Surface shader modifier: grid effect

grid-surface-shader.metal

float u = _surface.diffuseTexcoord.x;
float v = _surface.diffuseTexcoord.y;
int u100 = int(u * 100.0);
int v100 = int(v * 100.0);

if (u100 % 2 == 1 || v100 % 2 == 1) { 
    // do nothing
} else {
    discard_fragment();
}