Fix Automatic Model Origin (#146)

* commit repros

* fix model origin realignment

* fix types

Author: seveibar

lib/utils/cad-mesh-placement.ts

@@ -77,18 +77,7 @@ export function getMeshOrigin(
     return origin
   }
 
-  switch (cad.model_origin_alignment) {
-    case "center":
-      return getBoundingBoxCenter(meshBounds)
-    case "center_of_component_on_board_surface":
-      return {
-        x: (meshBounds.min.x + meshBounds.max.x) / 2,
-        y: meshBounds.min.y,
-        z: (meshBounds.min.z + meshBounds.max.z) / 2,
-      }
-    default:
-      return null
-  }
+  return { x: 0, y: 0, z: 0 }
 }
 
 export function fitMeshToCadBounds<T extends STLMesh | OBJMesh>(

package.json

@@ -30,7 +30,7 @@
     "@resvg/resvg-js": "^2.6.2",
     "@resvg/resvg-wasm": "^2.6.2",
     "@tscircuit/alphabet": "^0.0.8",
-    "@tscircuit/circuit-json-util": "^0.0.72",
+    "@tscircuit/circuit-json-util": "^0.0.90",
     "@types/bun": "latest",
     "@types/earcut": "^3.0.0",
     "@types/react": "^19.1.9",
@@ -46,7 +46,7 @@
     "react-cosmos": "^7.0.0",
     "react-cosmos-plugin-vite": "^7.0.0",
     "react-dom": "^19.1.1",
-    "tscircuit": "^0.0.1328",
+    "tscircuit": "^0.0.1520",
     "tsup": "^8.5.0",
     "vite": "^7.1.1"
   },

tests/repro/__snapshots__/repro7.snap.png

@@ -10,7 +10,7 @@ test("repro7: local CAD model should be included in GLTF output", async () => {
     <board width="40mm" height="40mm">
       <chip
         name="U1"
-        footprint="soic8"
+        footprint="pinrow1"
         cadModel={
           <cadassembly>
             <cadmodel modelUrl="tests/assets/ExampleModelPin.step" />

tests/repro/__snapshots__/repro8.snap.png

@@ -0,0 +1,45 @@
+import { expect, test } from "bun:test"
+import { getMeshOrigin } from "../../lib/utils/cad-mesh-placement"
+
+test("getMeshOrigin ignores inferred alignment without explicit origin position", () => {
+  const origin = getMeshOrigin(
+    {
+      type: "cad_component",
+      cad_component_id: "cad1",
+      pcb_component_id: "pcb1",
+      source_component_id: "source1",
+      position: { x: 0, y: 0, z: 0 },
+      model_object_fit: "contain_within_bounds",
+      anchor_alignment: "center",
+      model_origin_alignment: "center_of_component_on_board_surface",
+    },
+    {
+      min: { x: -2, y: -3, z: -4 },
+      max: { x: 6, y: 7, z: 8 },
+    },
+  )
+
+  expect(origin).toEqual({ x: 0, y: 0, z: 0 })
+})
+
+test("getMeshOrigin returns explicit model origin position", () => {
+  const origin = getMeshOrigin(
+    {
+      type: "cad_component",
+      cad_component_id: "cad1",
+      pcb_component_id: "pcb1",
+      source_component_id: "source1",
+      position: { x: 0, y: 0, z: 0 },
+      model_object_fit: "contain_within_bounds",
+      anchor_alignment: "center",
+      model_origin_alignment: "center_of_component_on_board_surface",
+      model_origin_position: { x: 1, y: 2, z: 3 },
+    },
+    {
+      min: { x: -2, y: -3, z: -4 },
+      max: { x: 6, y: 7, z: 8 },
+    },
+  )
+
+  expect(origin).toEqual({ x: 1, y: 2, z: 3 })
+})