upscaleComp.jsx

/*
This script is used to rescale composition with all its contents
preserving keyframes etc 
Also preserves its scale in parent comp

Nik Ska, 2014
CC-BY-SA  
*/

#script "Rescale precomp";

var ddRescale = this;

ddRescale.buildGUI = function(thisObj){
    thisObj.w = (thisObj instanceof Panel) ? thisObj : new Window("palette", "Rescale precomp", undefined, {resizeable:true});
    thisObj.w.alignChildren = ['left', 'top']

    var g = thisObj.w.add("group{orientation:'column', alignChildren: ['left', 'top']}");
    g.add("staticText", undefined, "New scale");

    var scaleLine = g.add("group{orientation:'row', alignChildren: ['left', 'top']}");
    var scaleText = scaleLine.add("editText", undefined, "0");
    scaleText.size = [60, 30];
    var goBttn = scaleLine.add("button", undefined, "Go!");
    goBttn.size = [30,30];
    scaleText.text = 100;
    
    scaleText.onChanging = function(){
        preFilter = /[+-]?([0-9\:]*)/; //this one does not allow to input anything but numbers and some symbols;
        this.text = this.text.match(preFilter)[0];
    }

    scaleText.onEnterKey = function(){
        thisObj.run(Number(scaleText.text));
    }

    goBttn.onClick = function(){
        thisObj.run(Number(scaleText.text));
    }

    if (thisObj.w instanceof Window){
        thisObj.w.center();
        thisObj.w.show();
    }
    else thisObj.w.layout.layout(true);
}

ddRescale.rescale = function(comp, scaleFactor){
    /*
    Rescales the comp completely with all its contents
    Uses a temporary null object for that
    */

    var moveVector = [comp.width, comp.height]*(scaleFactor-1)/2;
    comp.width *= scaleFactor;
    comp.height *= scaleFactor;

    //adding null for auto-rescale
    var cNull = comp.layers.addNull();
    cNull.moveToBeginning();
    //moving it to comp center
    cNull.transform.position.setValue([comp.width/2, comp.height/2]);

    for(var l = 2; l <= comp.layers.length; l++){
        //now parent each parentless layer to it
        var layer = comp.layers[l];
        if(!layer.hasParent) layer.parent = cNull;

        if(layer.canSetCollapseTransformation) layer.collapseTransformation = true;

        //now move
        if(layer.transform.position.isTimeVarying == false) layer.transform.position.setValue(layer.transform.position.value + moveVector);
        else{
            //if we have keyframes
            var pos = layer.transform.position;
            for(var k = 1; k <= pos.numKeys; k++){
                pos.setValueAtKey(k, pos.keyValue(k) + moveVector)
            }
        }

        if(layer.source instanceof CompItem){
            ddRescale.rescale(layer.source, scaleFactor)
        }
    }
    cNull.transform.scale.setValue([100,100,100]*scaleFactor);
    cNull.remove();
    
        
}

ddRescale.run = function(newScale){
    var activeComp = app.project.activeItem;
    if(activeComp && activeComp instanceof CompItem){
        app.beginUndoGroup("Upscaling comp");
        var sel = activeComp.selectedLayers;

        var factor = 100;
        if(!isNaN(newScale)) factor = newScale/100;

        if(sel.length > 0){
            for(var s = 0; s < sel.length; s++){
                if(sel[s].source instanceof CompItem){
                    //scale precomp contents up
                    this.rescale(sel[s].source, factor);  
                    
                    //and precomp itself down          
                    sel[s].transform.scale.setValue((1/factor)*sel[s].transform.scale.value);
                    }
                }
            }
        else{
            this.rescale(activeComp, factor)
        }
        app.endUndoGroup();
    }
}


ddRescale.buildGUI(ddRescale);