Question

是否可以使用Flutter指南针找到特定方向。该指南针指示特定的长坐标和纬坐标吗？

Answer 1

这是我在应用中使用的Qibla指南针的标准代码，以获取偏移量：

  double getOffsetFromNorth(double currentLatitude, double currentLongitude,
      double targetLatitude, double targetLongitude) {
    var la_rad = radians(currentLatitude);
    var lo_rad = radians(currentLongitude);

    var de_la = radians(targetLatitude);
    var de_lo = radians(targetLongitude);

    var toDegrees = degrees(atan(sin(de_lo - lo_rad) /
        ((cos(la_rad) * tan(de_la)) - (sin(la_rad) * cos(de_lo - lo_rad)))));
    if (la_rad > de_la) {
      if ((lo_rad > de_lo || lo_rad < radians(-180.0) + de_lo) &&
          toDegrees > 0.0 &&
          toDegrees <= 90.0) {
        toDegrees += 180.0;
      } else if (lo_rad <= de_lo &&
          lo_rad >= radians(-180.0) + de_lo &&
          toDegrees > -90.0 &&
          toDegrees < 0.0) {
        toDegrees += 180.0;
      }
    }
    if (la_rad < de_la) {
      if ((lo_rad > de_lo || lo_rad < radians(-180.0) + de_lo) &&
          toDegrees > 0.0 &&
          toDegrees < 90.0) {
        toDegrees += 180.0;
      }
      if (lo_rad <= de_lo &&
          lo_rad >= radians(-180.0) + de_lo &&
          toDegrees > -90.0 &&
          toDegrees <= 0.0) {
        toDegrees += 180.0;
      }
    }
    return toDegrees;
  }

然后将偏移量添加到flutter_compass旋转以获取每个偏移量传感器更新并将结果应用于特殊标头。

如何用颤振罗盘找到方向？

1 个答案: