Tiled patterns on images

        vector bb = relbbox(0, v@P);
vector2 uv = set(bb.x, bb.y);
vector clr = colormap(image, uv);
float lum = luminance(clr);

uv.y += sin(bb.x * PI * w) * a;
vector2 tile = frac(uv * f);
float mask = dot(tile, tile);

v@C = mask < lum;
    

        string map = chs('map');
int freq = chi('frequency');
float r_min = chf('min_radius');
float r_max = chf('max_radius');

vector bb = relbbox(0, v@P);
vector2 uv = set(bb.x, bb.y);
vector2 raster = floor(uv * freq) * (1.0 / freq);

vector clr = colormap(map, raster);
float lum = fit01(luminance(clr), r_min, r_max);

vector tile = frac(uv * freq) - {0.5, 0.5};
float r = length(tile) * 2.0;
float mask = smooth(r - 0.05, r, lum);

v@C = clr * mask;