2026-05-07-16-53-23 修正3D模型中心和坐标轴

WebSite/server.ts

@@ -705,22 +705,40 @@ function createStlPreview(filePath: string, fileName: string, limit: number) {
   const step = Math.max(1, Math.ceil(triangleCount / sampleLimit));
   const vertices: number[] = [];
   let sampledTriangles = 0;
+  const bounds = {
+    min: { x: Infinity, y: Infinity, z: Infinity },
+    max: { x: -Infinity, y: -Infinity, z: -Infinity },
+  };
 
-  for (let triangleIndex = 0; triangleIndex < triangleCount; triangleIndex += step) {
+  for (let triangleIndex = 0; triangleIndex < triangleCount; triangleIndex += 1) {
     const offset = 84 + triangleIndex * 50;
     if (offset + 50 > buffer.length) {
       break;
     }
 
+    const shouldSample = triangleIndex % step === 0;
     for (let vertex = 0; vertex < 3; vertex += 1) {
       const vertexOffset = offset + 12 + vertex * 12;
-      vertices.push(
-        Number(buffer.readFloatLE(vertexOffset).toFixed(3)),
-        Number(buffer.readFloatLE(vertexOffset + 4).toFixed(3)),
-        Number(buffer.readFloatLE(vertexOffset + 8).toFixed(3)),
-      );
+      const x = buffer.readFloatLE(vertexOffset);
+      const y = buffer.readFloatLE(vertexOffset + 4);
+      const z = buffer.readFloatLE(vertexOffset + 8);
+      bounds.min.x = Math.min(bounds.min.x, x);
+      bounds.min.y = Math.min(bounds.min.y, y);
+      bounds.min.z = Math.min(bounds.min.z, z);
+      bounds.max.x = Math.max(bounds.max.x, x);
+      bounds.max.y = Math.max(bounds.max.y, y);
+      bounds.max.z = Math.max(bounds.max.z, z);
+      if (shouldSample) {
+        vertices.push(
+          Number(x.toFixed(3)),
+          Number(y.toFixed(3)),
+          Number(z.toFixed(3)),
+        );
+      }
+    }
+    if (shouldSample) {
+      sampledTriangles += 1;
     }
-    sampledTriangles += 1;
   }
 
   const payload = {
@@ -728,6 +746,18 @@ function createStlPreview(filePath: string, fileName: string, limit: number) {
     triangleCount,
     sampledTriangles,
     vertices,
+    bounds: {
+      min: {
+        x: Number(bounds.min.x.toFixed(3)),
+        y: Number(bounds.min.y.toFixed(3)),
+        z: Number(bounds.min.z.toFixed(3)),
+      },
+      max: {
+        x: Number(bounds.max.x.toFixed(3)),
+        y: Number(bounds.max.y.toFixed(3)),
+        z: Number(bounds.max.z.toFixed(3)),
+      },
+    },
   };
   modelPreviewCache.set(cacheKey, payload);
   return payload;