Files
2017-03-11 15:22:17 +01:00

405 lines
8.5 KiB
JavaScript

/**
* @author herzig / http://github.com/herzig
*
* Description: reads BVH files and outputs a single THREE.Skeleton and an THREE.AnimationClip
*
* Currently only supports bvh files containing a single root.
*
*/
THREE.BVHLoader = function( manager ) {
this.animateBonePositions = true;
this.animateBoneRotations = true;
this.manager = ( manager !== undefined ) ? manager : THREE.DefaultLoadingManager;
};
THREE.BVHLoader.prototype = {
constructor: THREE.BVHLoader,
load: function ( url, onLoad, onProgress, onError ) {
var scope = this;
var loader = new THREE.FileLoader( scope.manager );
loader.setResponseType( 'arraybuffer' );
loader.load( url, function( buffer ) {
onLoad( scope.parse( buffer ) );
}, onProgress, onError );
},
parse: function ( buffer ) {
/*
reads a string array (lines) from a BVH file
and outputs a skeleton structure including motion data
returns thee root node:
{ name: "", channels: [], children: [] }
*/
function readBvh( lines ) {
// read model structure
if ( nextLine( lines ) !== "HIERARCHY" ) {
throw "HIERARCHY expected";
}
var list = []; // collects flat array of all bones
var root = readNode( lines, nextLine( lines ), list );
// read motion data
if ( nextLine( lines ) != "MOTION" ) {
throw "MOTION expected";
}
// number of frames
var tokens = nextLine( lines ).split( /[\s]+/ );
var numFrames = parseInt( tokens[ 1 ] );
if ( isNaN( numFrames ) ) {
throw "Failed to read number of frames.";
}
// frame time
tokens = nextLine( lines ).split( /[\s]+/ );
var frameTime = parseFloat( tokens[ 2 ] );
if ( isNaN( frameTime ) ) {
throw "Failed to read frame time.";
}
// read frame data line by line
for ( var i = 0; i < numFrames; ++ i ) {
tokens = nextLine( lines ).split( /[\s]+/ );
readFrameData( tokens, i * frameTime, root, list );
}
return list;
}
/*
Recursively reads data from a single frame into the bone hierarchy.
The passed bone hierarchy has to be structured in the same order as the BVH file.
keyframe data is stored in bone.frames.
- data: splitted string array (frame values), values are shift()ed so
this should be empty after parsing the whole hierarchy.
- frameTime: playback time for this keyframe.
- bone: the bone to read frame data from.
*/
function readFrameData( data, frameTime, bone ) {
// end sites have no motion data
if ( bone.type === "ENDSITE" ) {
return;
}
// add keyframe
var keyframe = {
time: frameTime,
position: { x: 0, y: 0, z: 0 },
rotation: new THREE.Quaternion()
};
bone.frames.push( keyframe );
var quat = new THREE.Quaternion();
var vx = new THREE.Vector3( 1, 0, 0 );
var vy = new THREE.Vector3( 0, 1, 0 );
var vz = new THREE.Vector3( 0, 0, 1 );
// parse values for each channel in node
for ( var i = 0; i < bone.channels.length; ++ i ) {
switch ( bone.channels[ i ] ) {
case "Xposition":
keyframe.position.x = parseFloat( data.shift().trim() );
break;
case "Yposition":
keyframe.position.y = parseFloat( data.shift().trim() );
break;
case "Zposition":
keyframe.position.z = parseFloat( data.shift().trim() );
break;
case "Xrotation":
quat.setFromAxisAngle( vx, parseFloat( data.shift().trim() ) * Math.PI / 180 );
keyframe.rotation.multiply( quat );
break;
case "Yrotation":
quat.setFromAxisAngle( vy, parseFloat( data.shift().trim() ) * Math.PI / 180 );
keyframe.rotation.multiply( quat );
break;
case "Zrotation":
quat.setFromAxisAngle( vz, parseFloat( data.shift().trim() ) * Math.PI / 180 );
keyframe.rotation.multiply( quat );
break;
default:
throw "invalid channel type";
}
}
// parse child nodes
for ( var i = 0; i < bone.children.length; ++ i ) {
readFrameData( data, frameTime, bone.children[ i ] );
}
}
/*
Recursively parses the HIERACHY section of the BVH file
- lines: all lines of the file. lines are consumed as we go along.
- firstline: line containing the node type and name e.g. "JOINT hip"
- list: collects a flat list of nodes
returns: a BVH node including children
*/
function readNode( lines, firstline, list ) {
var node = { name: "", type: "", frames: [] };
list.push( node );
// parse node type and name.
var tokens = firstline.split( /[\s]+/ );
if ( tokens[ 0 ].toUpperCase() === "END" && tokens[ 1 ].toUpperCase() === "SITE" ) {
node.type = "ENDSITE";
node.name = "ENDSITE"; // bvh end sites have no name
} else {
node.name = tokens[ 1 ];
node.type = tokens[ 0 ].toUpperCase();
}
if ( nextLine( lines ) != "{" ) {
throw "Expected opening { after type & name";
}
// parse OFFSET
tokens = nextLine( lines ).split( /[\s]+/ );
if ( tokens[ 0 ] !== "OFFSET" ) {
throw "Expected OFFSET, but got: " + tokens[ 0 ];
}
if ( tokens.length != 4 ) {
throw "OFFSET: Invalid number of values";
}
var offset = {
x: parseFloat( tokens[ 1 ] ),
y: parseFloat( tokens[ 2 ] ),
z: parseFloat( tokens[ 3 ] )
};
if ( isNaN( offset.x ) || isNaN( offset.y ) || isNaN( offset.z ) ) {
throw "OFFSET: Invalid values";
}
node.offset = offset;
// parse CHANNELS definitions
if ( node.type != "ENDSITE" ) {
tokens = nextLine( lines ).split( /[\s]+/ );
if ( tokens[ 0 ] != "CHANNELS" ) {
throw "Expected CHANNELS definition";
}
var numChannels = parseInt( tokens[ 1 ] );
node.channels = tokens.splice( 2, numChannels );
node.children = [];
}
// read children
while ( true ) {
var line = nextLine( lines );
if ( line === "}" ) {
return node;
} else {
node.children.push( readNode( lines, line, list ) );
}
}
}
/*
recursively converts the internal bvh node structure to a THREE.Bone hierarchy
source: the bvh root node
list: pass an empty array, collects a flat list of all converted THREE.Bones
returns the root THREE.Bone
*/
function toTHREEBone( source, list ) {
var bone = new THREE.Bone();
list.push( bone );
bone.position.add( source.offset );
bone.name = source.name;
if ( source.type != "ENDSITE" ) {
for ( var i = 0; i < source.children.length; ++ i ) {
bone.add( toTHREEBone( source.children[ i ], list ) );
}
}
return bone;
}
/*
builds a THREE.AnimationClip from the keyframe data saved in each bone.
bone: bvh root node
returns: a THREE.AnimationClip containing position and quaternion tracks
*/
function toTHREEAnimation( bones ) {
var tracks = [];
// create a position and quaternion animation track for each node
for ( var i = 0; i < bones.length; ++ i ) {
var bone = bones[ i ];
if ( bone.type == "ENDSITE" )
continue;
// track data
var times = [];
var positions = [];
var rotations = [];
for ( var j = 0; j < bone.frames.length; ++ j ) {
var frame = bone.frames[ j ];
times.push( frame.time );
// the animation system animates the position property,
// so we have to add the joint offset to all values
positions.push( frame.position.x + bone.offset.x );
positions.push( frame.position.y + bone.offset.y );
positions.push( frame.position.z + bone.offset.z );
rotations.push( frame.rotation.x );
rotations.push( frame.rotation.y );
rotations.push( frame.rotation.z );
rotations.push( frame.rotation.w );
}
if ( scope.animateBonePositions ) {
tracks.push( new THREE.VectorKeyframeTrack(
".bones[" + bone.name + "].position", times, positions ) );
}
if ( scope.animateBoneRotations ) {
tracks.push( new THREE.QuaternionKeyframeTrack(
".bones[" + bone.name + "].quaternion", times, rotations ) );
}
}
return new THREE.AnimationClip( "animation", - 1, tracks );
}
/*
returns the next non-empty line in lines
*/
function nextLine( lines ) {
var line;
// skip empty lines
while ( ( line = lines.shift().trim() ).length === 0 ) { }
return line;
}
var scope = this;
// convert buffer to ASCII string
var text = "";
var raw = new Uint8Array( buffer );
for ( var i = 0; i < raw.length; ++ i ) {
text += String.fromCharCode( raw[ i ] );
}
var lines = text.split( /[\r\n]+/g );
var bones = readBvh( lines );
var threeBones = [];
toTHREEBone( bones[ 0 ], threeBones );
var threeClip = toTHREEAnimation( bones );
return {
skeleton: new THREE.Skeleton( threeBones ),
clip: threeClip
};
}
};