fCraft's Spatial Filter

#version 330
in vec2 TexCoord;
out vec3 Color;

uniform sampler2D Input;
uniform sampler2D BlockTexCoord;
uniform sampler2D Normals;
uniform sampler2D WorldPos;
uniform sampler2D TemporalSampling;

uniform mat4 ProjectionMatrix;
uniform mat4 ViewMatrix;

uniform bool Vertical;

const int Pixels = 16;


void main() {

    vec2 TextureSize = vec2(textureSize(Input, 0));
    vec2 TexelSize = 1.0 / TextureSize;
    float TotalPixelsFound = 0.0;

    vec3 CurrentInput = texture(Input, TexCoord).xyz;

    float CurrentTemporalSampling = texture(TemporalSampling, TexCoord).x;



    Color = texture(Normals, TexCoord).xyz == vec3(0.) ? CurrentInput : vec3(0.);
    if (Color.r > 0.001 || Color.g > 0.001 || Color.b > 0.001)
        return;

    vec4 CurrentWorldPosition = texture(WorldPos, TexCoord);

    vec3 WorldPosPositive = texture(WorldPos, TexCoord + vec2(!Vertical ? TexelSize.x : 0.0, Vertical ? TexelSize.y : 0.0)).xyz;
    vec3 WorldPosNegative = texture(WorldPos, TexCoord - vec2(!Vertical ? TexelSize.x : 0.0, Vertical ? TexelSize.y : 0.0)).xyz;

    vec3 RayDirectionPositive = normalize(WorldPosPositive - CurrentWorldPosition.xyz);
    vec3 RayDirectionNegative = normalize(WorldPosPositive - CurrentWorldPosition.xyz);

    vec4 NewWorldPositionPositive = vec4(CurrentWorldPosition.xyz + RayDirectionPositive*0.5, 1.);
    vec4 NewWorldPositionNegative = vec4(CurrentWorldPosition.xyz + RayDirectionNegative*0.5, 1.);

    vec4 NDCPositive = ProjectionMatrix * ViewMatrix * NewWorldPositionPositive;
    vec2 TCPositive = (NDCPositive.xy / NDCPositive.w) * 0.5 + 0.5;

    vec4 NDCNegative = ProjectionMatrix * ViewMatrix * NewWorldPositionPositive;
    vec2 TCNegative = (NDCNegative.xy / NDCNegative.w) * 0.5 + 0.5;

    int RangeNegative = min(max(Vertical ? int(floor(abs(TCNegative.y - TexCoord.y) * TextureSize.y)) : int(floor(abs(TCNegative.x - TexCoord.x) * TextureSize.x)), int(ceil(mix(10.0, 7.0, CurrentTemporalSampling)))), int(ceil(mix(32.0, 24.0, CurrentTemporalSampling))));
    int RangePositive = min(max(Vertical ? int(floor(abs(TCPositive.y - TexCoord.y) * TextureSize.y)) : int(floor(abs(TCPositive.x - TexCoord.x) * TextureSize.x)), int(ceil(mix(10.0, 7.0, CurrentTemporalSampling)))), int(ceil(mix(32.0, 24.0, CurrentTemporalSampling))));

    float PowerCoef = mix(0.025, 0.05, CurrentTemporalSampling);

    vec4 PrevWorldPos = CurrentWorldPosition;

    float PixelAddon = 0.0;

    float Power = 1.0;

    for (int Pixel = -1; Pixel > RangeNegative; Pixel--) {

        Power -= PowerCoef;

        vec2 Addon = vec2(!Vertical ? TexelSize.x * Pixel : 0., Vertical ? TexelSize.y * Pixel : 0.);
        vec2 NC = TexCoord + Addon;

        vec4 ThisWorldPos = texture(WorldPos, NC);



        if (abs(ThisWorldPos.x - PrevWorldPos.x) > 0.6 || abs(ThisWorldPos.y - PrevWorldPos.y) > 0.6 || abs(ThisWorldPos.z - PrevWorldPos.z) > 0.6 || abs(ThisWorldPos.a - PrevWorldPos.a) > 0.1)
            break;

        PrevWorldPos = ThisWorldPos;

        vec3 c = texture(Input, NC).rgb;

        Color += texture(Input, NC).rgb * Power;



        PixelAddon += 1.0 * Power;

    }

    PrevWorldPos = CurrentWorldPosition;

    Power = 1.0;

    for (int Pixel = 1; Pixel < RangePositive; Pixel++) {

        Power -= PowerCoef;

        vec2 Addon = vec2(!Vertical ? TexelSize.x * Pixel : 0., Vertical ? TexelSize.y * Pixel : 0.);
        vec2 NC = TexCoord + Addon;

        vec4 ThisWorldPos = texture(WorldPos, NC);



        if (abs(ThisWorldPos.x - PrevWorldPos.x) > 0.6 || abs(ThisWorldPos.y - PrevWorldPos.y) > 0.6 || abs(ThisWorldPos.z - PrevWorldPos.z) > 0.6 || abs(ThisWorldPos.a - PrevWorldPos.a) > 0.1)
            break;

        PrevWorldPos = ThisWorldPos;

        //float Power = pow(PowerCoef, Pixel);

        vec3 c = texture(Input, NC).rgb;

        Color += texture(Input, NC).rgb * Power;

        PixelAddon += 1.0 * Power;

    }



    Color = PixelAddon < 0.1 ? CurrentInput : Color / PixelAddon;

}