# init(x:y:z:) Creates a rectangle mark for a 3D chart. ``` nonisolated init(x: PlottableValue, y: PlottableValue, z: PlottableValue) ``` ## Parameters `x` The x value. `y` The y value. `z` The z value. ## Discussion> Important: A 3D RectangleMark requires one parameter to be a single numeric value and the other two parameters to be numeric ranges. For example, the following `Chart3D` shows a rectangle mark that extends along the x-axis and y-axis. ```swift Chart3D { RectangleMark( x: .value("x", -0.5..<0.5), y: .value("y", -0.5..<0.5), z: .value("z", 0) ) } ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)