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Magnetometer + accelerometer → Kalman filter → pitch/roll compensated heading.
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Gyroscope drift correction every 2 s using gravity vector; maintains <0.5° accuracy even when phone is held at 45° tilt (common in prayer).
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Offline Kaaba coordinate hard-coded at 21.4225° N, 39.8262° E; great-circle bearing calculated with WGS-84 ellipsoid, not spherical approximation → sub-kilometre precision worldwide.
UX We Sweated
AR overlay uses Google’s ARCore but we had to write a custom shader so the white Kaaba-line stays luminance-stable under desert sunlight (tested at 45 °C, 120 k lux). Shader source is MIT-licensed on our GitHub.
AR overlay uses Google’s ARCore but we had to write a custom shader so the white Kaaba-line stays luminance-stable under desert sunlight (tested at 45 °C, 120 k lux). Shader source is MIT-licensed on our GitHub.
Time-Zone Mercy
Prayer-time recalc uses a lightweight port of USNO’s NOVAS library; when jet-lag is detected (GPS delta > 3 h) we ramp each prayer by 20 min per day instead of hard-switching—prevents the “ salah shock” phenomenon confirmed by 1 800 user surveys.
Prayer-time recalc uses a lightweight port of USNO’s NOVAS library; when jet-lag is detected (GPS delta > 3 h) we ramp each prayer by 20 min per day instead of hard-switching—prevents the “ salah shock” phenomenon confirmed by 1 800 user surveys.
Open-Source Bits
Core compass module is Apache-2.0; mosque dataset is CC-BY-SA. Clone, build, submit PRs → qiblasalat.com
Core compass module is Apache-2.0; mosque dataset is CC-BY-SA. Clone, build, submit PRs → qiblasalat.com
磁力计 + 加速度计 → 卡尔曼滤波器 → 俯仰/横滚补偿航向。
陀螺仪每 2 秒使用重力矢量进行漂移校正；即使手机倾斜 45°（祈祷时常见），也能保持 <0.5° 的精度。
离线天房坐标硬编码为北纬 21.4225°，东经 39.8262°；大圆方位角使用 WGS-84 椭球体计算，而非球面近似 → 全球精度可达亚公里级。
用户体验精益求精
AR 叠加层使用 Google 的 ARCore，但我们编写了一个自定义着色器，以确保天房白线在沙漠阳光下保持亮度稳定（测试条件为 45°C，120 k lux）。着色器源代码已在我们的 GitHub 上以 MIT 许可证发布。
时区优化
祈祷时间重新计算使用了 USNO 的 NOVAS 库的轻量级移植版；当检测到时差（GPS 时差 > 3 小时）时，我们会将每次礼拜时间每天增加 20 分钟，而不是直接切换——这可以避免“礼拜冲击”现象，该现象已通过 1800 份用户调查得到证实。
开源信息
核心指南针模块采用 Apache 2.0 许可；清真寺数据集采用 CC-BY-SA 许可。克隆、构建、提交 PR → qiblasalat.com
本文来自投稿，不代表独立开发前线立场，如若转载，请注明出处：https://91wink.com/qiblasalat-crafting-an-ar-compass-that-prays-as-good-as-it-looks-sensor-fusion-recipe/
