void FSteamVRHMD::PreRenderView_RenderThread(FRHICommandListImmediate& RHICmdList, FSceneView& View)
{
check(IsInRenderingThread());
// The last view location used to set the view will be in BaseHmdOrientation. We need to calculate the delta from that, so that
// cameras that rely on game objects (e.g. other components) for their positions don't need to be updated on the render thread.
const FQuat DeltaOrient = View.BaseHmdOrientation.Inverse() * TrackingFrame.DeviceOrientation[vr::k_unTrackedDeviceIndex_Hmd];
View.ViewRotation = FRotator(View.ViewRotation.Quaternion() * DeltaOrient);
View.UpdateViewMatrix();
}
void FViewExtension::PreRenderView_RenderThread(FRHICommandListImmediate& RHICmdList, FSceneView& View)
{
check(IsInRenderingThread());
FViewExtension& RenderContext = *this;
FGameFrame* CurrentFrame = static_cast<FGameFrame*>(RenderContext.RenderFrame.Get());
if (!RenderContext.ShowFlags.Rendering || !CurrentFrame || !CurrentFrame->Settings->IsStereoEnabled())
{
return;
}
const ovrEyeType eyeIdx = (View.StereoPass == eSSP_LEFT_EYE) ? ovrEye_Left : ovrEye_Right;
if (RenderContext.ShowFlags.Rendering && CurrentFrame->Settings->Flags.bUpdateOnRT)
{
FQuat CurrentEyeOrientation;
FVector CurrentEyePosition;
CurrentFrame->PoseToOrientationAndPosition(RenderContext.CurEyeRenderPose[eyeIdx], CurrentEyeOrientation, CurrentEyePosition);
FQuat ViewOrientation = View.ViewRotation.Quaternion();
// recalculate delta control orientation; it should match the one we used in CalculateStereoViewOffset on a game thread.
FVector GameEyePosition;
FQuat GameEyeOrient;
CurrentFrame->PoseToOrientationAndPosition(CurrentFrame->EyeRenderPose[eyeIdx], GameEyeOrient, GameEyePosition);
const FQuat DeltaControlOrientation = ViewOrientation * GameEyeOrient.Inverse();
// make sure we use the same viewrotation as we had on a game thread
check(View.ViewRotation == CurrentFrame->CachedViewRotation[eyeIdx]);
if (CurrentFrame->Flags.bOrientationChanged)
{
// Apply updated orientation to corresponding View at recalc matrices.
// The updated position will be applied from inside of the UpdateViewMatrix() call.
const FQuat DeltaOrient = View.BaseHmdOrientation.Inverse() * CurrentEyeOrientation;
View.ViewRotation = FRotator(ViewOrientation * DeltaOrient);
//UE_LOG(LogHMD, Log, TEXT("VIEWDLT: Yaw %.3f Pitch %.3f Roll %.3f"), DeltaOrient.Rotator().Yaw, DeltaOrient.Rotator().Pitch, DeltaOrient.Rotator().Roll);
}
if (!CurrentFrame->Flags.bPositionChanged)
{
// if no positional change applied then we still need to calculate proper stereo disparity.
// use the current head pose for this calculation instead of the one that was saved on a game thread.
FQuat HeadOrientation;
CurrentFrame->PoseToOrientationAndPosition(RenderContext.CurHeadPose, HeadOrientation, View.BaseHmdLocation);
}
// The HMDPosition already has HMD orientation applied.
// Apply rotational difference between HMD orientation and ViewRotation
// to HMDPosition vector.
const FVector DeltaPosition = CurrentEyePosition - View.BaseHmdLocation;
const FVector vEyePosition = DeltaControlOrientation.RotateVector(DeltaPosition) + CurrentFrame->Settings->PositionOffset;
View.ViewLocation += vEyePosition;
//UE_LOG(LogHMD, Log, TEXT("VDLTPOS: %.3f %.3f %.3f"), vEyePosition.X, vEyePosition.Y, vEyePosition.Z);
if (CurrentFrame->Flags.bOrientationChanged || CurrentFrame->Flags.bPositionChanged)
{
View.UpdateViewMatrix();
}
}
FSettings* FrameSettings = CurrentFrame->GetSettings();
check(FrameSettings);
FrameSettings->EyeLayer.EyeFov.RenderPose[eyeIdx] = RenderContext.CurEyeRenderPose[eyeIdx];
}