// Section-view clip-volume test. Returns false when `p` (world space) lies
// outside every active box / sphere / cylinder clip region, so the caller
// discards the fragment. Include this after declaring the group-0 binding-6
// `clip_volume: ClipVolumeUB` uniform and the ClipVolumeEntry / ClipVolumeUB
// structs, which every clipping shader already carries.
fn clip_volume_test(p: vec3<f32>) -> bool {
for (var i = 0u; i < clip_volume.count; i = i + 1u) {
let e = clip_volume.volumes[i];
if e.volume_type == 2u {
let d = p - e.center;
let local = vec3<f32>(dot(d, e.col0), dot(d, e.col1), dot(d, e.col2));
if abs(local.x) > e.half_extents.x
|| abs(local.y) > e.half_extents.y
|| abs(local.z) > e.half_extents.z {
return false;
}
} else if e.volume_type == 3u {
let ds = p - e.center;
if dot(ds, ds) > e.radius * e.radius { return false; }
} else if e.volume_type == 4u {
let axis = e.col0;
let d = p - e.center;
let along = dot(d, axis);
if abs(along) > e.half_extents.x { return false; }
let radial = d - axis * along;
if dot(radial, radial) > e.radius * e.radius { return false; }
}
}
return true;
}