wrapLatitude method

double wrapLatitude()

Converts this double value in degrees to a normalized latitude in the range [-90.0, 90.0].

Examples:

• -89.0 => -89.0
• -92.0 => -88.0
• 89.0 => 89.0
• 92.0 => 88.0

As a special case if this is double.nan then double.nan is returned.

See also clipLatitude.

Implementation

double wrapLatitude() {
  if (this >= -90.0 && this <= 90.0) {
    // already normalized
    return this;
  } else {
    if (this > 90.0) {
      // north pole as reference
      final x = (this - 90.0) % 360.0;
      if (x <= 180.0) {
        return 90.0 - x;
      } else {
        return -90.0 + (x - 180.0);
      }
    } else {
      // south pole as reference
      final x = (this + 90.0).abs() % 360.0;
      if (x <= 180.0) {
        return -90.0 + x;
      } else {
        return 90.0 - (x - 180.0);
      }
    }
  }
}