From: Vincent Vanwaelscappel <vincent@cubedesigners.com>
Date: Wed, 8 Mar 2023 17:03:20 +0000 (+0100)
Subject: wait #5778 @1.5
X-Git-Url: http://git.cubedesigners.com/?a=commitdiff_plain;h=32063d388e27c48074011a2870ef6f95d8974c67;p=fluidbook-toolbox.git

wait #5778 @1.5
---

diff --git a/resources/linkeditor/js/linkeditor.zoom.js b/resources/linkeditor/js/linkeditor.zoom.js
index e93c47522..54f88cf95 100644
--- a/resources/linkeditor/js/linkeditor.zoom.js
+++ b/resources/linkeditor/js/linkeditor.zoom.js
@@ -14,6 +14,8 @@ LinkeditorZoom.prototype = {
             $("#linkeditor-main").on('wheel', function (e) {
                 var step = $this.zoom >= 1 ? 0.25 : 0.1;
                 $this.linkeditor.setMouseCoordinates(e);
+                let cursorPositionOnFluidbookBeforeZoom = $this.getFluidbookPositionOfCursor();
+
                 let delta = e.originalEvent.deltaY;
                 if (delta === 0) {
                     return true;
@@ -21,18 +23,23 @@ LinkeditorZoom.prototype = {
                 e.stopPropagation();
                 e.stopImmediatePropagation();
                 e.preventDefault();
-                if (delta < 0) {
-                    if ($this.setZoom($this.zoom + step)) {
-                        $this.moveZoom(e);
-                    }
-                } else {
-                    $this.setZoom($this.zoom - step);
+
+                if ($this.setZoom($this.zoom + step * (delta > 0 ? -1 : 1))) {
+                    $this.moveZoomAfterWheelZoom(cursorPositionOnFluidbookBeforeZoom);
                 }
+
                 return false;
             });
         }
     },
 
+    getFluidbookPositionOfCursor: function () {
+        let rect = $("#linkeditor-fluidbook").get(0).getBoundingClientRect();
+        let lx = (this.linkeditor.mx - rect.x) / rect.width;
+        let ly = (this.linkeditor.my - rect.y) / rect.height;
+        return {x: lx, y: ly, width: rect.width, height: rect.height};
+    },
+
     mouseUp: function () {
         if (!this.zoomdragging) {
             return;
@@ -64,11 +71,15 @@ LinkeditorZoom.prototype = {
         this.linkeditor.rulers.updateRulers();
     },
 
-    moveZoom: function (e) {
-        let rect = $("#linkeditor-zoom").get(0).getBoundingClientRect();
-        let lx = (e.originalEvent.pageX - rect.x) / rect.width;
-        let ly = (e.originalEvent.pageY - rect.y) / rect.height;
-        $("#linkeditor-canvas").scrollTo({left: this.linkeditor.utils.pct(lx), top: this.linkeditor.utils.pct(ly)});
+    moveZoomAfterWheelZoom: function (initialPosition) {
+        let currentPosition = this.getFluidbookPositionOfCursor();
+        var dx = (initialPosition.x - currentPosition.x) * currentPosition.width;
+        var sx = $("#linkeditor-canvas").scrollLeft() + dx;
+
+        var dy = (initialPosition.y - currentPosition.y) * currentPosition.height;
+        var sy = $("#linkeditor-canvas").scrollTop() + dy;
+
+        $("#linkeditor-canvas").scrollTo({left: sx, top: sy});
         this.linkeditor.rulers.updateRulers();
     },