Color in SCNNodes - ios

Question

I am trying to set the color of a SCNNode to a custom RGBA Color however when I try to the box will end up white:
let box = SCNBox(width: 4, height: 1, length: 4, chamferRadius: 0)
let boxNode = SCNNode(geometry: box)
myScene.rootNode.addChildNode(boxNode)
boxNode.castsShadow = true
box.firstMaterial?.diffuse.contents = UIColor(red: 30, green: 150, blue: 30, alpha: 1)
This makes the box white however doing something like this works:
box.firstMaterial?.diffuse.contents = UIColor.greenColor()
How can I make the box have a custom RGBA color?
-Thanks

Answer 1

The values passed to the UIColor initializer need to be between 0 and 1. You should divide your rgb values by 255.
box.firstMaterial?.diffuse.contents = UIColor(red: 30.0 / 255.0, green: 150.0 / 255.0, blue: 30.0 / 255.0, alpha: 1)

Answer 2

For convenience, you can also add an UIColor extension
extension UIColor {
convenience init(red: UInt, green: UInt, blue: UInt, alpha: UInt = 0xFF) {
self.init(
red: CGFloat(red) / 255.0,
green: CGFloat(green) / 255.0,
blue: CGFloat(blue) / 255.0,
alpha: CGFloat(alpha) / 255.0
)
}
}
And then you can use it as follow:
box.firstMaterial?.diffuse.contents = UIColor(red: 30, green: 150, blue: 30, alpha: 1.0)
Alternatively if you wish to use hex values, add the next UIColor extension
extension UIColor {
convenience init(argb: UInt) {
self.init(
red: CGFloat((argb & 0xFF0000) >> 16) / 255.0,
green: CGFloat((argb & 0x00FF00) >> 8) / 255.0,
blue: CGFloat(argb & 0x0000FF) / 255.0,
alpha: CGFloat((argb & 0xFF000000) >> 24) / 255.0
)
}
}
And use it as follow:
box.firstMaterial?.diffuse.contents = UIColor(argb: 0xFF1B98F5)
Happy Coding 👨‍💻