** * Returns `true` if the given keyframe track settings hold Bezier tangent data. * * @param {?Object} settings - The settings of a keyframe track. * @return {boolean} Whether both tangent arrays are defined or not. */ function hasTangents( settings ) { return settings !== undefined && settings.inTangents !== undefined && settings.outTangents !== undefined; } /** * Returns an array by which times and values can be sorted. * * @param {Array} times - The keyframe time values. * @return {Array} The array. */ function getKeyframeOrder( times ) { function compareTime( i, j ) { return times[ i ] - times[ j ]; } const n = times.length; const result = new Array( n ); for ( let i = 0; i !== n; ++ i ) result[ i ] = i; result.sort( compareTime ); return result; } /** * Sorts the given array by the previously computed order via `getKeyframeOrder()`. * * @param {Array} values - The values to sort. * @param {number} stride - The stride. * @param {Array} order - The sort order. * @return {Array} The sorted values. */ function sortedArray( values, stride, order ) { const nValues = values.length; const result = new values.constructor( nValues ); for ( let i = 0, dstOffset = 0; dstOffset !== nValues; ++ i ) { const srcOffset = order[ i ] * stride; for ( let j = 0; j !== stride; ++ j ) { result[ dstOffset ++ ] = values[ srcOffset + j ]; } } return result; } /** * Used for parsing AOS keyframe formats. * * @param {Array} jsonKeys - A list of JSON keyframes. * @param {Array} times - This array will be filled with keyframe times by this function. * @param {Array} values - This array will be filled with keyframe values by this function. * @param {string} valuePropertyName - The name of the property to use. */ function flattenJSON( jsonKeys, times, values, valuePropertyName ) { let i = 1, key = jsonKeys[ 0 ]; while ( key !== undefined && key[ valuePropertyName ] === undefined ) { key = jsonKeys[ i ++ ]; } if ( key === undefined ) return; // no data let 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( ...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 ); } } /** * Creates a new clip, containing only the segment of the original clip between the given frames. * * @param {AnimationClip} sourceClip - The values to sort. * @param {string} name - The name of the clip. * @param {number} startFrame - The start frame. * @param {number} endFrame - The end frame. * @param {number} [fps=30] - The FPS. * @return {AnimationClip} The new sub clip. */ function subclip( sourceClip, name, startFrame, endFrame, fps = 30 ) { const clip = sourceClip.clone(); clip.name = name; const tracks = []; for ( let i = 0; i < clip.tracks.length; ++ i ) { const track = clip.tracks[ i ]; const valueSize = track.getValueSize(); const times = []; const values = []; for ( let j = 0; j < track.times.length; ++ j ) { const frame = track.times[ j ] * fps; if ( frame < startFrame || frame >= endFrame ) continue; times.push( track.times[ j ] ); for ( let k = 0; k < valueSize; ++ k ) { values.push( track.values[ j * valueSize + k ] ); } } if ( times.length === 0 ) continue; track.times = convertArray( times, track.times.constructor ); track.values = convertArray( values, track.values.constructor ); tracks.push( track ); } clip.tracks = tracks; // find minimum .times value across all tracks in the trimmed clip let minStartTime = Infinity; for ( let i = 0; i < clip.tracks.length; ++ i ) { if ( minStartTime > clip.tracks[ i ].times[ 0 ] ) { minStartTime = clip.tracks[ i ].times[ 0 ]; } } // shift all tracks such that clip begins at t=0 for ( let i = 0; i < clip.tracks.length; ++ i ) { clip.tracks[ i ].shift( -1 * minStartTime ); } clip.resetDuration(); return clip; } /** * Converts the keyframes of the given animation clip to an additive format. * * @param {AnimationClip} targetClip - The clip to make additive. * @param {number} [referenceFrame=0] - The reference frame. * @param {AnimationClip} [refer