Initializer

init(radialSpace:start:startRadius:end:endRadius:function:extendStart:extendEnd:)

Creates a shading object to use for radial shading.

Declaration

init?(radialSpace space: CGColorSpace, start: CGPoint, startRadius: CGFloat, end: CGPoint, endRadius: CGFloat, function: CGFunction, extendStart: Bool, extendEnd: Bool)

Parameters

colorspace

The color space in which color values are expressed. Core Graphics retains this object; upon return, you may safely release it.

start

The center of the starting circle, in the shading's target coordinate space.

startRadius

The radius of the starting circle, in the shading's target coordinate space.

end

The center of the ending circle, in the shading's target coordinate space.

endRadius

The radius of the ending circle, in the shading's target coordinate space.

function

A CGFunction object created by the function init(info:domainDimension:domain:rangeDimension:range:callbacks:). This object refers to your function for creating a radial shading. Core Graphics retains this object; upon return, you may safely release it.

extendStart

A Boolean value that specifies whether to extend the shading beyond the starting circle.

extendEnd

A Boolean value that specifies whether to extend the shading beyond the ending circle.

Return Value

A new Core Graphics radial shading. You are responsible for releasing this object using CGShadingRelease.

Discussion

A radial shading is a color blend that varies between two circles. To draw the shading, call the function drawShading(_:).

See Also