Optimizer finds .ytd, .yft, and .ydr files under stream that are larger than 16 MiB. Only YTD files can be optimized automatically. Large YFT/YDR files are marked Unfixable for manual optimization.

Scan resources

1. Scan a workspace in Scanner.
2. Open Optimizer and click Scan Resources.
3. Review the total stream size and files above 16 MiB.

Results are sorted from largest to smallest. The 16 MiB threshold is a streaming risk indicator, not proof that a file is broken.

Optimize Selected

1. Select no more than ten YTD files.
2. Choose a maximum resolution: 4096, 2048, 1024 (default), or 512.
3. Click Optimize Selected.
4. Wait for extraction, compression, and rebuilding to finish.

For each YTD, the application:

1. creates <file>.backup if that backup does not already exist;
2. extracts the YTD into temporary XML and DDS files;
3. resizes textures to the selected limit and power-of-two dimensions;
4. compresses them as BC3_UNORM/DXT5;
5. generates mipmaps;
6. rebuilds the YTD and removes its temporary directory.

Cancellation is checked between processing steps. The current file is restored from .backup if cancellation interrupts it; earlier completed files stay optimized.

Version 1.2.2 limitation: the Cancel button calls a renderer bridge wrapper that is not currently defined, even though the backend handler exists. Do not rely on Cancel. Select small batches and let them finish; never terminate the process while a YTD is being rebuilt.

Choose a resolution

• 4096: highest detail and the smallest size reduction.
• 2048: a common compromise for large body or livery textures.
• 1024: the application default and a more aggressive reduction.
• 512: useful for small/distant assets but can visibly blur details.

Because every texture is forced to BC3, normal maps or textures intended for BC5/another format can lose quality. Optimize a copy, compare size and visuals, and keep .backup until all testing is complete.