//========== Copyright (c) Valve Corporation, All rights reserved. ==========//

sampler g_sBase	: register( s0 );

float g_flAlpha : register( c0 );
float g_flDesaturate : register( c1 );
float3 g_vColorFade : register( c2 );

struct PS_INPUT
{
	float2 uv : TEXCOORD0;
};

float4 main( PS_INPUT i ) : COLOR0
{
	// Fetch blurred texel
	float4 o = tex2D( g_sBase, i.uv );

	// Desaturate
	float3 tmpv = { 0.2125, 0.7154, 0.0721 };
	float flLuminance = dot( o.rgb, tmpv.rgb );
	o.rgb = lerp( o.rgb, flLuminance, saturate( g_flDesaturate ) );

	// Color fade
	o.rgb *= g_vColorFade.rgb;

	// Set alpha blend value
	o.a = g_flAlpha;

	return o;
}