Merge Meshes on Import

Questions
3

Thanks for such a prompt reply. So I tried mergeBufferGeometries() as follows but all of the items appear in the same location. Performance doesn’t seen great either. I must be missing something obvious:

    // Get the objects.
    const importedObjects: THREE.Object3D = scene.getObjectByName("Part_Group");

    // Check we have found the Objects.
    if (importedObjects !== null) {

      // Create an empty Object to hold the Geometry.
      const geometryArray = [];

      // Create a material.
      const objectMaterial = new THREE.MeshLambertMaterial({ color: 0xffff00, side: THREE.DoubleSide })

      // Iterate through the children
      importedObjects.children.forEach(child => {

        if (child instanceof THREE.Mesh) {

          geometryArray.push(child.geometry);

        }

      });

      let mergedGeom = new THREE.BufferGeometry();
      mergedGeom = BufferGeometryUtils.mergeBufferGeometries(geometryArray);

      // Create an object3D from the tundishes Geometry.
      const mergedMesh = new THREE.Mesh(mergedGeom, objectMaterial);

      // Add the tundishes to the scene.
      this.sceneMaster.add(mergedMesh);