patch (#154)

Author: Abse2001

lib/utils/coordinate-transform.ts

@@ -106,9 +106,9 @@ export const COORDINATE_TRANSFORMS = {
     axisMapping: { x: "x", y: "z", z: "-y" },
   } as CoordinateTransformConfig,
 
-  // For step models, the models are being loaded inverted
+  // STEP models need Y/Z remap without the extra 180-degree board-direction flip.
   STEP_INVERTED: {
-    axisMapping: { x: "-x", y: "z", z: "-y" },
+    axisMapping: { x: "x", y: "z", z: "y" },
   } as CoordinateTransformConfig,
 
   // USB port fix: flip to top of board (flip Y axis after Z-up conversion)

tests/features/translucent-glb-models/__snapshots__/translucent-cadmodel-standalone.snap.png

@@ -15,7 +15,6 @@ test("translucent-cadmodel-standalone", async () => {
           <cadassembly>
             <cadmodel
               modelUrl="https://modelcdn.tscircuit.com/jscad_models/soic8.step"
-              rotationOffset={{ x: 0, y: 0, z: 180 }}
               showAsTranslucentModel
             />
           </cadassembly>

tests/features/translucent-glb-models/translucent-cadmodel.test.tsx

@@ -13,10 +13,7 @@ test("STEP CAD Model should be included in GLTF output", async () => {
         footprint="soic8"
         cadModel={
           <cadassembly>
-            <cadmodel
-              modelUrl="https://modelcdn.tscircuit.com/jscad_models/soic8.step"
-              rotationOffset={{ x: 0, y: 0, z: 180 }}
-            />
+            <cadmodel modelUrl="https://modelcdn.tscircuit.com/jscad_models/soic8.step" />
           </cadassembly>
         }
       />
@@ -43,4 +40,4 @@ test("STEP CAD Model should be included in GLTF output", async () => {
   expect(
     renderGLTFToPNGBufferFromGLBBuffer(glb as ArrayBuffer, cameraOptions),
   ).toMatchPngSnapshot(import.meta.path)
-})
+}, 20000)

tests/repro/repro6.test.tsx

@@ -0,0 +1,14 @@
+import { expect, test } from "bun:test"
+import {
+  COORDINATE_TRANSFORMS,
+  applyCoordinateTransform,
+} from "../../lib/utils/coordinate-transform"
+
+test("STEP transform preserves board direction while remapping STEP axes", () => {
+  expect(
+    applyCoordinateTransform(
+      { x: 1, y: 2, z: 3 },
+      COORDINATE_TRANSFORMS.STEP_INVERTED,
+    ),
+  ).toEqual({ x: 1, y: 3, z: 2 })
+})