Angles

Home

In API functions and object properties, angle is specified in radians, counter-clockwise from 0-X axis.

For user unterface (messages, dialogs), various angle units can be used. It is set by following drawing's parameters:

Property	Type	Access	Meaning
LC_PROP_DRW_AUNITS	int	RW	Angle units (see below)
LC_PROP_DRW_AUPREC	int	RW	Display precision for angular units (0..8)
LC_PROP_DRW_ANGBASE	float	RW	Base angle, degrees, counterclockwise from 0-X axis
LC_PROP_DRW_ANGDIR	bool int	RW	Angle direction from base angle, FALSE-counterclockwise, TRUE-clockwise 0 - counterclockwise, 1 - clockwise

The following constants can be used for LC_PROP_DRW_AUNITS property:

Constant	Angle units
LC_AUNIT_DEGREE	Decimal Degrees
LC_AUNIT_DMS	Degrees, minutes, seconds by format ddd_mm_ss_ where the separator symbols are defined by LC_PROP_G_ANGSEPDMS property
LC_AUNIT_GRAD	Grads
LC_AUNIT_RADIAN	Radians

The following constants can be used in API functions to specify angle value:

Constant	Value	Meaning
LC_DEG45 LC_PI4	0.78539816339744830962	45 degrees
LC_DEG90 LC_PI2	1.57079632679489661923	90 degrees
LC_DEG180 LC_PI	3.14159265358979323846	180 degrees
LC_DEG270	4.71238898038468985769	270 degrees
LC_DEG360 LC_2PI	6.28318530717958647692	360 degrees
LC_RAD_TO_DEG	57.2957795130823208	Coefficient for converting radians to degrees
LC_DEG_TO_RAD	0.0174532925199433	Coefficient for converting degrees to radians

See Also

   Drawing's properties