Content

The .drft container

140 symbols, imported from @driftengine/drft.

Explained in The .drft container.

Classes

DrftError: Thrown for any malformed or unreadable file, with the offset that failed.
DrftStream: An incremental .drft reader: feed it bytes, it reports each chunk as that chunk completes.
RegionLedger: What regions must be to each other: an id once, a level mesh in one region's one level, and a group's prototype never also a level mesh. Kept across chunks by the writer, the whole-file reader and the stream alike, so a file one of them refuses the others refuse too.

Interfaces

AnimationClip
BcImage: A block-compressed image, as a CODEC_BC payload holds it.
DrftAssembly
DrftAsset: A decoded asset. See docs/FORMAT.md for what each chunk carries.
DrftGraph
DrftGraphNode
DrftGraphTensor
DrftGraphValue
DrftHead: What HEAD says about the asset as a whole.
DrftInstanceGroup
DrftLight
DrftLightVolume: The same shape as core's DenseLightVolume, so a read volume goes straight to the renderer.
DrftManifest: What the file says is coming, known from the first few kilobytes.
DrftMaterial: One surface, stored once per mesh rather than once per vertex.
DrftMorph: One mesh's morph deltas, and which mesh they belong to.
DrftNetwork
DrftNnet
DrftNode: A node in the asset's own hierarchy. mesh is -1 for a node that draws nothing.
DrftRegion
DrftRegionCollision
DrftRegionLevel
DrftSdfv
DrftSdfvEntry
DrftSkin: A skin: the joints, their inverse bind matrices, and nothing about how it is played.
DrftSource: What a caller hands over to be baked.
DrftSplatBlock: One block of a capture, as the reader hands it back.
DrftSplats: A capture, as the writer is handed it.
DrftStreamHandlers: Called as each kind of thing finishes arriving. Every one is optional.
DrftStreamPacing: When a stream stops to let something else run, and how.
DrftSubs
DrftSubstanceEntry
DrftTexture: An embedded image, still compressed. Decoding is the consumer's, through createImageBitmap.
DrftTextureSource: An image to embed, already compressed, with what its own header said about it.
DtexEntry: A material's decode program, and which MATL entry it belongs to.
DtexMaterial
EntsScene: A world as data. @driftengine/entities' SerializedScene is one of these.
Joint: One joint: where it hangs and what it is called.
JointTrack: One joint's keys for one of its three transforms.
MeshData: A description of vertex data, and the check that it is coherent.
MeshletLevel
NavPolyMesh: A polygon mesh and where it stands. @driftengine/nav's PolyMesh is one of these.

Functions

assemblyBounds: Min xyz then max xyz of every copy: its piece's box through its matrix, corner by corner.
bcChainLength: How many levels a full chain from width by height down to 1x1 has.
bcLevelBytes: The bytes level level of a width by height surface takes in format.
buildAssembly
buildClip
buildColliders
buildDtex
buildEnts
buildInstances
buildKit
buildLights
buildLightVolume
buildMeshlets
buildMorph
buildNavm
buildNgrf: Write the chunk. Refuses anything a reader would have to guess about.
buildNnet: Write the chunk. Refuses anything a reader would have to guess about.
buildNodes
buildRegion
buildSdfv: Write the chunk. Refuses anything a reader would have to guess about.
buildSkin
buildSubs: u32 count, then per entry: u32 material, u32 name bytes, then the UTF-8 name.
checkAssembly: What an assembly must be on its own: known bits, whole records, surfaces it names, finite numbers, whole layers, and no copy flattened to nothing — whose normals would be a division by zero rather than a direction.
checkCopies: What an assembly must be to the kit around it: every copy a declared piece that comes before it in the file — so a streaming reader holds the piece when the copy lands — and every piece carrying what the assembly asks of it. Shared by the writer and both readers, so a file one refuses the others refuse too.
coarseFirstOrder: The order to write a capture's splats in, so that every prefix of the file is a complete sparse capture rather than a finished corner of one.
codecName: What a codec is called, for a message naming what was not understood.
expandAssembly
isAssembly: Whether a mesh slot holds an assembly rather than vertices.
nnetWeightCount: How many weights and biases a shape needs, in evalNetwork's layout.
planRegions: Where each region's chunk goes among the meshes: before[m] is the regions written just ahead of mesh m, and before[meshCount] those after the last. A streaming reader then always has a region before the meshes it introduces.
readAssembly: One MSHC payload, checked on its own; its pieces are the caller's to check.
readBcPayload: A payload read back, its levels as views over bytes.
readClip
readColliders: The hulls a COLL chunk carries, as views over the fetched buffer.
readDrft
readDtex: The material a DTEX chunk carries, as views over the fetched buffer.
readEnts: The scene an ENTS chunk carries.
readInstances: The groups in an INST payload, each checked against the file's mesh count.
readKit: The kit's pieces, ascending and each a mesh the file carries.
readLights: The lights in a LITE payload.
readLightVolume
readMeshlets: The level an MSHL chunk carries, as views over the fetched buffer.
readMorph
readNavm: The mesh a NAVM chunk carries, as views over the fetched buffer.
readNgrf: Read the chunk, refusing every structure and offset a reader would otherwise have to trust.
readNnet: Read the chunk, refusing every shape a reader would otherwise have to trust.
readNodes
readRegion: One REGN payload, checked on its own against the file's mesh count.
readSdfv: Read the chunk, refusing every shape a reader would otherwise have to trust.
readSkin
readSubs
streamDrft: Read a .drft from a fetch response as it arrives.
validateMeshData: Every attribute covers every vertex, and every index names one that exists.
writeBcPayload: The payload for image. Refuses a level whose size is not the one its position requires.
writeDrft: Bake a .drft into one ArrayBuffer.

Types

BcFormat: The block formats a CODEC_BC payload may hold: what one 4x4 block of texels encodes.
DrftAttribute
DrftLightKind
PieceLookup: Finds a kit piece by mesh ordinal.
TrackPath: Which of a joint's three transforms a track drives.

Constants

ASSEMBLY_ATTRIBUTES: The optional arrays an assembled mesh may carry. Skinning is a piece of a character, not a kit.
ATTR_CHANNEL: Added in 1.23: MeshData.channel, four floats a vertex — sway, sky, opacity, and a spare lane.
ATTR_EMISSIVE_COLOR
ATTR_GRAIN: Added in 1.1, and the worked example of why the order is frozen rather than tidy.
ATTR_LAYERS: Added in 1.20: which image of a texture array each vertex's face wears. See MeshData.layers.
ATTR_RELIEF: Added in 1.3, and it is the same story as grain one bit along.
ATTR_ROUGHNESS
ATTR_SPECULAR: Which optional attributes a MESH chunk carries.
ATTR_TANGENT: Added in 1.4, and the first optional attribute wider than three floats a vertex.
ATTR_UVS
BC_BLOCK_BYTES: Bytes per 4x4 block of each format.
CODEC_BC: Added in 1.24: block-compressed images, kept as the blocks they were authored in.
CODEC_JPEG
CODEC_PNG: How a TEXS payload is encoded.
CODEC_RAW
CODEC_WEBP
COPY_MATRIX_FLOATS: A copy's matrix: three columns of the linear part, then the translation.
COPY_UV_FLOATS: A copy's texture stretch: u along each piece axis, v along each, then the offset.
DEFAULT_STREAM_SLICE_MS: How long a stream may work before it gives way for a task, in milliseconds. The loader's own frame budget is six, and this is the same share of a 60 Hz frame for the same reason.
DRFT_VERSION_MAJOR: The generation of the layout. Bumped only when a byte changes meaning.
DRFT_VERSION_MINOR: Additive revisions within a generation: new optional chunks, new attribute bits, new enum values with a defined fallback. Never a changed meaning.
DTEX_ADDRESS_MODES: Address modes the decode vocabulary has. Mirrors ADDRESS_MODE_COUNT; asserted equal by a test.
DTEX_MAX_TILES: How many tiles one material may carry. Well past what a streaming budget permits.
DTEX_REGISTERS: Registers the decode vocabulary has. Mirrors MAX_REGISTERS; asserted equal by a test.
MAX_CLUSTERS: How many clusters one level may carry. Well past what a streaming budget permits.
MAX_COLLIDER_HULLS: A cap on hulls per asset, so a malformed length cannot ask a reader for gigabytes.
MAX_COLLIDER_POINTS: How many points one hull may carry, which is what hullShape accepts.
NNET_ENTRY_BYTES: Role, three counts, eight widths, precision and weight count.
NNET_MAX_HIDDEN: Hidden layers the entry table has room for.
NNET_MAX_WIDTH: The widest layer a network may declare.
REGION_MAX_LEVELS: The most levels a region may carry; the runtime keeps one value of a byte for "none".
SDFV_ENTRY_BYTES: u32 mesh, three u32 dimensions and six f32 bounds. A field's samples are elsewhere.
SDFV_MAX_SAMPLES: The most samples one field may declare.
SDFV_WHOLE_FILE: The mesh ordinal that means the file's static geometry as a whole, in the file's own space.
SURFACE: Where each value sits in a surface, whichever of them the mesh carries.
SURFACE_FLOATS