核心隐私保证：100% 客户端处理

在 Online Free Protractor（可通过 onlinefreeprotractor.com 访问），您的隐私是我们的首要任务。我们的整个应用程序通过标准 HTML5 Canvas、WebRTC 和 DeviceOrientation API 在您的 Web 浏览器中本地运行。我们不会在任何外部服务器上传输、记录或存储您的照片、蓝图、相机视频流或陀螺仪传感器数据。

1. 我们不收集的信息

上传的图像和蓝图：当您上传照片或粘贴屏幕截图 (Ctrl+V) 时，文件会直接加载到浏览器本地 RAM 内存中。任何图像数据都不会传输到云服务器。
实时相机反馈：相机 AR 功能仅激活您的设备视频传感器，以在虚拟量角器后面显示实时预览。我们绝不会录制、快照或流式传输您的视频。
运动和指南针传感器数据：实时处理加速度计、陀螺仪和磁力计遥测（俯仰、滚动和方位角轴承），纯粹用于虚拟指针和量角器对准。
个人身份信息 (PII)：我们不需要帐户注册、密码、姓名、实际地址或电话号码即可使用任何工具。

2. 本地存储和首选项

我们仅使用现代浏览器 localStorage 来记住您在访问时首选的客户端设置：

主题偏好：深色模式或浅色模式主题选择。
设备预设：您最后选择的用于 1:1 比例校准的屏幕 PPI 配置文件。
单位首选项：您选择的线性比例单位（厘米、毫米、英寸、像素）。

3. Google AdSense & Third-Party Advertising Cookies

We use Google AdSense (Google LLC) to serve advertisements when you visit our website. To keep all geometry tools 100% free and accessible without paywalls, advertising partners may place or read cookies on your browser.

Google DoubleClick DART Cookie: Third-party vendors, including Google, use cookies to serve ads based on a user's prior visits to Online Free Protractor or other websites on the Internet. Google's use of advertising cookies enables it and its partners to serve ads to our users based on their visit to our site and/or other sites on the Internet.
Personalized vs. Non-Personalized Ads: Depending on your region and cookie consent preferences, ads displayed may be tailored to your interests or served non-personalized based purely on page context.

How to Opt Out: Users may opt out of personalized advertising at any time by visiting Google Ads Settings. Alternatively, you can opt out of a third-party vendor's use of cookies for personalized advertising by visiting aboutads.info choices.

4. Google Analytics (GA4)

We use Google Analytics 4 (Measurement ID: G-8C68J6SL24) to monitor aggregated traffic patterns, country-level visitor counts, and system performance metrics. Google Analytics does not log or store individual IP addresses and operates with strict anonymization to protect user privacy.

5. European (GDPR) & California (CCPA) Privacy Rights

Under the General Data Protection Regulation (GDPR) for EEA/UK residents and the California Consumer Privacy Act (CCPA), you are entitled to specific rights:

Right to Opt-Out: We do not sell or share personal data. You have the right to decline non-essential cookies at any time.
Right to Access & Erasure: Because we do not create accounts or store user images/files on servers, we hold no user data to access or delete.
Right to Non-Discrimination: All interactive tools remain 100% free and functional regardless of your privacy choices.

6. Contact & Inquiries

If you have questions regarding this Privacy Policy, cookie handling, or website operations, please contact our engineering team via our 联系与反馈.