Action #1124

implement region rotation

Added by Kosack Karl about 10 years ago. Updated about 8 years ago.

Status:NewStart date:01/30/2014
Priority:NormalDue date:
Assigned To:-% Done:

0%

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Target version:-
Duration:

Description

to implement a correct reflected-region background method, GSkyRegions must have a rotation angle implemented, so that arbitrary regions end up in the correct orientation on the sky.

The suggested way to implement this is to add:
@
GSkyDir m_rotation_point;
double m_rotation_angle;

GSkyDir  transform_to_region_system( GSkyDir &dir );
GSkyDir transform_from_region_system( GSkyDir &dir);


to the base GSkyRegion class. The transformation functions apply the rotation to any point for the current region, and should be applied in @contains()
etc., before checking if a coordinate is inside a region. This way the mathematical definition of the regions does not need to take into account rotation. E.g. a rectangle region can be assumed to be aligned to the X-Y axis, and rotation is taken into account by the coordinate transformation.


Recurrence

No recurrence.

History

#1 Updated by Knödlseder Jürgen about 10 years ago

  • Target version set to 2nd coding sprint

#2 Updated by Knödlseder Jürgen over 9 years ago

  • Target version deleted (2nd coding sprint)

#3 Updated by Martin Pierrick about 8 years ago

  • Parent task deleted (#1044)

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