source: other-projects/playing-in-the-street/summer-2013/trunk/Playing-in-the-Street-WPF/Content/Web/mrdoob-three.js-4862f5f/src/extras/animation/AnimationMorphTarget.js@ 28897

/**
 * @author mikael emtinger / http://gomo.se/
 */

THREE.AnimationMorphTarget = function( root, data ) {

    this.root = root;
    this.data = THREE.AnimationHandler.get( data );
    this.hierarchy = THREE.AnimationHandler.parse( root );
    this.currentTime = 0;
    this.timeScale = 1;
    this.isPlaying = false;
    this.isPaused = true;
    this.loop = true;
    this.influence = 1;
}

/*
 * Play
 */

THREE.AnimationMorphTarget.prototype.play = function( loop, startTimeMS ) {

    if( !this.isPlaying ) {

        this.isPlaying = true;
        this.loop = loop !== undefined ? loop : true;
        this.currentTime = startTimeMS !== undefined ? startTimeMS : 0;


        // reset key cache

        for ( var h = 0; h < this.hierarchy.length; h++ ) {

            if ( this.hierarchy[ h ].animationCache === undefined ) {

                this.hierarchy[ h ].animationCache = {};
                this.hierarchy[ h ].animationCache.prevKey = 0;
                this.hierarchy[ h ].animationCache.nextKey = 0;
            }

            this.hierarchy[ h ].animationCache.prevKey = this.data.hierarchy[ h ].keys[ 0 ];
            this.hierarchy[ h ].animationCache.nextKey = this.data.hierarchy[ h ].keys[ 1 ];
        }

        this.update( 0 );
    }

    this.isPaused = false;
    THREE.AnimationHandler.addToUpdate( this );
}


/*
 * Pause
 */

THREE.AnimationMorphTarget.prototype.pause = function() {

    if( this.isPaused ) {
        
        THREE.AnimationHandler.addToUpdate( this );
        
    } else {
        
        THREE.AnimationHandler.removeFromUpdate( this );
        
    }
    
    this.isPaused = !this.isPaused;
}


/*
 * Stop
 */

THREE.AnimationMorphTarget.prototype.stop = function() {

    this.isPlaying = false;
    this.isPaused  = false;
    
    THREE.AnimationHandler.removeFromUpdate( this );
    
    
    // reset JIT matrix and remove cache
    
    for ( var h = 0; h < this.hierarchy.length; h++ ) {
        
        if ( this.hierarchy[ h ].animationCache !== undefined ) {
            
            delete this.hierarchy[ h ].animationCache;  
        }

    }

}


/*
 * Update
 */

THREE.AnimationMorphTarget.prototype.update = function( deltaTimeMS ) {

    // early out

    if( !this.isPlaying ) return;


    // vars

    var scale;
    var vector;
    var prevXYZ, nextXYZ;
    var prevKey, nextKey;
    var object;
    var animationCache;
    var currentTime, unloopedCurrentTime;
    

    // update time
    
    this.currentTime += deltaTimeMS * this.timeScale;

    unloopedCurrentTime = this.currentTime;
    currentTime         = this.currentTime = this.currentTime % this.data.length;


    // update

    for ( var h = 0, hl = this.hierarchy.length; h < hl; h++ ) {

        object = this.hierarchy[ h ];
        animationCache = object.animationCache;


        // get keys

        prevKey = animationCache.prevKey;
        nextKey = animationCache.nextKey;


        // switch keys?

        if ( nextKey.time <= unloopedCurrentTime ) {

            // did we loop?

            if ( currentTime < unloopedCurrentTime ) {

                if ( this.loop ) {

                    prevKey = this.data.hierarchy[ h ].keys[ 0 ];
                    nextKey = this.data.hierarchy[ h ].keys[ 1 ];

                    while( nextKey.time < currentTime ) {

                        prevKey = nextKey;
                        nextKey = this.data.hierarchy[ h ].keys[ nextKey.index + 1 ];

                    }

                } else {

                    this.stop();
                    return;

                }

            } else {

                do {

                    prevKey = nextKey;
                    nextKey = this.data.hierarchy[ h ].keys[ nextKey.index + 1 ];

                } while( nextKey.time < currentTime )

            }

            animationCache.prevKey = prevKey;
            animationCache.nextKey = nextKey;

        }


        // calc scale and check for error

        scale = ( currentTime - prevKey.time ) / ( nextKey.time - prevKey.time );

        if ( scale < 0 || scale > 1 ) {

            console.log( "THREE.AnimationMorphTarget.update: Warning! Scale out of bounds:" + scale ); 
            scale = scale < 0 ? 0 : 1;

        }


        // interpolate
        
        var pi, pmti = prevKey.morphTargetsInfluences;
        var ni, nmti = nextKey.morphTargetsInfluences;
        var mt, i;
        
        for( mt in pmti ) {
            
            pi = pmti[ mt ];
            ni = nmti[ mt ];
            i = this.root.getMorphTargetIndexByName( mt );
            
            this.root.morphTargetInfluences[ i ] = ( pi + ( ni - pi ) * scale ) * this.influence;
        }

    }

};