feat: add local access control and managed point clouds

server/pointcloudSample.test.ts

@@ -0,0 +1,60 @@
+import { mkdtempSync, rmSync, writeFileSync } from 'node:fs';
+import { tmpdir } from 'node:os';
+import { join } from 'node:path';
+import { afterEach, describe, expect, it } from 'vitest';
+import { samplePointcloudFile } from './pointcloudSample';
+
+const temporaryDirectories: string[] = [];
+
+afterEach(() => {
+  while (temporaryDirectories.length > 0) {
+    rmSync(temporaryDirectories.pop()!, { recursive: true, force: true });
+  }
+});
+
+function writeBinaryPly(properties: string[], records: number[][]): string {
+  const directory = mkdtempSync(join(tmpdir(), 'pointcloud-sample-'));
+  temporaryDirectories.push(directory);
+  const filePath = join(directory, 'cloud.ply');
+  const header = Buffer.from([
+    'ply',
+    'format binary_little_endian 1.0',
+    `element vertex ${records.length}`,
+    ...properties.map((name) => `property float ${name}`),
+    'end_header',
+    '',
+  ].join('\n'), 'ascii');
+  const body = Buffer.alloc(records.length * properties.length * 4);
+  records.forEach((record, recordIndex) => {
+    record.forEach((value, propertyIndex) => {
+      body.writeFloatLE(value, (recordIndex * properties.length + propertyIndex) * 4);
+    });
+  });
+  writeFileSync(filePath, Buffer.concat([header, body]));
+  return filePath;
+}
+
+describe('samplePointcloudFile', () => {
+  it('不会为只有 xyz 的输入点云伪造误差', async () => {
+    const filePath = writeBinaryPly(
+      ['x', 'y', 'z'],
+      [[1, 2, 3], [4, 5, 6]],
+    );
+
+    const points = await samplePointcloudFile(filePath, 1_000, 2);
+
+    expect(points).toHaveLength(2);
+    expect(points.every((point) => point.error === undefined)).toBe(true);
+  });
+
+  it.each(['error', 'deviation'])('保留 PLY 中真实的 %s 属性', async (errorProperty) => {
+    const filePath = writeBinaryPly(
+      ['x', 'y', 'z', errorProperty],
+      [[1, 2, 3, 0.25], [4, 5, 6, -0.5]],
+    );
+
+    const points = await samplePointcloudFile(filePath, 1_000, 2);
+
+    expect(points.map((point) => point.error)).toEqual([0.25, -0.5]);
+  });
+});