UnrealEngineUWP/Engine/Shaders/SlateDefaultPixelShader.usf

// Copyright 1998-2014 Epic Games, Inc. All Rights Reserved.


#include "Common.usf"


sampler2D ElementTexture;
uint DrawEffects;

struct VertexOut
{
	float4 Position : POSITION;
	float4 Color : COLOR0;
	float4 TextureCoordinates : TEXCOORD0;
	float4 ClipCoords : TEXCOORD1;
	float2 SSPosition : TEXCOORD2;
};

float4 Main( VertexOut VIn ) : COLOR0
{
	
	// Clip pixels which are outside of the clipping rect
	clip( float4( VIn.SSPosition.x - VIn.ClipCoords.x, VIn.ClipCoords.z - VIn.SSPosition.x, VIn.SSPosition.y - VIn.ClipCoords.y, VIn.ClipCoords.w - VIn.SSPosition.y ) );


	float4 OutColor = VIn.Color;
	OutColor *= tex2D(ElementTexture, VIn.TextureCoordinates.xy*VIn.TextureCoordinates.zw);

	if( DrawEffects != 0 )
	{
		//desaturate
		float3 LumCoeffs = float3( 0.3, 0.59, .11 );
		float Lum = dot( LumCoeffs, OutColor.rgb );
		OutColor.rgb = lerp( OutColor.rgb, float3(Lum,Lum,Lum), .8 );
	
		float3 Grayish = {.4, .4, .4};
	
		OutColor.rgb = lerp( OutColor.rgb, Grayish, clamp( distance( OutColor.rgb, Grayish ), 0, .8)  );
	}

	return OutColor;
}