feat: Add support for the number of layers routing (#114)

Author: imrishabh18

bun.lock

@@ -4,6 +4,7 @@ import { processComponentsAndPads } from "./process-components-and-pads"
 import { processNets } from "./process-nets"
 import { processPcbTraces } from "./process-pcb-traces"
 import { processPlatedHoles } from "./process-plated-holes"
+import { generateLayers } from "lib/utils/generate-layers"
 
 export function convertCircuitJsonToDsnJson(
   circuitElements: AnyCircuitElement[],
@@ -18,8 +19,12 @@ export function convertCircuitJsonToDsnJson(
     width: number
     height: number
     center: { x: number; y: number }
+    num_layers?: number
   }
 
+  const numLayers = pcbBoard?.num_layers ?? 2
+  const layers = generateLayers(numLayers)
+
   const pcb: DsnPcb = {
     is_dsn_pcb: true,
     filename: "",
@@ -35,22 +40,7 @@ export function convertCircuitJsonToDsnJson(
     },
     unit: "um",
     structure: {
-      layers: [
-        {
-          name: "F.Cu",
-          type: "signal",
-          property: {
-            index: 0,
-          },
-        },
-        {
-          name: "B.Cu",
-          type: "signal",
-          property: {
-            index: 1,
-          },
-        },
-      ],
+      layers,
       boundary: {
         path: {
           layer: "pcb",

bun.lockb

@@ -0,0 +1,34 @@
+export function generateLayers(numLayers: number) {
+  const layers = []
+
+  // Always add F.Cu as the first layer (index 0)
+  layers.push({
+    name: "F.Cu",
+    type: "signal" as const,
+    property: {
+      index: 0,
+    },
+  })
+
+  // Add inner layers (In1.Cu, In2.Cu, etc.)
+  for (let i = 1; i < numLayers - 1; i++) {
+    layers.push({
+      name: `In${i}.Cu`,
+      type: "signal" as const,
+      property: {
+        index: i,
+      },
+    })
+  }
+
+  // Always add B.Cu as the last layer (index numLayers - 1)
+  layers.push({
+    name: "B.Cu",
+    type: "signal" as const,
+    property: {
+      index: numLayers - 1,
+    },
+  })
+
+  return layers
+}

lib/dsn-pcb/circuit-json-to-dsn-json/convert-circuit-json-to-dsn-json.ts

@@ -0,0 +1,102 @@
+import { expect, test } from "bun:test"
+import { convertCircuitJsonToDsnJson } from "../../lib/dsn-pcb/circuit-json-to-dsn-json/convert-circuit-json-to-dsn-json"
+import type { AnyCircuitElement } from "circuit-json"
+
+test("multi-layer support - 2 layers (default)", () => {
+  const circuitElements: AnyCircuitElement[] = [
+    {
+      type: "pcb_board",
+      pcb_board_id: "pcb_board_0",
+      center: { x: 0, y: 0 },
+      thickness: 1.4,
+      num_layers: 2,
+      width: 34.48,
+      height: 14.16,
+    } as any,
+  ]
+
+  const dsnJson = convertCircuitJsonToDsnJson(circuitElements)
+
+  expect(dsnJson.structure.layers).toHaveLength(2)
+  expect(dsnJson.structure.layers[0].name).toBe("F.Cu")
+  expect(dsnJson.structure.layers[0].property.index).toBe(0)
+  expect(dsnJson.structure.layers[1].name).toBe("B.Cu")
+  expect(dsnJson.structure.layers[1].property.index).toBe(1)
+})
+
+test("multi-layer support - 4 layers", () => {
+  const circuitElements: AnyCircuitElement[] = [
+    {
+      type: "pcb_board",
+      pcb_board_id: "pcb_board_0",
+      center: { x: 0, y: 0 },
+      thickness: 1.4,
+      num_layers: 4,
+      width: 34.48,
+      height: 14.16,
+    } as any,
+  ]
+
+  const dsnJson = convertCircuitJsonToDsnJson(circuitElements)
+
+  expect(dsnJson.structure.layers).toHaveLength(4)
+  expect(dsnJson.structure.layers[0].name).toBe("F.Cu")
+  expect(dsnJson.structure.layers[0].property.index).toBe(0)
+  expect(dsnJson.structure.layers[1].name).toBe("In1.Cu")
+  expect(dsnJson.structure.layers[1].property.index).toBe(1)
+  expect(dsnJson.structure.layers[2].name).toBe("In2.Cu")
+  expect(dsnJson.structure.layers[2].property.index).toBe(2)
+  expect(dsnJson.structure.layers[3].name).toBe("B.Cu")
+  expect(dsnJson.structure.layers[3].property.index).toBe(3)
+})
+
+test("multi-layer support - 6 layers", () => {
+  const circuitElements: AnyCircuitElement[] = [
+    {
+      type: "pcb_board",
+      pcb_board_id: "pcb_board_0",
+      center: { x: 0, y: 0 },
+      thickness: 1.4,
+      num_layers: 6,
+      width: 34.48,
+      height: 14.16,
+    } as any,
+  ]
+
+  const dsnJson = convertCircuitJsonToDsnJson(circuitElements)
+
+  expect(dsnJson.structure.layers).toHaveLength(6)
+  expect(dsnJson.structure.layers[0].name).toBe("F.Cu")
+  expect(dsnJson.structure.layers[0].property.index).toBe(0)
+  expect(dsnJson.structure.layers[1].name).toBe("In1.Cu")
+  expect(dsnJson.structure.layers[1].property.index).toBe(1)
+  expect(dsnJson.structure.layers[2].name).toBe("In2.Cu")
+  expect(dsnJson.structure.layers[2].property.index).toBe(2)
+  expect(dsnJson.structure.layers[3].name).toBe("In3.Cu")
+  expect(dsnJson.structure.layers[3].property.index).toBe(3)
+  expect(dsnJson.structure.layers[4].name).toBe("In4.Cu")
+  expect(dsnJson.structure.layers[4].property.index).toBe(4)
+  expect(dsnJson.structure.layers[5].name).toBe("B.Cu")
+  expect(dsnJson.structure.layers[5].property.index).toBe(5)
+})
+
+test("multi-layer support - no num_layers specified (default to 2)", () => {
+  const circuitElements: AnyCircuitElement[] = [
+    {
+      type: "pcb_board",
+      pcb_board_id: "pcb_board_0",
+      center: { x: 0, y: 0 },
+      thickness: 1.4,
+      width: 34.48,
+      height: 14.16,
+    } as any,
+  ]
+
+  const dsnJson = convertCircuitJsonToDsnJson(circuitElements)
+
+  expect(dsnJson.structure.layers).toHaveLength(2)
+  expect(dsnJson.structure.layers[0].name).toBe("F.Cu")
+  expect(dsnJson.structure.layers[0].property.index).toBe(0)
+  expect(dsnJson.structure.layers[1].name).toBe("B.Cu")
+  expect(dsnJson.structure.layers[1].property.index).toBe(1)
+})