add test on rotation angle before giving it to aladin lite: https://github.com/cds-astro/aladin-lite/issues/330

examples/al-displayJPG.html

@@ -23,6 +23,9 @@ Image Opacity: <br/> <input id="slider" type="range" value=1 min=0 max=1 step=0.
         aladin = A.aladin('#aladin-lite-div', {target: "0 0", cooFrame: "gal"});
         
         var callback = function(ra, dec, fov) {
+            aladin.gotoRaDec(ra, dec)
+            aladin.setFov(fov)
+
             A.catalogFromSimbad( {ra: ra, dec: dec} , 1 , {shape: 'circle', color: '#5d5', onClick: 'showTable'}, (cat) => {
                 aladin.addCatalog(cat)
             });
@@ -37,16 +40,14 @@ Image Opacity: <br/> <input id="slider" type="range" value=1 min=0 max=1 step=0.
         aladin.setBaseImageLayer('P/Mellinger/color');
 
         //let fits = aladin.displayFITS('http://goldmine.mib.infn.it/data//B/fits/A04_VC1316_ooooog.fits', 'overlay');
-        let jpg = aladin.displayJPG(
+        aladin.setOverlayImageLayer(A.image(
             // the JPG to transform to HiPS
-            'http://goldmine.mib.infn.it/data//B/fits/A04_VC1316_ooooog.fits',
+            'https://www.astropix.org/archive/esahubble/potm2602b/esahubble_potm2602b_1024.jpg',
             // no options
             {
-                transparency: 1.0,
+                successCallback: callback
             },
-            // A callback fn once the overlay is set
-            callback
-        );
+        ));
 
         $('input[name=survey]').change(function() {
             let surveyName = $(this).val();

src/js/Aladin.js

@@ -2183,6 +2183,10 @@ export let Aladin = (function () {
      * view in the counter clockwise order (or towards the east)
      */
     Aladin.prototype.setRotation = function (rotation) {
+        if (!rotation) {
+            console.warn("Rotation angle is not valid:", rotation)
+            return;
+        }
         this.view.setRotation(rotation);
     };