Values for SIMD3 and SIMD2 not showing up in Reality Composer Pro

Reality Composer Pro question related to custom components

My custom component defines some properties to edit in RCP. Simple ones work find, but SIMD3 and SIMD2 do not. I'd expect to see default values but instead I get this 0s. If I try to run this the scene doesn't load. Once I enter some values it does and build and run again it works fine.

More generally, does Apple have documentation on creating properties for components? The only examples I've seen show simple strings and floats. There are no details about vectors, conditional options, grouping properties, etc.

public struct EntitySpawnerComponent: Component, Codable {
    public enum SpawnShape: String, Codable {
        case domeUpper
        case domeLower
        case sphere
        case box
        case plane
        case circle
    }
    
    // These prooerties get their default values in RCP
    /// The number of clones to create
    public var Copies: Int = 12
    /// The shape to spawn entities in
    public var SpawnShape: SpawnShape = .domeUpper
    /// Radius for spherical shapes (dome, sphere, circle)
    public var Radius: Float = 5.0
   
    // These properties DO NOT get their default values in RCP. The all show 0
    /// Dimensions for box spawning (width, height, depth)
    public var BoxDimensions: SIMD3<Float> = SIMD3(2.0, 2.0, 2.0)
   
    /// Dimensions for plane spawning (width, depth)
    public var PlaneDimensions: SIMD2<Float> = SIMD2(2.0, 2.0)
   
    /// Track if we've already spawned copies
    public var HasSpawned: Bool = false
    
    public init() {

    }
}

Answered by radicalappdev in 817179022

Jessy on Bluesky answered this. Apparently components, can only use literals for their initial values

https://bsky.app/profile/jessymeow.bsky.social/post/3lcteyvd6422o

public var BoxDimensions: SIMD3<Float> = [2.0, 2.0, 2.0]
public var PlaneDimensions: SIMD2<Float> = [2.0, 2.0]
Accepted Answer

Jessy on Bluesky answered this. Apparently components, can only use literals for their initial values

https://bsky.app/profile/jessymeow.bsky.social/post/3lcteyvd6422o

public var BoxDimensions: SIMD3<Float> = [2.0, 2.0, 2.0]
public var PlaneDimensions: SIMD2<Float> = [2.0, 2.0]
Values for SIMD3 and SIMD2 not showing up in Reality Composer Pro
 
 
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