(c) 1996-97 Bert Freudenberg, neŽ Schönwälder, (bert@isg.cs.uni-magdeburg.de) University of Magdeburg, Germany.

Modified 1998 by Andreas Raab (Andreas.Raab@disney.com) for Squeak.

Class ThreeDSParser reads a 3DS File (AutoDesk 3D Studio's native format). It isn't a real parser at all, I chose this name for consistency with the other scene parser classes. For description of 3DS format I used "The Unofficial 3DStudio 3DS File Format v1.0" by Jeff Lewis and the "3ds_bin" by Jim Pitts et. al., see #chunkDocumentation on the Class side.

Instance Variables:
source <Stream> binary stream on source file
chunkPos <Integer> File position of current chunk
chunkID <Integer> ID of current cunk
chunkLen <Integer> Length of current chunk
indent <Integer | nil> If nil, no log is written. Otherwise the current nesting level.
informer <Block> A block taking the progress value while reading
classSpec <Dictionary | nil> Specification of the classes to construct.

Class Variables:
ChunkDescriptions <Dictionary of: ThreeDSChunkDescription>
For debugging only. ChunkDescriptions generated from the documentation
DefaultSpec <Dictionary | nil>
The default class specification to use.

	construction classes
	cameraClass materialClass meshObjectClass pointLightClass sceneClass specAt: specAt:ifAbsent: splineVertexClass spotLightClass textureArrayClass vertexArrayClass

	dispatching
	recognize: recognize:as: recognize:do: recognize:do:inChunksUpTo:

	executing
	indexed:do:do: indexed:do:do:do: indexed:doBlocks:

	initialize-release
	classSpec: parse: parse:using: parseFileNamed: parseFileNamed:using: parseStream:

	private
	chunkHeader logUnreadBytes: printChunkInfo

	private-dispatching
	dispatchID:in: findID:in: getSelectorFor:in: makeResult:for:in:

	private-util
	chunkDescriptionFor:

	reading
	scene

	reading-keyframe
	keyframeData keyframeHeader node nodeHeader trackCString trackCollect: trackColor trackFlag trackFloat trackRotation trackVector

	reading-material
	materialColor materialEntry textureMap textureVertices verticalGradient

	reading-mesh
	camera light meshData namedObject smoothList spot triList triMesh vertexList

	reading-primitives
	cString color24 colorFloat container flag float long matrix percentageChunk short twoFloats twoLongs twoShorts twoVector3 uLong uShort vector3

	instance creation
	parse: parse:using: parseFileNamed: parseFileNamed:using:

	utilities
	chunkDescriptionFor: chunkDescriptions chunkDocumentation clearChunkDescriptions initializeChunkDescriptions

	accessing	top
	informer
	informer:

	construction classes	top
	cameraClass
	materialClass
	meshObjectClass
	pointLightClass
	sceneClass
	specAt:
	specAt:ifAbsent:
	splineVertexClass
	spotLightClass
	textureArrayClass
	vertexArrayClass

	dispatching	top
	recognize: Answer first item found
	recognize:as: Collect all items in a new resultCollectionClass
	recognize:do: Provide default end position
	recognize:do:inChunksUpTo: Scan chunks up to endPos, process those mentioned in dispatcherArray

	executing	top
	indexed:do:do: According to item's key evaluate one of the blocks with item's value
	indexed:do:do:do: According to item's key evaluate one of the blocks with item's value
	indexed:doBlocks: According to item's key evaluate one of the blocks with item's value

	initialize-release	top
	classSpec:
	parse: Read the 3DS file from the given stream
	parse:using: Read the 3DS file from the given stream
	parseFileNamed: Read the 3DS file from the given stream
	parseFileNamed:using: Read the 3DS file from the given stream
	parseStream: Read the 3DS file from the given stream

	private	top
	chunkHeader Read header of a chunk, store in instance variables
	logUnreadBytes:
	printChunkInfo

	private-dispatching	top
	dispatchID:in: Look for id in dispatcher, and process it, if found
	findID:in: Return index of id in dispatcher, nil if not found
	getSelectorFor:in: Return method selector
	makeResult:for:in: Answer Association if needed

	private-util	top
	chunkDescriptionFor: Answer chunk description for id

	reading	top
	scene Whole file

	reading-keyframe	top
	keyframeData Subchunk of scene
	keyframeHeader Subchunk of keyframeData
	node Subchunk of keyframeData
	nodeHeader Subchunk of node
	trackCString Read keyframes defining a string (morph)
	trackCollect: Read keyframes, return Array with values of aBlock
	trackColor Read keyframes interpolating a color
	trackFlag Read keyframes for a flag (hide)
	trackFloat Read keyframes interpolating a float (hotspot, falloff, roll, etc.)
	trackRotation Read keyframes interpolating a rotation
	trackVector Read keyframes interpolating a vector (position, scale)

	reading-material	top
	materialColor
	materialEntry Globally defined materials
	textureMap
	textureVertices Subchunk of tri object
	verticalGradient

	reading-mesh	top
	camera Subchunk of namedObject
	light Subchunk of namedObject
	meshData Subchunk of scene
	namedObject Subchunk of meshData
	smoothList Optional subchunk of faceList
	spot Subchunk of light
	triList Subchunk of triMesh
	triMesh Subchunk of namedObject
	vertexList Subchunk of triMesh

	reading-primitives	top
	cString Generic Subchunk containing a cstring
	color24 Color from 3 bytes
	colorFloat Color from 3 floats
	container Generic container chunk
	flag Generic Subchunk -- if found, answer true
	float Generic Subchunk containing a float
	long Generic Subchunk containing a long
	matrix float matrix[4][3]
	percentageChunk
	short Generic Subchunk containing a short
	twoFloats Generic Subchunk containing two floats
	twoLongs Generic Subchunk containing two longs
	twoShorts Generic Subchunk containing two shorts
	twoVector3 Generic Subchunk containing two points
	uLong Generic Subchunk containing a long
	uShort Generic Subchunk containing a short
	vector3 Generic Subchunk containing a vector

	class initialization	top
	defaultSpec The default spec is a dictionary with #camera -> CameraClassName (e.g., #B3DCamera3DS) #material -> MaterialClassName (e.g., #B3DMaterial3DS) #meshObject -> MeshObjectClassName (e.g., #B3DObject3DS) #pointLight -> PointLightClassName (e.g., #B3DPositionalLight) #spotLight -> SpotLightClassName (e.g., #B3DSpotLight) #scene -> SceneClassName (e.g., #B3DScene3DS) #splineVertex -> SplineVertexClass (e.g., B3DSplineVertex3DS) all responding to #from3DS: aDictionary and #vertexArray -> VertexArrayClassName (e.g., #B3DVector3Array) #textureArray -> TextureArrayClassName (e.g., #B3DTexture2Array) for constructing large arrays of vertex / texture coordinates (responding to the standard array messages #new: #at: and #at:put:)
	defaultSpec: ThreeDSParser defaultSpec
	initialize ThreeDSParser initialize
	initializeB3D ThreeDSParser initializeB3D

	instance creation	top
	parse: Answer a dictionary of name->RenderObject associations
	parse:using: Answer a dictionary of name->RenderObject associations
	parseFileNamed: Answer a dictionary of name->RenderObject associations
	parseFileNamed:using: Answer a dictionary of name->RenderObject associations

	utilities	top
	chunkDescriptionFor: Answer chunk description for id
	chunkDescriptions
	chunkDocumentation From: The Unofficial 3DStudio 3DS File Format v1.0 by Jeff Lewis
	clearChunkDescriptions Reset Class variable ChunkDescriptions
	initializeChunkDescriptions Initialize Class variable ChunkDescriptions from the documentation