/* Copyright (C) 2021 Hugo ATTAL - All Rights Reserved
* This plugin is downloadable from the Unreal Engine Marketplace
*/

#include "lib/Shapes.usf"

struct DarkerUIHeaderBox
{
	static float4 ComputeHeaderBox(float2 PixelSize, float2 UVs, float4 BackgroundColor, float4 BorderColor, float Radius, float4 Padding)
	{
		float2 Location = UVs * PixelSize;
		
		PixelSize.x -= Padding.x + Padding.z;
		PixelSize.y -= Padding.y + Padding.w;
		Location.x -= Padding.x;
		Location.y -= Padding.y;
		
		Radius = min(Radius, min(PixelSize.x, PixelSize.y) / 2 - 2);

		const float ExternalRectangle = DarkerUIShapes::IsInRoundedHeader(Location, float2(1, 1), PixelSize - float2(1, 1), Radius + 1);
		const float InternalRectangle = DarkerUIShapes::IsInRoundedHeader(Location, float2(2, 2), PixelSize - float2(2, 2), Radius);

		const float Alpha = lerp(
			ExternalRectangle * BorderColor.a, BackgroundColor.a,
			InternalRectangle);
		const float3 Color = lerp(
			BorderColor.rgb, BackgroundColor.rgb,
			InternalRectangle);
		
		return float4(Color, Alpha);
	}
};

/*
#include "/DarkerNodes/HeaderBox.usf"
return DarkerUIHeaderBox::ComputeHeaderBox(PixelSize, UVs, BackgroundColor, BorderColor, Radius, Padding);
*/