Handle connected copper in fanout clearance

README.md

@@ -57,6 +57,8 @@ and treats each bus-layer decision atomically.
 - Chamfers orthogonal routing corners into 45° segments before validating and
   emitting the fanout.
 - Verifies pad, via, trace, and already-routed fanout clearance.
+- Treats an obstacle whose `connectedTo` list contains the connection name as
+  electrically connected copper rather than a foreign keepout.
 - Emits supplied fanout traces, via obstacles, and moved breakout endpoints in a
   new `SimpleRouteJson`. The returned problem is ready for a downstream
   autorouter to finish.
@@ -296,6 +298,22 @@ and clearance values as the JLCPCB regressions.
 | ----------- | ------------ | ----: | -----------------: | ---------------: | -----: |
 | `sample001` | FCBGA1088L   |  1088 |                589 |              499 |      6 |
 
+## Dataset 06
+
+`datasets/dataset06.ts` preserves the exact 132-connection, 265-obstacle,
+single-layer mixed-footprint input from the clad1 RP2040 board. The checked-in
+snapshot is intentionally labeled with its routed count:
+
+![clad1 RP2040 fanout reproduction](docs/images/dataset06/sample001.png)
+
+Same-connection copper awareness improves the deterministic result from 35 to
+37 routed connections. The remaining repro is not presented as solved: it
+contains escapes that must first move away from their requested boundary before
+turning around the RP2040 pad field and large exposed pad. Completing it
+requires a non-monotone single-layer search. Treating repeated terminals of one
+electrical net as a mergeable multi-terminal tree would also remove artificial
+same-net congestion.
+
 ## Development
 
 ```sh
@@ -312,7 +330,10 @@ connection, routing, and layer-assignment metrics. `bun run start` opens the
 datasets in the standard tscircuit solver debugger. `bun run
 render:dataset` writes `graphics-debug` PNGs under one subdirectory per dataset,
 with a red shared boundary, gray component courtyards, and green fanout-exit
-markers.
+markers. Pass an output directory and dataset id to render one dataset, for
+example `bun scripts/render-dataset-pngs.ts docs/images dataset06`. Failed
+regressions render their best partial attempt with a visible `INCOMPLETE`
+label.
 
 ## Scope
 

datasets/dataset06.ts

@@ -20,7 +20,7 @@ export const fanoutDataset06: FanoutDatasetSample[] = [
     id: "sample001",
     name: "clad1 RP2040 shared-boundary reproduction",
     description:
-      "Exact serialized single-layer fanout input from the clad1 RP2040 assembly. The current solver routes 35 of 132 connections through the shared component-area boundary.",
+      "Exact serialized single-layer fanout input from the clad1 RP2040 assembly. Same-connection copper awareness raises the partial route from 35 to 37 of 132 connections; completing the fixture still requires non-monotone escapes and electrically connected multi-terminal merging.",
     footprintCount: componentIds.size,
     footprinterStrings: ["clad1 RP2040 assembly (serialized SRJ)"],
     simpleRouteJson: fixture.simpleRouteJson,

lib/route-bus.ts

@@ -646,6 +646,7 @@ function segmentIsClearOfObstacles(params: {
   const { segment, plan, segmentIndex, obstacles, clearance } = params
   for (const obstacle of obstacles) {
     if (!obstacle.layers.includes(segment.layer)) continue
+    if (obstacle.connectedTo.includes(plan.connectionName)) continue
     if (
       segmentIndex === 0 &&
       obstacle === plan.sourceObstacle &&

scripts/render-dataset-pngs.ts

@@ -31,6 +31,7 @@ function createVerificationOverlay(
   srj: SimpleRouteJson,
   componentBounds: ComponentBounds[],
   sharedBoundary: Bounds,
+  statusLabel?: string,
 ): GraphicsObject {
   return {
     rects: [
@@ -55,6 +56,21 @@ function createVerificationOverlay(
         fill: "#ef444408",
         stroke: "#dc2626",
       },
+      ...(statusLabel
+        ? [
+            {
+              center: {
+                x: (sharedBoundary.minX + sharedBoundary.maxX) / 2,
+                y: sharedBoundary.maxY + 0.65,
+              },
+              width: 20,
+              height: 0.8,
+              fill: "#ffffff",
+              stroke: "#dc2626",
+              label: statusLabel,
+            },
+          ]
+        : []),
     ],
     points: srj.connections.flatMap((connection) =>
       connection.pointsToConnect.flatMap((point) =>
@@ -96,9 +112,12 @@ function formatFootprinterStrings(strings: string[]): string {
 }
 
 const outputDirectory = process.argv[2] ?? "verification-pngs"
+const requestedDatasetId = process.argv[3]
 await mkdir(outputDirectory, { recursive: true })
 
-for (const dataset of fanoutDatasets) {
+for (const dataset of fanoutDatasets.filter(
+  (candidate) => !requestedDatasetId || candidate.id === requestedDatasetId,
+)) {
   const datasetDirectory = `${outputDirectory}/${dataset.id}`
   await mkdir(datasetDirectory, { recursive: true })
 
@@ -108,23 +127,26 @@ for (const dataset of fanoutDatasets) {
       sample.solverOptions,
     )
     solver.solve()
-    if (solver.failed) {
-      throw new Error(
-        `${dataset.id}/${sample.id} failed: ${solver.error ?? "unknown solver error"}`,
-      )
-    }
 
-    const output = solver.getOutput()
+    const visualizedSrj = solver.solved
+      ? solver.getOutput().simpleRouteJson
+      : sample.simpleRouteJson
     const componentBounds = getComponentBounds(sample.componentBounds)
+    const routeStatus = solver.failed
+      ? ` · incomplete: ${solver.attempts[0]?.routedConnectionCount ?? 0}/${sample.simpleRouteJson.connections.length}`
+      : ""
     const graphics = mergeGraphics(
       {
         ...solver.visualize(),
-        title: `${dataset.id}/${sample.id}: ${sample.name} · ${formatFootprinterStrings(sample.footprinterStrings)}`,
+        title: `${dataset.id}/${sample.id}: ${sample.name} · ${formatFootprinterStrings(sample.footprinterStrings)}${routeStatus}`,
       },
       createVerificationOverlay(
-        output.simpleRouteJson,
+        visualizedSrj,
         componentBounds,
         sample.sharedBoundary,
+        solver.failed
+          ? `INCOMPLETE ${solver.attempts[0]?.routedConnectionCount ?? 0}/${sample.simpleRouteJson.connections.length}`
+          : undefined,
       ),
     )
     const png = await getPngBufferFromGraphicsObject(graphics, {
@@ -135,7 +157,7 @@ for (const dataset of fanoutDatasets) {
       pngWidth: 1400,
       viewbox: getVerificationViewbox(
         sample.sharedBoundary,
-        output.simpleRouteJson.bounds,
+        visualizedSrj.bounds,
       ),
     })
     const outputPath = `${datasetDirectory}/${sample.id}.png`

tests/connected-copper-obstacles.test.ts

@@ -0,0 +1,78 @@
+import { expect, test } from "bun:test"
+import type { SimpleRouteJson } from "@tscircuit/capacity-autorouter"
+import { FanoutSolver } from "lib/fanout-solver"
+import type { FanoutBusSpec } from "lib/types"
+
+test("a fanout trace may cross copper connected to the same connection", () => {
+  const simpleRouteJson: SimpleRouteJson = {
+    layerCount: 1,
+    minTraceWidth: 0.1,
+    nominalTraceWidth: 0.1,
+    minViaPadDiameter: 0.25,
+    minViaHoleDiameter: 0.15,
+    minTraceToPadEdgeClearance: 0.1,
+    minViaEdgeToPadEdgeClearance: 0.1,
+    defaultObstacleMargin: 0.1,
+    bounds: { minX: -1, maxX: 4, minY: -0.3, maxY: 0.3 },
+    obstacles: [
+      {
+        obstacleId: "source-pad",
+        componentId: "source-component",
+        type: "rect",
+        center: { x: 0, y: 0 },
+        width: 0.2,
+        height: 0.2,
+        layers: ["top"],
+        connectedTo: ["SIGNAL", "source-pad"],
+      },
+      {
+        obstacleId: "connected-copper",
+        componentId: "connected-component",
+        type: "rect",
+        center: { x: 1, y: 0 },
+        width: 0.8,
+        height: 0.4,
+        layers: ["top"],
+        connectedTo: ["SIGNAL"],
+      },
+    ],
+    connections: [
+      {
+        name: "SIGNAL",
+        pointsToConnect: [
+          {
+            x: 0,
+            y: 0,
+            layer: "top",
+            pointId: "source-pad",
+            pcb_port_id: "source-pad",
+          },
+          { x: 4, y: 0, layer: "top" },
+        ],
+      },
+    ],
+    buses: [
+      {
+        busId: "signal-bus",
+        connectionNames: ["SIGNAL"],
+        sourceComponentId: "source-component",
+        direction: "right",
+      },
+    ] as FanoutBusSpec[],
+  }
+
+  const solver = new FanoutSolver(simpleRouteJson, {
+    sharedBoundary: { minX: -0.5, maxX: 3, minY: -0.3, maxY: 0.3 },
+    escapeLayers: ["top"],
+  })
+  solver.solve()
+
+  expect(solver.failed).toBe(false)
+  expect(solver.getOutput().fanoutTraces).toHaveLength(1)
+  expect(solver.getOutput().fanoutTraces[0]!.route.at(-1)).toMatchObject({
+    route_type: "wire",
+    x: 3,
+    y: 0,
+    layer: "top",
+  })
+})

tests/dataset06-clad1-rp2040-repro.test.ts

@@ -2,7 +2,7 @@ import { expect, test } from "bun:test"
 import { FanoutSolver } from "lib/fanout-solver"
 import { fanoutDataset06 } from "../datasets/dataset06"
 
-test("dataset06 reproduces the incomplete clad1 RP2040 shared-boundary fanout", () => {
+test("dataset06 records the remaining clad1 RP2040 fanout gap", () => {
   const sample = fanoutDataset06[0]!
 
   expect(sample.simpleRouteJson.layerCount).toBe(1)
@@ -22,11 +22,11 @@ test("dataset06 reproduces the incomplete clad1 RP2040 shared-boundary fanout",
 
   expect(solver.failed).toBe(true)
   expect(solver.error).toBe(
-    "FanoutSolver: best layer assignment routed 35/132 connections",
+    "FanoutSolver: best layer assignment routed 37/132 connections",
   )
   expect(solver.attempts).toHaveLength(1)
   expect(solver.attempts[0]).toMatchObject({
-    routedConnectionCount: 35,
-    routedBusCount: 35,
+    routedConnectionCount: 37,
+    routedBusCount: 37,
   })
-}, 20_000)
+}, 60_000)