@tscircuit/capacity-autorouter
An MIT-licensed full-pipeline PCB autorouter library for node.js and TypeScript projects. Part of tscircuit
View Online Playground · tscircuit docs · discord · twitter · try tscircuit online · Report/Debug Autorouter Bugs
Want to understand how the autorouter works? Check out a stage-by-stage breakdown with videos in this autorouter walk through
How to file a bug report
- You should have created a bug report via the tscircuit errors tab
- Run
bun run bug-report <bug-report-url>to download the report and create a debugging fixture file in theexamples/bug-reportsdirectory, you can then find the bug report in the server (viabun run start) - Or run
bun run bug-report-with-test <bug-report-url>to download the report, create the fixture, and scaffold a matching snapshot test undertests/bugs
Installation
bun add @tscircuit/capacity-autorouter
Usage as a Library
Basic Usage
import { CapacityMeshSolver } from "@tscircuit/capacity-autorouter"
// Create a solver with SimpleRouteJson input
const solver = new CapacityMeshSolver(simpleRouteJson)
// Run the solver until completion
while (!solver.solved && !solver.failed) {
solver.step()
}
// Check if solving was successful
if (solver.failed) {
console.error("Routing failed:", solver.error)
} else {
// Get the routing results as SimpleRouteJson with traces
const resultWithRoutes = solver.getOutputSimpleRouteJson()
// Use the resulting routes in your application
console.log(
`Successfully routed ${resultWithRoutes.traces?.length} connections`
)
}
Input Format: SimpleRouteJson
The input to the autorouter is a SimpleRouteJson object with the following structure:
interface SimpleRouteJson {
layerCount: number
minTraceWidth: number
obstacles: Obstacle[]
connections: Array<SimpleRouteConnection>
bounds: { minX: number; maxX: number; minY: number; maxY: number }
traces?: SimplifiedPcbTraces // Optional for input
}
interface Obstacle {
type: "rect"
layers: string[]
center: { x: number; y: number }
width: number
height: number
connectedTo: string[] // TraceIds
offBoardConnectsTo?: string[] // TraceIds connected off-board
}
interface SimpleRouteConnection {
name: string
pointsToConnect: Array<{ x: number; y: number; layer: string }>
}
Output Format
The getOutputSimpleRouteJson() method returns the original SimpleRouteJson with a populated traces property. The traces are represented as SimplifiedPcbTraces:
type SimplifiedPcbTraces = Array<{
type: "pcb_trace"
pcb_trace_id: string // TraceId
route: Array<
| {
route_type: "wire"
x: number
y: number
width: number
layer: string
}
| {
route_type: "via"
x: number
y: number
to_layer: string
from_layer: string
}
>
}>
Advanced Configuration
You can provide optional configuration parameters to the solver:
const solver = new CapacityMeshSolver(simpleRouteJson, {
// Optional: Manually set capacity planning depth (otherwise automatically calculated)
capacityDepth: 7,
// Optional: Set the target minimum capacity for automatic depth calculation
// Lower values result in finer subdivisions (higher depth)
targetMinCapacity: 0.5,
})
By default, the solver will automatically calculate the optimal capacityDepth to achieve a target minimum capacity of 0.5 based on the board dimensions. This automatic calculation ensures that the smallest subdivision cells have an appropriate capacity for routing.
Visualization Support
For debugging or interactive applications, you can use the visualize() method to get a visualization of the current routing state:
// Get visualization data that can be rendered with graphics-debug
const visualization = solver.visualize()
Development
To work on this library:
# Install dependencies
bun install
# Start the interactive development environment
bun run start
# Run tests
bun test
# Build the library
bun run build