compressed_image_saver.md

title	`CompressedImageSaver` improvements
pull_requests	23567

The compressed_image_saver Cargo feature has been reworked. The old behavior (Basis Universal UASTC compression) has been moved to a new feature called compressed_image_saver_universal, and the compressed_image_saver feature now uses the ctt library to compress textures into BCn (desktop) or ASTC (mobile) formats instead.

If you were using the compressed_image_saver feature and want to keep the previous Basis Universal behavior, rename the feature in your Cargo.toml:

# Before
bevy = { version = "0.18", features = ["compressed_image_saver"] }

# After (keeps old Basis Universal behavior)
bevy = { version = "0.19", features = ["compressed_image_saver_universal"] }

Alternatively, keep using compressed_image_saver to get the new BCn/ASTC compression backend. This produces higher-quality output and supports a wider range of input formats, but does not support all platforms in a single file like UASTC does. We recommend sticking to compressed_image_saver_universal when targeting the web.

CompressedImageSaverError has a new variant CompressionFailed. If you were matching exhaustively on this enum, add a branch for it.