UISurfaceActor.cpp

/*****************************
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#include "OculusUIPOC.h"

#include "CoherentUIComponent.h"
#include <Coherent/UI/InputEvents.h>
#include <Coherent/UI/View.h>
#include "DrawDebugHelpers.h"
#include "Engine.h"
#include "Runtime/Core/Public/Misc/DateTime.h"
#include <string>
#include "StringConv.h"
#include "UISurfaceActor.h"

AUISurfaceActor::AUISurfaceActor(const class FPostConstructInitializeProperties& PCIP)
	: Super(PCIP)
{
	UIViewInitialized = false;
	HoverDistance = 30.0;
	LastMouseEventPixelCoordinates = *(new FVector());

	UISurfaceMesh = PCIP.CreateDefaultSubobject<UStaticMeshComponent>(this, TEXT("UISurfaceMesh"));
	RootComponent = UISurfaceMesh;
	CoherentUIComponent = PCIP.CreateDefaultSubobject<UCoherentUIComponent>(this, TEXT("UCoherentUIComponent"));
	CoherentUIViewURL = TEXT("http://www.google.com");
	CoherentUIViewPixelWidth = 1024;
	// enable tick
	PrimaryActorTick.bCanEverTick = true;
	PrimaryActorTick.bStartWithTickEnabled = true;
	PixelToWheelTickScalingFactor = 100.0; // looks like a full wheel tick is approximately 100 pixels (9 or 10 wheel ticks to scroll 1024 pixels)
	ScrollNumPixelsThreshold = 3.0;
	SwipeLengthPixelsThreshold = 40.0;
	SwipeWidthPixelsCutoff = 10.0;
	MinMillisecondsBetweenSwipes = 500;
	MaxMillisecondsLinkingSwipes = 1500;

	LastLeftSwipeTime = FDateTime::Now(); // initialize swipe time
	LastRightSwipeTime = FDateTime::Now(); // initialize swipe time
}

void AUISurfaceActor::HandleMouseoverEventWorldLocation(FVector EventWorldLocation)
{
	if (!PointerFingerIsHovering) { // don't handle raycast mouseover if in hover state
		Coherent::UI::View* UIView = CoherentUIComponent->GetView();
		if (UIView) {
			// Get XY pixel coordinates in the UI View
			LastMouseEventPixelCoordinates = GetViewPixelCoordinatesFromWorldLocation(EventWorldLocation);
			HandleMouseoverEventPixelCoordinates(LastMouseEventPixelCoordinates);
		}
	}
}

void AUISurfaceActor::HandleMouseoverEventPixelCoordinates(FVector PixelCoordinates)
{
	Coherent::UI::View* UIView = CoherentUIComponent->GetView();
	if (UIView) {
		// Generate view mouse events from user input
		Coherent::UI::MouseEventData* UIMouseEvent = new Coherent::UI::MouseEventData();
		UIMouseEvent->X = PixelCoordinates.X;
		UIMouseEvent->Y = PixelCoordinates.Y;
		UIMouseEvent->Type = Coherent::UI::MouseEventData::EventType::MouseMove;
		UIView->MouseEvent(*UIMouseEvent);
	}
}

void AUISurfaceActor::HandleMouseDownEventAtCoordinates(FVector PixelCoordinates)
{
	Coherent::UI::MouseEventData* UIMouseEvent = new Coherent::UI::MouseEventData();
	UIMouseEvent->Type = Coherent::UI::MouseEventData::EventType::MouseDown;
	UIMouseEvent->X = PixelCoordinates.X;
	UIMouseEvent->Y = PixelCoordinates.Y;
	CoherentUIComponent->GetView()->MouseEvent(*UIMouseEvent);
}

void AUISurfaceActor::HandleMouseDownEvent()
{
	HandleMouseDownEventAtCoordinates(LastMouseEventPixelCoordinates);
}

void AUISurfaceActor::HandleMouseUpEventAtCoordinates(FVector PixelCoordinates)
{
	Coherent::UI::MouseEventData* UIMouseEvent = new Coherent::UI::MouseEventData();
	UIMouseEvent->Type = Coherent::UI::MouseEventData::EventType::MouseUp;
	UIMouseEvent->X = PixelCoordinates.X;
	UIMouseEvent->Y = PixelCoordinates.Y;
	CoherentUIComponent->GetView()->MouseEvent(*UIMouseEvent);
}

void AUISurfaceActor::HandleMouseUpEvent()
{
	HandleMouseUpEventAtCoordinates(LastMouseEventPixelCoordinates);
}

void AUISurfaceActor::HandleMouseClick(FVector ViewPixelCoordinates)
{
	HandleMouseDownEventAtCoordinates(ViewPixelCoordinates);
	HandleMouseUpEventAtCoordinates(ViewPixelCoordinates);
}


void AUISurfaceActor::HandleYScrollIncrementEvent(float NumYWheelTicksWithSign)
{
	Coherent::UI::MouseEventData* UIMouseEvent = new Coherent::UI::MouseEventData();
	UIMouseEvent->Type = Coherent::UI::MouseEventData::EventType::MouseWheel;
	UIMouseEvent->WheelY = NumYWheelTicksWithSign;
	CoherentUIComponent->GetView()->MouseEvent(*UIMouseEvent);
}

void AUISurfaceActor::HandleScrollDownEvent()
{
	HandleYScrollIncrementEvent(-1.0);
}

void AUISurfaceActor::HandleScrollUpEvent()
{
	HandleYScrollIncrementEvent(1.0);
}

void AUISurfaceActor::HandleBackEvent()
{
	Coherent::UI::View* UIView = CoherentUIComponent->GetView();
	if (UIView) {
		UIView->ExecuteScript("history.back();");
	}
}

void AUISurfaceActor::HandleVirtualTouchInput(FVector ActionHandPalmLocation, FVector ActionHandFingerLocation) {
	FVector ActorSpaceActionFingerLocation = this->GetTransform().InverseTransformPosition(ActionHandFingerLocation);
	FVector ActorSpaceActionPalmLocation = this->GetTransform().InverseTransformPosition(ActionHandPalmLocation);
	FVector ActorSpaceActionFingerPreviousLocation = this->GetTransform().InverseTransformPosition(ActionHandPreviousFingerLocation);
	FVector ActorSpaceActionPalmPreviousLocation = this->GetTransform().InverseTransformPosition(ActionHandPreviousPalmLocation);
	FVector ActorSpaceActionFingerLocationXY = ActorSpaceActionFingerLocation;
	ActorSpaceActionFingerLocationXY.Z = 0.0;
	FVector ActorSpacePointerFingerLocationXYWorld = this->GetTransform().TransformPosition(ActorSpaceActionFingerLocationXY);
	FVector PointerFingerPixelCoordinates = GetViewPixelCoordinatesFromActorLocation(ActorSpaceActionFingerLocationXY);
	if (ActorSpaceActionFingerLocation.Z <= 0) { // finger is across plane
		if (!PointerFingerAcrossPlane) { // finger was not previously across plane, so handle as mouse click and set across flag to true
			HandleMouseDownEventAtCoordinates(PointerFingerPixelCoordinates);
			DrawDebugSphere(GetWorld(), ActorSpacePointerFingerLocationXYWorld, 0.6, 12, FColor::Cyan, true, 0.1);
			PointerFingerAcrossPlane = true;
		}
		else { // was already across plane
		}
		// handle scrolling
		FVector CurrentPalmPixelCoordinates = GetViewPixelCoordinatesFromActorLocation(ActorSpaceActionPalmLocation);
		FVector PreviousPalmPixelCoordinates = GetViewPixelCoordinatesFromActorLocation(ActorSpaceActionPalmPreviousLocation);
		float NumPixelsMovedY = CurrentPalmPixelCoordinates.Y - PreviousPalmPixelCoordinates.Y; // if negative means palm is moving up so should scroll down
		if (abs(NumPixelsMovedY) >= ScrollNumPixelsThreshold) {
			float WheelTicksY = NumPixelsMovedY / PixelToWheelTickScalingFactor;
			HandleYScrollIncrementEvent(WheelTicksY);
		}
		// Handle left/right swipe
		// NOTE: was a simple left swipe to go Back before, but since there were too many false positives have more complicated gesture linking left and right swipes to go Back
		float NumPixelsMovedX = CurrentPalmPixelCoordinates.X - PreviousPalmPixelCoordinates.X; 
		if (abs(NumPixelsMovedX) >= SwipeLengthPixelsThreshold) { 
			FDateTime CurrentTime = FDateTime::Now();
			if (NumPixelsMovedX < 0) { // is left swipe
				FTimespan TimeBetweenLeftSwipes = CurrentTime - LastLeftSwipeTime;
				if (TimeBetweenLeftSwipes.GetTotalMilliseconds() >= MinMillisecondsBetweenSwipes) { // check if there has been enough elapsed time since last swipe
					LastLeftSwipeTime = CurrentTime;
				}
			}
			else { // is right swipe
				FTimespan TimeBetweenRightSwipes = CurrentTime - LastRightSwipeTime;
				if (TimeBetweenRightSwipes.GetTotalMilliseconds() >= MinMillisecondsBetweenSwipes) { // check if there has been enough elapsed time since last swipe
					LastRightSwipeTime = CurrentTime;
					FTimespan TimeBetweenLeftAndRightSwipes = LastRightSwipeTime - LastLeftSwipeTime;
					if (TimeBetweenLeftAndRightSwipes.GetTotalMilliseconds() <= MaxMillisecondsLinkingSwipes) { // check right swipe is linked to the previous left swipe
						HandleBackEvent();
					}
				}
			}
		}
		
	}
	else { // finger is not across plane
		if (PointerFingerAcrossPlane) { // set across flag to false if it was set to true
			PointerFingerAcrossPlane = false ;
			HandleMouseUpEventAtCoordinates(PointerFingerPixelCoordinates);
		}
		// check for hover state
		if (ActorSpaceActionFingerLocation.Z <= this->HoverDistance) { // check for hovering
			PointerFingerIsHovering = true;
			DrawDebugSphere(GetWorld(), ActorSpacePointerFingerLocationXYWorld, 0.5, 12, FColor::Magenta);
			HandleMouseoverEventPixelCoordinates(PointerFingerPixelCoordinates);
		}
		else {
			if (PointerFingerIsHovering) {
				PointerFingerIsHovering = false;
			}
		}
	}
    // Now that we are done with Leap processing let's set the previous hand locations to the current hand locations
    ActionHandPreviousPalmLocation = ActionHandPalmLocation;
    ActionHandPreviousFingerLocation = ActionHandFingerLocation;
}

FVector AUISurfaceActor::GetViewPixelCoordinatesFromWorldLocation(FVector WorldLocation) {
	FVector* ViewPixelCoordinates = new FVector();
	FVector ActorLocation = this->GetTransform().InverseTransformPosition(WorldLocation);
	return GetViewPixelCoordinatesFromActorLocation(ActorLocation);
}

FVector AUISurfaceActor::GetViewPixelCoordinatesFromActorLocation(FVector ActorLocation) {
	FVector* ViewPixelCoordinates = new FVector();
	float NormalizedUIViewX = (ActorLocation.X + 50.0) / 100.0;
	float NormalizedUIViewY = (ActorLocation.Y + 50.0) / 100.0;
	ViewPixelCoordinates->X = NormalizedUIViewX * CoherentUIComponent->GetView()->GetWidth();
	ViewPixelCoordinates->Y = NormalizedUIViewY * CoherentUIComponent->GetView()->GetHeight();
	ViewPixelCoordinates->Z = 0.0;
	return *ViewPixelCoordinates;
}

void AUISurfaceActor::Tick(float DeltaTime)
{

}

void AUISurfaceActor::InitializeView()
{
	CoherentUIComponent.Get()->URL = CoherentUIViewURL;
	float AspectRatio = this->GetActorScale().X / this->GetActorScale().Y;
	CoherentUIComponent.Get()->Width = CoherentUIViewPixelWidth;
	CoherentUIComponent.Get()->Height = CoherentUIViewPixelWidth / AspectRatio;

}

void AUISurfaceActor::ResetFlags()
{
	PointerFingerIsHovering = false;
	PointerFingerAcrossPlane = false;
}

