VRTrackedParentInterface.h

Go to the documentation of this file.

// Fill out your copyright notice in the Description page of Project Settings.
 
#pragma once
#include "CoreMinimal.h"
#include "VRBPDatatypes.h"
#include "UObject/ObjectMacros.h"
#include "UObject/ScriptMacros.h"
#include "UObject/Interface.h"
 
#include "VRTrackedParentInterface.generated.h"
 
 
UINTERFACE(MinimalAPI, meta = (CannotImplementInterfaceInBlueprint))
class UVRTrackedParentInterface: public UInterface
{
    GENERATED_UINTERFACE_BODY()
};
 
 
class VREXPANSIONPLUGIN_API IVRTrackedParentInterface
{
    GENERATED_IINTERFACE_BODY()
 
public:
 
    // Set a tracked parent
    UFUNCTION(BlueprintCallable, Category = "VRTrackedParentInterface")
    virtual void SetTrackedParent(UPrimitiveComponent * NewParentComponent, float WaistRadius, EBPVRWaistTrackingMode WaistTrackingMode)
    {}
 
    static void Default_SetTrackedParent_Impl(UPrimitiveComponent * NewParentComponent, float WaistRadius, EBPVRWaistTrackingMode WaistTrackingMode, FBPVRWaistTracking_Info & OptionalWaistTrackingParent, USceneComponent * Self)
    {
        // If had a different original tracked parent
        // Moved this to first thing so the pre-res is removed prior to erroring out and clearing this
        if (OptionalWaistTrackingParent.IsValid())
        {
            // Remove the tick Prerequisite
            Self->RemoveTickPrerequisiteComponent(OptionalWaistTrackingParent.TrackedDevice);
        }
 
        if (!NewParentComponent || !Self)
        {
            OptionalWaistTrackingParent.Clear();
            return;
        }
 
        // Make other component tick first if possible, waste of time if in wrong tick group
        if (NewParentComponent->PrimaryComponentTick.TickGroup == Self->PrimaryComponentTick.TickGroup)
        {
            // Make sure the other component isn't depending on this one
            NewParentComponent->RemoveTickPrerequisiteComponent(Self);
 
            // Add a tick pre-res for ourselves so that we tick after our tracked parent.
            Self->AddTickPrerequisiteComponent(NewParentComponent);
        }
 
        OptionalWaistTrackingParent.TrackedDevice = NewParentComponent;
        OptionalWaistTrackingParent.RestingRotation = NewParentComponent->GetRelativeRotation();
        OptionalWaistTrackingParent.RestingRotation.Yaw = 0.0f;
        
        OptionalWaistTrackingParent.TrackingMode = WaistTrackingMode;
        OptionalWaistTrackingParent.WaistRadius = WaistRadius;
    }
 
    // Returns local transform of the parent relative attachment
    static FTransform Default_GetWaistOrientationAndPosition(FBPVRWaistTracking_Info & WaistTrackingInfo)
    {
        if (!WaistTrackingInfo.IsValid())
            return FTransform::Identity;
 
        FTransform DeviceTransform = WaistTrackingInfo.TrackedDevice->GetRelativeTransform();
 
        // Rewind by the initial rotation when the new parent was set, this should be where the tracker rests on the person
        DeviceTransform.ConcatenateRotation(WaistTrackingInfo.RestingRotation.Quaternion().Inverse());
        DeviceTransform.SetScale3D(FVector(1, 1, 1));
 
        // Don't bother if not set
        if (WaistTrackingInfo.WaistRadius > 0.0f)
        {
            DeviceTransform.AddToTranslation(DeviceTransform.GetRotation().RotateVector(FVector(-WaistTrackingInfo.WaistRadius, 0, 0)));
        }
 
 
        // This changes the forward vector to be correct
        // I could pre do it by changed the yaw in resting mode to these values, but that had its own problems
        // If given an initial forward vector that it should align to I wouldn't have to do this and could auto calculate it.
        // But without that I am limited to this.
 
        // #TODO: add optional ForwardVector to initial setup function that auto calculates offset so that the user can pass in HMD forward or something for calibration X+
        // Also would be better overall because slightly offset from right angles in yaw wouldn't matter anymore, it would adjust for it.
        switch (WaistTrackingInfo.TrackingMode)
        {
        case EBPVRWaistTrackingMode::VRWaist_Tracked_Front: DeviceTransform.ConcatenateRotation(FRotator(0, 0, 0).Quaternion()); break;
        case EBPVRWaistTrackingMode::VRWaist_Tracked_Rear: DeviceTransform.ConcatenateRotation(FRotator(0, -180, 0).Quaternion()); break;
        case EBPVRWaistTrackingMode::VRWaist_Tracked_Left: DeviceTransform.ConcatenateRotation(FRotator(0, 90, 0).Quaternion()); break;
        case EBPVRWaistTrackingMode::VRWaist_Tracked_Right: DeviceTransform.ConcatenateRotation(FRotator(0, -90, 0).Quaternion()); break;
        }
        
        return DeviceTransform;
    }
};