Function

Gdkevents_get_angle

Declaration [src]

gboolean
gdk_events_get_angle (
  GdkEvent* event1,
  GdkEvent* event2,
  double* angle
)

Description [src]

Returns the relative angle from event1 to event2.

The relative angle is the angle between the X axis and the line through both events’ positions. The rotation direction for positive angles is from the positive X axis towards the positive Y axis.

This assumes that both events have X/Y information. If not, this function returns FALSE.

Parameters

event1

Type: GdkEvent

First GdkEvent.

The data is owned by the caller of the function.

event2

Type: GdkEvent

Second GdkEvent.

The data is owned by the caller of the function.

angle

Type: double*

Return location for the relative angle between both events.

The argument will be set by the function.

Return value

Type: gboolean

TRUE if the angle could be calculated.