daveb1034/NVGTools

Ellipse Rotation

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The rotation for an ellipse is incorrectly implemented. Rotation for ellipses is specified in degrees clockwise from North. Tool implements as anti-clockwise from East. This should be fixed using the geo2arithmetic function.

This is the definition of the angles in the NVG version 1.4.0 specification

4.4.1.1.4 Angles

  • All angles are expressed in degrees with a range of [0.0 to 360.0]. Rotation from 0.0 to
    360.0 is in the clockwise direction. When the angle indicates direction 0.0 indicates
    North. If a value is not specified a value of 0.0 is implied.
  • Where start and stop angles indicate a range, the range proceeds from the start angle to
    the stop angle in a clockwise direction.
  • Where an angle indicates rotation, the rotation is in the counter-clockwise direction. If
    a value is not specified a value of 0.0 is implied.

The last bullet point is relevant to the ellipses.