# addUniform(_:) Adds a uniform to the shader. ``` func addUniform(_ uniform: SKUniform) ``` ## Parameters `uniform` The new uniform object to add. The uniform object’s name must not already be in use by another uniform attached to the shader. ## Discussion The uniform variable is automatically accessible inside your shader; do not add a declaration for it in your shader’s source code. The uniform *must* be accessed in the fragment shader. --- 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)