init(attribute:relativeTo:attribute:scale:offset:)
Returns an CAConstraint object with the specified parameters. Designated initializer.
Declaration
init(attribute attr: CAConstraintAttribute, relativeTo srcId: String, attribute srcAttr: CAConstraintAttribute, scale m: CGFloat, offset c: CGFloat)Parameters
- attr:
The attribute of the layer for which to create a new constraint.
- srcId:
The name of the layer that this constraint is calculated relative to.
- srcAttr:
The attribute of
srcLayerthe constraint is calculated relative to. - m:
The amount to scale the value of
srcAttr. - c:
The offset added to the value of
srcAttr.
Return Value
An initialized constraint object using the specified parameters.
Discussion
The value for the constraint is calculated as (srcAttr * scale) + offset).