Level sets & topology
How a smooth field becomes a solid surface — and the choice between a sheet, a solid, and a half-solid.
A surface where the field equals a value.
Many F13LD tools build geometry from a scalar field φ(x, y, z) — a number at every point in space. A level set is the surface where that field equals a chosen iso value; sweeping the iso value moves the surface and changes how much volume it encloses.
Topology is the choice of which part becomes solid. A solid keeps everything on one side of the surface. A sheet keeps a constant-thickness shell straddling it, giving a thin-walled structure. A half-solid keeps one network and leaves the complementary channel open.
Two controls, very different results.
tpms, wave, grain, and noise all expose this directly: an iso (or center / half-width) control sets the level, and a topology control switches between sheet, solid, and half-solid. The same field yields a delicate shell or a dense solid depending only on these two settings.
Match the topology to the job.
Reach for a sheet when you want low density and high surface area, a solid for maximum stiffness, and a half-solid when you need one connected open channel for flow or infiltration.