refactor: move centering to 3mf gen

src/components/md-token-viewer.tsx

@@ -51,14 +51,6 @@ export default function MdTokenViewer(props: TokenViewerProps) {
 
       // 3MF 文件可能返回一个 Group，包含多个 Mesh
       group = object instanceof THREE.Group ? object : new THREE.Group().add(object);
-
-      // 计算边界框并居中
-      const box = new THREE.Box3().setFromObject(group);
-      const center = box.getCenter(new THREE.Vector3());
-      group.position.x = -center.x;
-      group.position.y = -center.y;
-      group.position.z = -center.z;
-
       group.rotateX(Math.PI);
 
       // 为每个 mesh 启用原始颜色

src/components/utils/3mf-generator.ts

@@ -1,6 +1,7 @@
 import * as THREE from "three";
 import { exportTo3MF } from "three-3mf-exporter";
 import type { TraceResult } from "./image-tracer";
+import {Vector3} from "three";
 
 export interface ExtrusionSettings {
   size: number; // 模型整体尺寸 (mm)
@@ -53,6 +54,7 @@ export async function generate3MF(
   const meshes: LayerMesh[] = [];
   let layerIndex = 0;
 
+  let boundingBox = new THREE.Box3();
   for (const layerSetting of settings.layers) {
     const layer = traceResult.layers.find((l) => l.id === layerSetting.id);
     if (!layer) continue;
@@ -61,9 +63,11 @@ export async function generate3MF(
     const extrudeSettings: THREE.ExtrudeGeometryOptions = {
       depth: layerSetting.thickness,
       curveSegments: 36,
-      bevelEnabled: false,
+      bevelEnabled: true,
+      bevelSize: 0.4
     };
     const geometry: THREE.ExtrudeGeometry = new THREE.ExtrudeGeometry(layer.paths, extrudeSettings);
+    geometry.computeBoundingBox();
 
     // 为该图层生成颜色
     const color = generateLayerColor(layerIndex);
@@ -74,6 +78,7 @@ export async function generate3MF(
     });
 
     const mesh = new THREE.Mesh(geometry, material);
+    boundingBox.expandByObject(mesh);
 
     // 设置图层高度（堆叠）
     mesh.position.y = currentHeight;
@@ -90,6 +95,11 @@ export async function generate3MF(
     layerIndex++;
   }
 
+  const center = boundingBox.getCenter(new Vector3());
+  for(const mesh of meshes){
+      mesh.mesh.position.sub(center);
+  }
+
   if (meshes.length === 0) {
     throw new Error("没有可生成的图层");
   }