…colormultiply

.brightness(_:)	Adjusts the brightness of the view
.contrast(_:)	Adjusts the contrast of the view
.saturation(_:)	Adjusts the color saturation of the view
.hueRotation(_:)	Rotates the hue of the view's colors by an angle
.colorMultiply(_:)	Multiplies the view's colors by a specified color

float casting is annoying, could probably be made cleaner with something like
let hueMatrix = ColorMatrix(values.map { Float($0) }.toFloatArray())