Fit Layer To Canvas - Photoshop Script

Fit Layer To Canvas.jsx

// FIT LAYER TO CANVAS
// via https://forums.adobe.com/message/5413957#5413957
var maintainAspectRatio;// set to true to keep aspect ratio  
if(app.documents.length>0){  
    app.activeDocument.suspendHistory ('Fit Layer to Canvas', 'FitLayerToCanvas('+maintainAspectRatio+')');  
}  
function FitLayerToCanvas( keepAspect ){// keepAspect:Boolean - optional. Default to false  
    var doc = app.activeDocument;  
    var layer = doc.activeLayer;  
    // do nothing if layer is background or locked  
    if(layer.isBackgroundLayer || layer.allLocked || layer.pixelsLocked  
                            || layer.positionLocked || layer.transparentPixelsLocked ) return;  
    // do nothing if layer is not normal artLayer or Smart Object  
    if( layer.kind != LayerKind.NORMAL && layer.kind != LayerKind.SMARTOBJECT) return;  
    // store the ruler  
    var defaultRulerUnits = app.preferences.rulerUnits;  
    app.preferences.rulerUnits = Units.PIXELS;  
      
    var width = doc.width.as('px');  
    var height =doc.height.as('px');  
    var bounds = app.activeDocument.activeLayer.bounds;  
    var layerWidth = bounds[2].as('px')-bounds[0].as('px');  
    var layerHeight = bounds[3].as('px')-bounds[1].as('px');  
          
    // move the layer so top left corner matches canvas top left corner  
    layer.translate(new UnitValue(0-layer.bounds[0].as('px'),'px'), new UnitValue(0-layer.bounds[1].as('px'),'px'));  
    if( !keepAspect ){  
        // scale the layer to match canvas  
        layer.resize( (width/layerWidth)*100,(height/layerHeight)*100,AnchorPosition.TOPLEFT);  
    }else{  
        var layerRatio = layerWidth / layerHeight;  
        var newWidth = width;  
        var newHeight = ((1.0 * width) / layerRatio);  
        if (newHeight >= height) {  
            newWidth = layerRatio * height;  
            newHeight = height;  
        }  
        var resizePercent = newWidth/layerWidth*100;  
        app.activeDocument.activeLayer.resize(resizePercent,resizePercent,AnchorPosition.TOPLEFT);  
    }  
    // restore the ruler  
    app.preferences.rulerUnits = defaultRulerUnits;  
}  

Thank you jawinn! Really useful script. But it doesn't fit layer proportionally. I fixed it:

// FIT LAYER TO CANVAS
// via https://forums.adobe.com/message/5413957#5413957
var maintainAspectRatio = true; // set to true to keep aspect ratio

if (app.documents.length > 0) {
app.activeDocument.suspendHistory('Fit Layer to Canvas', 'FitLayerToCanvas(' + maintainAspectRatio + ')');
}

function FitLayerToCanvas(keepAspect) {
// keepAspect: Boolean - optional. Default to false
var doc = app.activeDocument;
var layer = doc.activeLayer;

// do nothing if layer is background or locked
if (layer.isBackgroundLayer || layer.allLocked || layer.pixelsLocked || layer.positionLocked || layer.transparentPixelsLocked) return;

// do nothing if layer is not a normal artLayer or Smart Object
if (layer.kind != LayerKind.NORMAL && layer.kind != LayerKind.SMARTOBJECT) return;

// store the ruler
var defaultRulerUnits = app.preferences.rulerUnits;
app.preferences.rulerUnits = Units.PIXELS;

var width = doc.width.as('px');
var height = doc.height.as('px');
var bounds = app.activeDocument.activeLayer.bounds;
var layerWidth = bounds[2].as('px') - bounds[0].as('px');
var layerHeight = bounds[3].as('px') - bounds[1].as('px');

// move the layer so the top-left corner matches the canvas top-left corner
layer.translate(new UnitValue(0 - bounds[0].as('px'), 'px'), new UnitValue(0 - bounds[1].as('px'), 'px'));

if (keepAspect) {
var layerRatio = layerWidth / layerHeight;
var canvasRatio = width / height;

if (layerRatio > canvasRatio) {
  var newWidth = width;
  var newHeight = newWidth / layerRatio;
} else {
  var newHeight = height;
  var newWidth = newHeight * layerRatio;
}

var resizePercent = (newWidth / layerWidth) * 100;
app.activeDocument.activeLayer.resize(resizePercent, resizePercent, AnchorPosition.TOPLEFT);

} else {
// scale the layer to match the canvas
layer.resize((width / layerWidth) * 100, (height / layerHeight) * 100, AnchorPosition.TOPLEFT);
}

// restore the ruler
app.preferences.rulerUnits = defaultRulerUnits;
}