three
Version:
JavaScript 3D library
160 lines (90 loc) • 3.12 kB
JavaScript
/**
* @author tschw
* @author Ben Houston / http://clara.io/
* @author David Sarno / http://lighthaus.us/
*/
THREE.AnimationUtils = {
// same as Array.prototype.slice, but also works on typed arrays
arraySlice: function( array, from, to ) {
if ( THREE.AnimationUtils.isTypedArray( array ) ) {
return new array.constructor( array.subarray( from, to ) );
}
return array.slice( from, to );
},
// converts an array to a specific type
convertArray: function( array, type, forceClone ) {
if ( ! array || // let 'undefined' and 'null' pass
! forceClone && array.constructor === type ) return array;
if ( typeof type.BYTES_PER_ELEMENT === 'number' ) {
return new type( array ); // create typed array
}
return Array.prototype.slice.call( array ); // create Array
},
isTypedArray: function( object ) {
return ArrayBuffer.isView( object ) &&
! ( object instanceof DataView );
},
// returns an array by which times and values can be sorted
getKeyframeOrder: function( times ) {
function compareTime( i, j ) {
return times[ i ] - times[ j ];
}
var n = times.length;
var result = new Array( n );
for ( var i = 0; i !== n; ++ i ) result[ i ] = i;
result.sort( compareTime );
return result;
},
// uses the array previously returned by 'getKeyframeOrder' to sort data
sortedArray: function( values, stride, order ) {
var nValues = values.length;
var result = new values.constructor( nValues );
for ( var i = 0, dstOffset = 0; dstOffset !== nValues; ++ i ) {
var srcOffset = order[ i ] * stride;
for ( var j = 0; j !== stride; ++ j ) {
result[ dstOffset ++ ] = values[ srcOffset + j ];
}
}
return result;
},
// function for parsing AOS keyframe formats
flattenJSON: function( jsonKeys, times, values, valuePropertyName ) {
var i = 1, key = jsonKeys[ 0 ];
while ( key !== undefined && key[ valuePropertyName ] === undefined ) {
key = jsonKeys[ i ++ ];
}
if ( key === undefined ) return; // no data
var value = key[ valuePropertyName ];
if ( value === undefined ) return; // no data
if ( Array.isArray( value ) ) {
do {
value = key[ valuePropertyName ];
if ( value !== undefined ) {
times.push( key.time );
values.push.apply( values, value ); // push all elements
}
key = jsonKeys[ i ++ ];
} while ( key !== undefined );
} else if ( value.toArray !== undefined ) {
// ...assume THREE.Math-ish
do {
value = key[ valuePropertyName ];
if ( value !== undefined ) {
times.push( key.time );
value.toArray( values, values.length );
}
key = jsonKeys[ i ++ ];
} while ( key !== undefined );
} else {
// otherwise push as-is
do {
value = key[ valuePropertyName ];
if ( value !== undefined ) {
times.push( key.time );
values.push( value );
}
key = jsonKeys[ i ++ ];
} while ( key !== undefined );
}
}
};