【AE表达式】表达式值和原值切换

https://www.bilibili.com/video/BV1cf4y1c7Js/

function expressionFormula(){
    return [0,0];}

t = 0.2;
mode = 1;
if (thisLayer.marker.numKeys==0){value;}
else{
        n = thisLayer.marker.nearestKey(time).index;
        if(thisLayer.marker.key(n).time > time && n>1){n--;}
        markerTime = thisLayer.marker.key(n).time;
        markerDuration = thisLayer.marker.key(n).duration;
        expressionValue = expressionFormula();
        if(mode == 0){
            if(time>=markerTime && time<markerTime+markerDuration){expressionValue;}
            else value;
        }
        else if(mode == 1){
            if(time>=markerTime && time<markerTime+markerDuration){
                num = 0;
                t1 = markerTime+t;
                t2 = markerTime+markerDuration-t;
                if (time<t1){num = linear(time,markerTime,t1,0,1);}
                else if (time>=t2){num = linear(time,t2,markerTime+markerDuration,1,0);}
                else num = 1;
                //expressionValue*num+value*(1-num);
                ease(num,0,1,value,expressionValue);
            }
            else value;
        }
}