Slate - How to setup absolute widget position in Viewport.

Development Programming & Scripting C++
1

I have this code:


// Copyright 1998-2016 Epic Games, Inc. All Rights Reserved.

#include "FloatingCombatText.h"
#include "STextBlock.h"
#include "SConstraintCanvas.h"
#include "SFCTItem.h"

void SFCTItem::Construct(const FArguments& InArgs)
{
	PositionDel.Bind(this, &SFCTItem::GetPosition);
	AccumulatedLifeTime = 0;
	ChildSlot
		
			SNew(SConstraintCanvas)
			+ SConstraintCanvas::Slot()
			.AutoSize(true).Alignment(PositionDel)
			
				
					SNew(STextBlock)
					.Text(this, &SFCTItem::GetText)
			]
		];
}
void SFCTItem::Tick(const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime)
{
	FVector2D Pos;
	Pos = Position;// AllottedGeometry.AbsoluteToLocal(Position);
	LocalPos = Pos;
	
	if (GetVisibility() == EVisibility::Visible)
	{
		AccumulatedLifeTime += InDeltaTime;
		if (AccumulatedLifeTime > 3)
		{
			SetVisibility(EVisibility::Collapsed);
		}
	}
}
void SFCTItem::ShowWidget(const FVector& Location) const
{
	FVector2D OutScreenPos;
	if (PlayerController.IsValid())
	{
		PlayerController->ProjectWorldLocationToScreen(Location, OutScreenPos);
	}
}
FText SFCTItem::GetText() const
{
	return FText::FromString("Sample Text");
}
FVector2D SFCTItem::GetPosition() const
{
	return LocalPos;
}

It’s widget I want to setup position in space.

And here is code for manager widget:



// Copyright 1998-2016 Epic Games, Inc. All Rights Reserved.

#include "FloatingCombatText.h"
#include "SFCTContainer.h"

void SFCTContainer::Construct(const FArguments& InArgs)
{
	PC = InArgs._PC;
	PoolSize = InArgs._PoolSize;
	//ItemCanvas = SNew(SCanvas);

	for(int32 Idx = 0; Idx < PoolSize; Idx++)
	{
		TSharedPtr<SFCTItem> NewItem = SNew(SFCTItem);
		GEngine->GameViewport->AddViewportWidgetContent(NewItem.ToSharedRef());
		//ItemCanvas->AddSlot().AttachWidget(NewItem.ToSharedRef());
		ItemsPool.Add(NewItem);
		NewItem->SetVisibility(EVisibility::Collapsed);

	}
	//ItemCanvas->AddSlot().HAlign(HAlign_Fill).VAlign(VAlign_Fill);
	//GEngine->GameViewport->AddViewportWidgetContent(ItemCanvas.ToSharedRef());
}

void SFCTContainer::ShowText(const FVector& Position, const FString& TextIn)
{
	if(ItemsPool.Num() > 0)
	{
		FVector2D OutPosition;
		PC->ProjectWorldLocationToScreen(Position, OutPosition);
		FSlateRenderTransform NewTransform(5, OutPosition);
		ItemsPool[0]->Position = OutPosition;
		ItemsPool[0]->AccumulatedLifeTime = 0;
		ItemsPool[0]->SetVisibility(EVisibility::Visible);
	}
}

I want to set absolute position in viewport for SFCTItem . After 3 days of trying I can honestly say I have no idea what doing anymore.
I know it’s quite trivial to do in UMG, but I for the sake of science I want to do it in Slate.

2

If I remember correctly, after + SConstraintCanvas::Slot(), try this:
.Offset(TAttribute<FMargin>::Create(TAttribute<FMargin>::FGetter::CreateSP(this, &SFCTItem::GetPosition, i)))
and GetPosition must return FMargin

If that doesn’t do it, just look for examples in the engine sources, there’s plenty of them.