export default /* glsl */` uniform sampler2D shadow_pass; uniform vec2 resolution; uniform float radius; #include void main() { float mean = 0.0; float squared_mean = 0.0; // This seems totally useless but it's a crazy work around for a Adreno compiler bug float depth = unpackRGBAToDepth( texture2D( shadow_pass, ( gl_FragCoord.xy ) / resolution ) ); for ( float i = -1.0; i < 1.0 ; i += SAMPLE_RATE) { #ifdef HORIZONAL_PASS vec2 distribution = unpackRGBATo2Half( texture2D( shadow_pass, ( gl_FragCoord.xy + vec2( i, 0.0 ) * radius ) / resolution ) ); mean += distribution.x; squared_mean += distribution.y * distribution.y + distribution.x * distribution.x; #else float depth = unpackRGBAToDepth( texture2D( shadow_pass, ( gl_FragCoord.xy + vec2( 0.0, i ) * radius ) / resolution ) ); mean += depth; squared_mean += depth * depth; #endif } mean = mean * HALF_SAMPLE_RATE; squared_mean = squared_mean * HALF_SAMPLE_RATE; float std_dev = sqrt( squared_mean - mean * mean ); gl_FragColor = pack2HalfToRGBA( vec2( mean, std_dev ) ); } `;