# ! Rushabh | Linux Shill - A real example is in ...

Channel: #contributor
Source: https://discord.com/channels/1233487248129921135/1554195154871779430
Started: 2026-09-28T18:16:40.904000+00:00
Last activity: 2026-09-28T22:04:20.722000+00:00

## ! Rushabh | Linux Shill — 2026-09-28T18:16:40.471000+00:00

A real example is in TI’s TMDS62LEVM board. Its Altium PCB file contains a full-circle keepout with a 103 mil centerline radius and 1 mil stroke width
## Proposal: native annular PCB keepout

Add `shape: "annulus"` to Circuit JSON’s [`pcb_keepout` schema](https://github.com/tscircuit/circuit-json/blob/main/src/pcb/pcb_keepout.ts):

```ts
{
  type: "pcb_keepout",
  shape: "annulus",
  pcb_keepout_id: "keepout_1",
  center: { x: 10, y: 20 },
  inner_radius: 1.5,
  outer_radius: 2.5,
  layers: ["top"]
}
```

The keepout occupies the ring between the two radii; **the center remains usable**. Require `0 < inner_radius < outer_radius` and retain the existing keepout permissions and metadata fields. Circuit JSON already has an `outline` shape, but an annulus would represent this geometry exactly in one element.

Implementation would add schema and type tests in `circuit-json`, then update SVG rendering and keepout intersection checks. This converter could replace hundreds of approximate circles with one annulus per Altium full-circle arc: `inner_radius = radius − width / 2` and `outer_radius = radius + width / 2`. It should continue emitting a filled circle when the inner radius is zero or negative.

## ! Rushabh | Linux Shill — 2026-09-28T18:16:53.350000+00:00

<@757706909351411845>

## ! Rushabh | Linux Shill — 2026-09-28T18:21:32.651000+00:00

<@809856037376491570>

## Seve — 2026-09-28T18:22:19.394000+00:00

you can just use a polygon i think, annulus is a bit weird, i would say "ring"

## ! Rushabh | Linux Shill — 2026-09-28T21:00:10.632000+00:00

https://github.com/tscircuit/circuit-json/pull/840/

## Seve — 2026-09-28T22:04:20.722000+00:00

you should use brep polygons for now