--- title: Specifying a lighting environment in AR Quick Look framework: arkit role: article role_heading: Article path: arkit/specifying-a-lighting-environment-in-ar-quick-look --- # Specifying a lighting environment in AR Quick Look Add metadata to your USDZ file to specify its lighting characteristics. ## Overview Overview AR Quick Look in iOS 16 and later enhances lighting to deliver more brightness, contrast, and visual definition for your scene’s virtual content. You can set an asset’s lighting environment, or image-based lighting (IBL), by adding the preferredIblVersion metadata to the file’s .usda textual definition, or by generating the asset with Apple-provided tools. Set the lighting metadata To define the lighting environment in the asset’s .usda textual format using a tool like USD Toolset, add the following metadata: // asset.usda #usda 1.0 ( customLayerData = { dictionary Apple = { int preferredIblVersion = 2 } } ) A value of 1 indicates the classic lighting environment, and a value of 2 indicates the new lighting environment. If you omit the preferredIblVersion metadata or give it a value of 0, the system checks the asset’s creation timestamp. A timestamp of July 1, 2022, or later results in the new lighting environment; otherwise, the scene features classic lighting for backward compatibility. The system checks the timestamp of the .usd asset within the .usdz archive, not the archive’s file creation date. Set the lighting environment with Apple-provided tools With Reality Converter, you can choose a lighting preference for your 3D asset by previewing the available options one after the other. By default, Reality Converter previews an imported 3D asset with preferrediblversion = 2. You can select the Use Classic Lighting option to set preferrediblversion to 1 in the file. Alternatively, you can use usdzconvert in the Apple USDZ Tools suite to output from another file format. Pass an integer value between 0 and 2 for the --preferrediblversion argument to add this metadata in the file, as the following example shows: usdzconvert fireHydrant.obj --useObjMtl --preferrediblversion 2 Match AR Quick Look lighting in third-party apps and tools To design your content in a third-party digital content creation tool (DCC) under the same lighting conditions as AR Quick Look’s lighting environment, configure the tool to use one of the following .exr files. Alternatively, you can apply an .exr file in your third-party app, such as one that renders with RealityKit, to accommodate the new lighting environment in your app’s runtime experience. The studio_lighting_objectmode_v002.exr file provides reflections that match AR Quick Look’s studio object mode. This IBL is appropriate for asset creation in a third-party DCC. Consult the DCC documentation about enabling custom image-based lighting in the tool. The studio_lighting_armode_v002.exr file provides enhanced highlights according to AR Quick Look’s new lighting environment in AR mode. This IBL is appropriate for use in your AR app as a combination with an environment texture that composes captures of the user’s environment. Together, the combination enhances reflections on your app’s virtual content that feature the particular tints and hues of the real world. tip: For apps that render virtual content using RealityKit, set up a skybox with the AR mode IBL to use the new lighting environment. Although AR Quick Look observes the preferrediblversion metadata, RealityKit doesn’t. See EnvironmentResource for more information about defining image-based lighting in RealityKit. ## See Also ### AR Quick Look - [Previewing a Model with AR Quick Look](arkit/previewing-a-model-with-ar-quick-look.md) - [Adding Visual Effects in AR Quick Look and RealityKit](arkit/adding-visual-effects-in-ar-quick-look-and-realitykit.md) - [Adding an Apple Pay Button or a Custom Action in AR Quick Look](arkit/adding-an-apple-pay-button-or-a-custom-action-in-ar-quick-look.md) - [ARQuickLookPreviewItem](quicklook/arquicklookpreviewitem.md) - [OpenUSD schemas for AR](usd/usd-schemas-for-ar.md)