P5-2706 add getCropRatio function

dist/image-editor.js

@@ -1363,6 +1363,20 @@ function ImageEditor(canvasId, args) {
         return this;
     };
 
+    this.getCropRatio = function () {
+        var image = _canvas.getImage();
+        var cropData = _canvas.getImageData().getCropData();
+        if (!cropData) {
+            return false;
+        }
+        var scaledImageWidth = image.width * image.scaleX;
+        var scaledImageHeight = image.height * image.scaleY;
+        var ratioWidth = Math.round(cropData.viewportWidth / scaledImageWidth * 100) / 100;
+        var ratioHeight = Math.round(cropData.viewportHeight / scaledImageHeight * 100) / 100;
+
+        return {width: ratioWidth, height: ratioHeight};
+    };
+
     /**
      * @param  {string|object} key
      * @param  {object} defaultValue

src/ImageEditor.js

@@ -125,6 +125,20 @@ function ImageEditor(canvasId, args) {
         return this;
     };
 
+    this.getCropRatio = function () {
+        var image = _canvas.getImage();
+        var cropData = _canvas.getImageData().getCropData();
+        if (!cropData) {
+            return false;
+        }
+        var scaledImageWidth = image.width * image.scaleX;
+        var scaledImageHeight = image.height * image.scaleY;
+        var ratioWidth = Math.round(cropData.viewportWidth / scaledImageWidth * 100) / 100;
+        var ratioHeight = Math.round(cropData.viewportHeight / scaledImageHeight * 100) / 100;
+
+        return {width: ratioWidth, height: ratioHeight};
+    };
+
     /**
      * @param  {string|object} key
      * @param  {object} defaultValue