# setObject(_:forKeyedSubscript:) Sets a value for the specified shader variable or attribute name, using subscript syntax. ``` func setObject(_ obj: Any?, forKeyedSubscript key: any NSCopying) ``` ## Parameters `obj` An object containing a new value for the shader symbol. `key` A shader variable or attribute name used in one of the technique’s shader programs. ## Discussion The `value` parameter should be an object appropriate to the type of the shader symbol being set. For example, use an object to set the value of a `float` uniform variable, or use an object containing an [`SCNVector3`](/documentation/SceneKit/SCNVector3) structure to set the value of a GLSL `vec3` uniform variable or a Metal `float3` variable. Use this method when you need to set a value infrequently or only once. To update a shader value every time SceneKit renders a frame, use the [`handleBinding(ofSymbol:using:)`](/documentation/SceneKit/SCNTechnique/handleBinding(ofSymbol:using:)) method instead. If you use the [`handleBinding(ofSymbol:using:)`](/documentation/SceneKit/SCNTechnique/handleBinding(ofSymbol:using:)) method to associate a handler block for a symbol, SceneKit ignores values set for the symbol using the [`setObject(_:forKeyedSubscript:)`](/documentation/SceneKit/SCNTechnique/setObject(_:forKeyedSubscript:)) method. --- 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)