//

// Scene.swift

// ShapeScript

//

// Created by Nick Lockwood on 27/09/2018.

// Copyright © 2018 Nick Lockwood. All rights reserved.

//

import Euclid

import Foundation

public final class Scene {

public let background: MaterialProperty

public let children: [Geometry]

public let cameras: [Geometry]

public let lights: [Geometry]

public let cache: GeometryCache?

public init(

background: MaterialProperty,

children: [Geometry],

cache: GeometryCache?

) {

self.background = background

self.children = children

self.cameras = children.flatMap(\._cameras)

self.lights = children.flatMap(\._lights)

self.cache = cache

children.forEach { $0.cache = cache }

}

}

extension Scene: Equatable {

public static func == (lhs: Scene, rhs: Scene) -> Bool {

lhs.background == rhs.background &&

lhs.children == rhs.children &&

lhs.cameras == rhs.cameras

}

}

public extension Scene {

static let empty = Scene(background: .color(.clear), children: [], cache: nil)

/// Returns the approximate (overestimated) bounds of the scene geometry.

var overestimatedBounds: Bounds {

Bounds(children.map(\.overestimatedBounds))

}

/// Returns the approximate (overestimated) bounds of the scene geometry.

@available(*, deprecated, renamed: "overestimatedBounds")

var bounds: Bounds {

overestimatedBounds

}

func build(_ callback: @escaping LegacyCallback) -> Bool {

for geometry in children where !geometry.build(callback) {

return false

}

return true

}

}

private extension Geometry {

var _cameras: [Geometry] {

guard case .camera = type else {

return children.flatMap(\._cameras)

}

return [self]

}

var _lights: [Geometry] {

guard case .light = type else {

return children.flatMap(\._lights)

}

return [self]

}

}