     float phi = M_2PI / n;
     float gamma = (floor(a / phi) + 0.5) * phi - a;
     float d = cos(gamma) * length(pos);
-    return 1.0 - smoothstep(size - smth, size + smth, d);
+    return smoothstep(size - smth, size + smth, d);
 }
 
 

    vec3 p = abs(fract(c.xxx + K.xyz) * 6.0 - K.www);
    return c.z * mix(K.xxx, clamp(p - K.xxx, 0.0, 1.0), c.y);
}

float rectReg(vec2 ul, vec2 dim, vec2 pos)
{
