/**
 * @ Version: SCREEN SPACE SHADERS - UPDATE 17
 * @ Description: Rain Shader - VS
 * @ Modified time: 2023-06-26 06:47
 * @ Author: https://www.moddb.com/members/ascii1457
 * @ Mod: https://www.moddb.com/mods/stalker-anomaly/addons/screen-space-shaders
 */

#include "screenspace_common.h"

// Pixel Struct
struct p_Rain
{
	float2 Tex0	 : TEXCOORD0;
	float4 tc	 : TEXCOORD1;
};

float4 ssfx_rain_setup;

float4 main ( p_Rain I ) : SV_Target
{
	// Screen Space
	float2 PosTc = I.tc.xy / I.tc.w;

	// Normal Setup
	float4 N0 = s_base.Sample( smp_base, I.Tex0 );
	N0.xy = N0.xy * 2.0f - 1.0f; // Convert to -1.0f ~ 1.0f

	// Adjust "refraction" Intensity
	N0.xy = normalize(float3(N0.xy * 0.05f * ssfx_rain_setup.y, 1.0f));

	// Screen Buffer
	float3 Screen = SSFX_get_image(saturate(PosTc + N0.xy), 0);

	return float4( Screen, N0.w * ssfx_rain_setup.x );
}