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Fabrication overrides

Most of what decides a feature’s shape does not sit on the feature. A channel’s depth comes from the layer it is drawn on; a corner’s radius comes from the process forming that layer. An override is where you say otherwise for one child, and one grammar covers every such row.

The grammar

Every override row carries a checkbox.

Unticked, the value is inherited, and the effective value is shown dimmed beside the name of where it came from. Ticked, the value is this child’s own.

Ticking seeds the override from whatever the row is displaying, so ticking alone never moves any geometry — you tick, then edit. Unticking clears the override and returns the row to tracking what it inherits, which is why an inherited value follows a later change to the layer or the process instead of going stale the way a copy would.

A child sitting off the stack has no layer to inherit from. Its unset rows read — and cannot be ticked; overrides already on it stay editable and removable.

Which children carry them

Void compartments, channels and points carry a fabrication group. A material compartment carries none — untouched slab has no face, no depth and no walls to state.

Face, depth and walls

These three inherit from the layer.

Face picks which side of the slab the feature is formed from. It appears only at the child itself, since every part of one child opens from one side.

Depth is in micrometres, measured in from that face. It is what makes a chamber deeper than the channels running into it, or a pocket a step in that chamber’s floor.

Walls is the wall profile: Vertical, Fillet with a radius, or Draft with an angle in degrees. The kind and its parameter are overridden independently, and the parameter row appears only when the profile has one to set. Leaving the parameter unset means the process’s forming default, live — so it follows a process edit rather than freezing at the number that was there when you chose the kind.

A wall kind the layer’s process cannot form is not refused. The geometry builds and the Problems list reports it.

Corner radii

A drawn corner is infinitely sharp and no instrument is, so every in-plane corner is formed at some radius. Radii come in two classes: inner, at a corner of the void, and outer, at a corner of the material. Which class a corner takes follows from its own shape — the outside of a bend is one, the inside is the other — so you never pick a class, you set the pair.

Corner radii inherit from the process, not from the layer, because a layer already names the process that forms it. Under that base sit two authored tiers:

  • the element tier — a channel, a region or a point;
  • the vertex tier — a channel’s interior station or a region’s ring vertex, overriding its element’s.

The two arms are independent. Override the inner radius and the outer goes on tracking the process.

A region ring vertex is exactly one corner, so it authors one radius rather than a pair, and its row names the class that corner takes there. Drag the vertex from convex to reflex and the value follows it into the other class. A channel station and a point each induce corners of both classes, so each authors the pair.

A channel end carries no corner rows of its own: its corners belong to the point it connects to, so a junction’s corners are authored once rather than once on every channel arriving there.

See also