ARK-OS/arkos/arkrt/ark.ui.basic/Sources/Backend/BackendFeatures/Paths.swift

public typealias UIPath = Path

extension BackendFeatures {
    /// Backend methods for path rendering.
    ///
    /// These are used by ``Shape`` and related types and modifiers.
    @MainActor
    public protocol Paths<Path>: Core {
        /// The underlying path type. Can be a wrapper or subclass.
        associatedtype Path

        /// Create a widget that can contain a path.
        ///
        /// - Returns: A path widget.
        func createPathWidget() -> Widget

        /// Create a path.
        ///
        /// - Returns: An empty path.
        func createPath() -> Path

        /// Add the instructions from a path to a backend path.
        ///
        /// The instructions shouldn't be added to the path again on subsequent updates. Wait for
        /// `updatePath` to be called with `pointsChanged == true` before re-applying instructions.
        ///
        /// If a backend's path isn't mutable, this method should return the new path rather than
        /// updating it in-place. Alternatively, the old path can be mutated in-place and returned.
        ///
        /// - Parameters:
        ///   - path: The backend path to update.
        ///   - source: The path instructions.
        ///   - bounds: The bounds that the path is being rendered within.
        ///   - pointsChanged: An indicator of whether the instructions have changed since the last
        ///     call to this method. The backend can use this to optimize when updates occur.
        ///   - environment: The environment of the path.
        func updatePath(
            _ path: Path,
            _ source: UIPath,
            bounds: UIPath.Rect,
            pointsChanged: Bool,
            environment: EnvironmentValues
        )

        /// Draw a path to the screen.
        ///
        /// - Parameters:
        ///   - path: The path to be rendered.
        ///   - container: The container widget that the path will render in.
        ///     Created with ``createPathWidget()``.
        ///   - strokeColor: The color to draw the path's stroke.
        ///   - fillColor: The color to shade the path's fill.
        ///   - overrideStrokeStyle: A value to override the path's stroke style.
        func renderPath(
            _ path: Path,
            container: Widget,
            strokeColor: Color.Resolved,
            fillColor: Color.Resolved,
            overrideStrokeStyle: StrokeStyle?
        )
    }
}