TIFF document

TIFF is WhimTex’s main image-backed document format. Each TIFF document is one *.tiff file: a Unity texture and an editable document at the same time: the visible TIFF image is the last saved composite, while the layer model and Drawing data travel in an appended WhimTex container.

What the file contains

The TIFF image comes first, so Unity can import it with the normal Texture Importer. After the image, WhimTex writes a binary container with a document model block, separate Drawing pixel blocks and a small carrier block. A directory records each block’s name, compression and lengths; the integrity:sha256 manifest detects accidental truncation or modification. This is not a ZIP file and it is not a second Unity asset.

The composite uses 8-bit samples for ordinary output and can use Float32 for HDR or explicit Precision → Float32. Mipmaps, GPU compression, sprite slicing and platform overrides remain normal Unity importer settings rather than document-layer data.

Loading and saving

Opening reads the footer, block directory and model first. Drawing pixel blocks are loaded lazily when rendering, previewing, editing or saving needs them; the whole document is not inflated at once. Saving stages a sibling temporary file, validates it and atomically replaces the previous TIFF. If the source changed externally, WhimTex refuses to combine revisions and asks you to reopen or use Save As.

Compatibility

Do not resave a WhimTex TIFF in an external image editor: it may discard the appended container and leave only the composite image. Legacy .asset documents are unsupported. Convert them to TIFF using WhimTex 0.12.5 before upgrading. JSON documents are an editable text alternative, without Drawing pixels or a Unity texture. PNG, JPEG, TGA and EXR contain the exported image without editable layers. PSD can retain some layers and effects, but does not replace the original WhimTex document.

For the complete byte layout, limits and block-level rules, see the TIFF document format technical reference.