrix.m[2][0], 0,
             transformMatrix.m[0][1], transformMatrix.m[1][1], transformMatrix.m[2][1], 0,
             transformMatrix.m[0][2], transformMatrix.m[1][2], transformMatrix.m[2][2], 0,
             transformMatrix.m[0][3], transformMatrix.m[1][3], transformMatrix.m[2][3], 1);
         m_displayInfo.setSittingToStandingTransform(WTFMove(matrix));
     }
     m_displayInfo.setPlayAreaBounds(FloatSize(playAreaWidth, playAreaDepth));
 }

 // FIXME: we might want to generalize this function for other backends.
 static VRPlatformTrackingInfo::Quaternion rotationMatrixToQuaternion(const float (&matrix)[3][4])
 {
     // See https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2015/01/matrix-to-quat.pdf.
     VRPlatformTrackingInfo::Quaternion quaternion;
     float trace;
     if (matrix[2][2] < 0) {
         if (matrix[0][0] > matrix[1][1]) {
             trace = 1 + matrix[0][0] - matrix[1][1] - matrix[2][2];
             quaternion = { trace, matrix[0][1]+matrix[1][0], matrix[2][0]+matrix[0][2], matrix[1][2] - matrix[2][1] };
         } else {
             trace = 1 - matrix[0][0] + matrix[1][1] - matrix[2][2];
             quaternion = { matrix[0][1]+matrix[1][0], trace, matrix[1][2]+matrix[2][1], matrix[2][0] - matrix[0][2] };
         }
     } else {
         if (matrix[0][0] < -matrix[1][1]) {
             trace = 1 - matrix[0][0] - matrix[1][1] + matrix[2][2];
             quaternion = { matrix[2][0]+matrix[0][2], matrix[1][2]+matrix[2][1], trace , matrix[0][1] - matrix[1][0] };
         } else {
             trace = 1 + matrix[0][0] + matrix[1][1] + matrix[2][2];
             quaternion = { matrix[1][2] - matrix[2][1], matrix[2][0] - matrix[0][2], matrix[0][1] - matrix[1][0], trace };
         }
     }
     return quaternion * (0.5 / sqrt(trace));
 }

 VRPlatformTrackingInfo VRPlatformDisplayOpenVR::getTrackingInfo()
 {
     vr::TrackedDevicePose_t poses[vr::k_unMaxTrackedDeviceCount];

     m_compositor->WaitGetPoses(nullptr, 0, poses, vr::k_unMaxTrackedDeviceCount);

     m_trackingInfo.clear();

     vr::Compositor_FrameTiming timing;
     timing.m_nSize = sizeof(vr::Compositor_FrameTiming);
     m_compositor->GetFrameTiming(&timing);
     m_trackingInfo.timestamp = timing.m_flSystemTimeInSeconds;

     if (!poses[vr::k_unTrackedDeviceIndex_Hmd].bDeviceIsConnected
         || !poses[vr::k_unTrackedDeviceIndex_Hmd].bPoseIsValid
         || poses[vr::k_unTrackedDeviceIndex_Hmd].eTrackingResult != vr::TrackingResult_Running_OK) {
         // FIXME: Init some data maybe???.
         return m_trackingInfo;
     }

     const auto& HMDPose = poses[vr::k_unTrackedDeviceIndex_Hmd];
     const auto& transform = HMDPose.mDeviceToAbsoluteTracking;
     m_trackingInfo.orientation = rotationMatrixToQuaternion(transform.m);
     m_trackingInfo.orientation->conjugate();
     m_trackingInfo.position = FloatPoint3D(transform.m[0][3], transform.m[1][3], transform.m[2][3]);
     m_trackingInfo.angularVelocity = VRPlatformTrackingInfo::Float3(HMDPose.vAngularVelocity.v[0], HMDPose.vAngularVelocity.v[1], HMDPose.vAngularVelocity.v[2]);
     m_trackingInfo.linearVelocity = VRPlatformTrackingInfo::Float3(HMDPose.vVelocity.v[0], HMDPose.vVelocity.v[1], HMDPose.vVelocity.v[2]);

     return m_trackingInfo;
 }

 void VRPlatformDisplayOpenVR::updateDisplayInfo()
 {
     if (!vr::VR_IsHmdPresent())
         return;

     vr::VREvent_t event;
     while (m_system && m_system->PollNextEvent(&event, sizeof(event))) {
         switch (event.eventType) {
         case vr::VREvent_TrackedDeviceUserInteractionStarted:
         case vr::VREvent_TrackedDeviceUserInteractionEnded:
             if (event.trackedDeviceIndex == vr::k_unTrackedDeviceIndex_Hmd)
                 m_displayInfo.setIsMounted(event.eventType == vr::VREvent_TrackedDeviceUserInteractionStarted ? true : false);
             break;
         case vr::EVREventType::VREvent_TrackedDeviceActivated:
         case vr::EVREventType::VREvent_TrackedDeviceDeactivated:
             if (event.trackedDeviceIndex == vr::k_unTrackedDeviceIndex_Hmd)
                 m_displayInfo.setIsConnected(event.eventType == vr::VREvent_TrackedDeviceActivated ? true : false);
             break;
         case vr::EVREventType::VREvent_DriverRequestedQuit:
         case vr::EVREventType::VREvent_Quit:
         case vr::EVREventType::VREvent_ProcessQuit:
         case vr::EVREventType::VREvent_QuitAcknowledged:
         case vr::EVREventType::VREvent_QuitAborted_UserPrompt:
             // FIXME: should we notify the platform manager about this and call VR_Shutdown().
         default:
             break;
         }
     }
 }

 }; // namespace WebCore

 #endif // USE(OPENVR)
	/*
	* Copyright (C) 2018 Igalia, S.L. All right reserved.
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Library General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Library General Public License for more details.
	*
	* You should have received a copy of the GNU Library General Public License
	* along with this library; see the file COPYING.LIB. If not, write to
	* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*
	*/

	#include "config.h"
	#include "VRPlatformDisplayOpenVR.h"

	#if USE(OPENVR)

	#include <wtf/text/StringBuilder.h>

	namespace WebCore {

	uint32_t VRPlatformDisplayOpenVR::s_displayIdentifier = 0;

	VRPlatformDisplayOpenVR::VRPlatformDisplayOpenVR(vr::IVRSystem* system, vr::IVRChaperone* chaperone, vr::IVRCompositor* compositor)
	: m_system(system)
	, m_chaperone(chaperone)
	, m_compositor(compositor)
	{
	m_displayInfo.setDisplayIdentifier(++s_displayIdentifier);
	m_displayInfo.setIsConnected(m_system->IsTrackedDeviceConnected(vr::k_unTrackedDeviceIndex_Hmd));

	StringBuilder stringBuilder;
	stringBuilder.appendLiteral("OpenVR HMD");
	char HMDName[128];
	if (auto length = m_system->GetStringTrackedDeviceProperty(vr::k_unTrackedDeviceIndex_Hmd, vr::Prop_ManufacturerName_String, HMDName, 128)) {
	stringBuilder.append(" (");
	stringBuilder.append(HMDName, length);
	stringBuilder.append(')');
	}
	m_displayInfo.setDisplayName(stringBuilder.toString());
	m_displayInfo.setIsMounted(false);
	// FIXME: We're assuming an HTC Vive HMD here. Get this info from OpenVR?.
	m_displayInfo.setCapabilityFlags(VRDisplayCapabilityFlagNone \| VRDisplayCapabilityFlagPosition \| VRDisplayCapabilityFlagOrientation \| VRDisplayCapabilityFlagExternalDisplay \| VRDisplayCapabilityFlagPresent);

	m_compositor->SetTrackingSpace(vr::TrackingUniverseSeated);

	updateEyeParameters();
	updateStageParameters();
	}

	VRPlatformDisplayInfo::FieldOfView VRPlatformDisplayOpenVR::computeFieldOfView(vr::Hmd_Eye eye)
	{
	float left, right, top, bottom;
	// OpenVR returns the tangents of the half-angles from the center view axis.
	m_system->GetProjectionRaw(static_cast<vr::Hmd_Eye>(eye), &left, &right, &top, &bottom);
	return { -rad2deg(atanf(top)), rad2deg(atanf(bottom)), -rad2deg(atanf(left)), rad2deg(atanf(right)) };
	}

	void VRPlatformDisplayOpenVR::updateEyeParameters()
	{
	for (unsigned eye = 0; eye < VRPlatformDisplayInfo::NumEyes; ++eye) {
	auto platformEye = static_cast<VRPlatformDisplayInfo::Eye>(eye);
	m_displayInfo.setEyeFieldOfView(platformEye, computeFieldOfView(static_cast<vr::Hmd_Eye>(eye)));

	vr::HmdMatrix34_t eyeToHead = m_system->GetEyeToHeadTransform(static_cast<vr::Hmd_Eye>(eye));
	m_displayInfo.setEyeTranslation(platformEye, { eyeToHead.m[0][3], eyeToHead.m[1][3], eyeToHead.m[2][3] });
	}

	uint32_t width;
	uint32_t height;
	m_system->GetRecommendedRenderTargetSize(&width, &height);
	m_displayInfo.setRenderSize({ width, height });
	}

	void VRPlatformDisplayOpenVR::updateStageParameters()
	{
	float playAreaWidth = 1;
	float playAreaDepth = 1;
	if (!m_chaperone->GetPlayAreaSize(&playAreaWidth, &playAreaDepth)) {
	// Fallback to sensible values, 1mx1m play area and 0.75m high seated position. We do as
	// Firefox does.
	TransformationMatrix matrix;
	matrix.setM42(0.75);
	m_displayInfo.setSittingToStandingTransform(WTFMove(matrix));
	} else {
	vr::HmdMatrix34_t transformMatrix = m_system->GetSeatedZeroPoseToStandingAbsoluteTrackingPose();
	auto matrix = TransformationMatrix(transformMatrix.m[0][0], transformMatrix.m[1][0], transformMatrix.m[2][0], 0,
	transformMatrix.m[0][1], transformMatrix.m[1][1], transformMatrix.m[2][1], 0,
	transformMatrix.m[0][2], transformMatrix.m[1][2], transformMatrix.m[2][2], 0,
	transformMatrix.m[0][3], transformMatrix.m[1][3], transformMatrix.m[2][3], 1);
	m_displayInfo.setSittingToStandingTransform(WTFMove(matrix));
	}
	m_displayInfo.setPlayAreaBounds(FloatSize(playAreaWidth, playAreaDepth));
	}

	// FIXME: we might want to generalize this function for other backends.
	static VRPlatformTrackingInfo::Quaternion rotationMatrixToQuaternion(const float (&matrix)[3][4])
	{
	// See https://d3cw3dd2w32x2b.cloudfront.net/wp-content/uploads/2015/01/matrix-to-quat.pdf.
	VRPlatformTrackingInfo::Quaternion quaternion;
	float trace;
	if (matrix[2][2] < 0) {
	if (matrix[0][0] > matrix[1][1]) {
	trace = 1 + matrix[0][0] - matrix[1][1] - matrix[2][2];
	quaternion = { trace, matrix[0][1]+matrix[1][0], matrix[2][0]+matrix[0][2], matrix[1][2] - matrix[2][1] };
	} else {
	trace = 1 - matrix[0][0] + matrix[1][1] - matrix[2][2];
	quaternion = { matrix[0][1]+matrix[1][0], trace, matrix[1][2]+matrix[2][1], matrix[2][0] - matrix[0][2] };
	}
	} else {
	if (matrix[0][0] < -matrix[1][1]) {
	trace = 1 - matrix[0][0] - matrix[1][1] + matrix[2][2];
	quaternion = { matrix[2][0]+matrix[0][2], matrix[1][2]+matrix[2][1], trace , matrix[0][1] - matrix[1][0] };
	} else {
	trace = 1 + matrix[0][0] + matrix[1][1] + matrix[2][2];
	quaternion = { matrix[1][2] - matrix[2][1], matrix[2][0] - matrix[0][2], matrix[0][1] - matrix[1][0], trace };
	}
	}
	return quaternion * (0.5 / sqrt(trace));
	}

	VRPlatformTrackingInfo VRPlatformDisplayOpenVR::getTrackingInfo()
	{
	vr::TrackedDevicePose_t poses[vr::k_unMaxTrackedDeviceCount];

	m_compositor->WaitGetPoses(nullptr, 0, poses, vr::k_unMaxTrackedDeviceCount);

	m_trackingInfo.clear();

	vr::Compositor_FrameTiming timing;
	timing.m_nSize = sizeof(vr::Compositor_FrameTiming);
	m_compositor->GetFrameTiming(&timing);
	m_trackingInfo.timestamp = timing.m_flSystemTimeInSeconds;

	if (!poses[vr::k_unTrackedDeviceIndex_Hmd].bDeviceIsConnected
	\|\| !poses[vr::k_unTrackedDeviceIndex_Hmd].bPoseIsValid
	\|\| poses[vr::k_unTrackedDeviceIndex_Hmd].eTrackingResult != vr::TrackingResult_Running_OK) {
	// FIXME: Init some data maybe???.
	return m_trackingInfo;
	}

	const auto& HMDPose = poses[vr::k_unTrackedDeviceIndex_Hmd];
	const auto& transform = HMDPose.mDeviceToAbsoluteTracking;
	m_trackingInfo.orientation = rotationMatrixToQuaternion(transform.m);
	m_trackingInfo.orientation->conjugate();
	m_trackingInfo.position = FloatPoint3D(transform.m[0][3], transform.m[1][3], transform.m[2][3]);
	m_trackingInfo.angularVelocity = VRPlatformTrackingInfo::Float3(HMDPose.vAngularVelocity.v[0], HMDPose.vAngularVelocity.v[1], HMDPose.vAngularVelocity.v[2]);
	m_trackingInfo.linearVelocity = VRPlatformTrackingInfo::Float3(HMDPose.vVelocity.v[0], HMDPose.vVelocity.v[1], HMDPose.vVelocity.v[2]);

	return m_trackingInfo;
	}

	void VRPlatformDisplayOpenVR::updateDisplayInfo()
	{
	if (!vr::VR_IsHmdPresent())
	return;

	vr::VREvent_t event;
	while (m_system && m_system->PollNextEvent(&event, sizeof(event))) {
	switch (event.eventType) {
	case vr::VREvent_TrackedDeviceUserInteractionStarted:
	case vr::VREvent_TrackedDeviceUserInteractionEnded:
	if (event.trackedDeviceIndex == vr::k_unTrackedDeviceIndex_Hmd)
	m_displayInfo.setIsMounted(event.eventType == vr::VREvent_TrackedDeviceUserInteractionStarted ? true : false);
	break;
	case vr::EVREventType::VREvent_TrackedDeviceActivated:
	case vr::EVREventType::VREvent_TrackedDeviceDeactivated:
	if (event.trackedDeviceIndex == vr::k_unTrackedDeviceIndex_Hmd)
	m_displayInfo.setIsConnected(event.eventType == vr::VREvent_TrackedDeviceActivated ? true : false);
	break;
	case vr::EVREventType::VREvent_DriverRequestedQuit:
	case vr::EVREventType::VREvent_Quit:
	case vr::EVREventType::VREvent_ProcessQuit:
	case vr::EVREventType::VREvent_QuitAcknowledged:
	case vr::EVREventType::VREvent_QuitAborted_UserPrompt:
	// FIXME: should we notify the platform manager about this and call VR_Shutdown().
	default:
	break;
	}
	}
	}

	}; // namespace WebCore

	#endif // USE(OPENVR)