From e641b0a965f3992330872a8e11d4850b94e63c5d Mon Sep 17 00:00:00 2001
From: Nick O'Leary <nick.oleary@gmail.com>
Date: Mon, 10 May 2021 21:02:54 +0100
Subject: [PATCH] Fix scaling issues when dragging nodes into scaled workspace

---
 .../editor-client/src/js/ui/palette.js          | 17 +++++++----------
 .../@node-red/editor-client/src/js/ui/view.js   | 10 +++++++---
 2 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/packages/node_modules/@node-red/editor-client/src/js/ui/palette.js b/packages/node_modules/@node-red/editor-client/src/js/ui/palette.js
index 0cb202051..09f4758f1 100755
--- a/packages/node_modules/@node-red/editor-client/src/js/ui/palette.js
+++ b/packages/node_modules/@node-red/editor-client/src/js/ui/palette.js
@@ -320,12 +320,12 @@ RED.palette = (function() {
                     var paletteNode = getPaletteNode(nt);
                     ui.originalPosition.left = paletteNode.offset().left;
                     mouseX = ui.position.left - paletteWidth + (ui.helper.width()/2) + chart.scrollLeft();
-                    mouseY = ui.position.top - paletteTop + (ui.helper.height()/2) + chart.scrollTop();
+                    mouseY = ui.position.top - paletteTop + (ui.helper.height()/2) + chart.scrollTop() + 10;
                     if (!groupTimer) {
                         groupTimer = setTimeout(function() {
-                            mouseX /= RED.view.scale();
-                            mouseY /= RED.view.scale();
-                            var group = RED.view.getGroupAtPoint(mouseX,mouseY);
+                            var mx = mouseX / RED.view.scale();
+                            var my = mouseY / RED.view.scale();
+                            var group = RED.view.getGroupAtPoint(mx,my);
                             if (group !== hoverGroup) {
                                 if (hoverGroup) {
                                     document.getElementById("group_select_"+hoverGroup.id).classList.remove("red-ui-flow-group-hovered");
@@ -357,23 +357,20 @@ RED.palette = (function() {
                                     svgRect.width = 1;
                                     svgRect.height = 1;
                                     nodes = chartSVG.getIntersectionList(svgRect,chartSVG);
-                                    mouseX /= RED.view.scale();
-                                    mouseY /= RED.view.scale();
                                 } else {
                                     // Firefox doesn't do getIntersectionList and that
                                     // makes us sad
-                                    mouseX /= RED.view.scale();
-                                    mouseY /= RED.view.scale();
                                     nodes = RED.view.getLinksAtPoint(mouseX,mouseY);
                                 }
-
+                                var mx = mouseX / RED.view.scale();
+                                var my = mouseY / RED.view.scale();
                                 for (var i=0;i<nodes.length;i++) {
                                     var node = d3.select(nodes[i]);
                                     if (node.classed('red-ui-flow-link-background') && !node.classed('red-ui-flow-link-link')) {
                                         var length = nodes[i].getTotalLength();
                                         for (var j=0;j<length;j+=10) {
                                             var p = nodes[i].getPointAtLength(j);
-                                            var d2 = ((p.x-mouseX)*(p.x-mouseX))+((p.y-mouseY)*(p.y-mouseY));
+                                            var d2 = ((p.x-mx)*(p.x-mx))+((p.y-my)*(p.y-my));
                                             if (d2 < 200 && d2 < bestDistance) {
                                                 bestDistance = d2;
                                                 bestLink = nodes[i];
diff --git a/packages/node_modules/@node-red/editor-client/src/js/ui/view.js b/packages/node_modules/@node-red/editor-client/src/js/ui/view.js
index bffc6fd85..d3c9340d8 100755
--- a/packages/node_modules/@node-red/editor-client/src/js/ui/view.js
+++ b/packages/node_modules/@node-red/editor-client/src/js/ui/view.js
@@ -1476,15 +1476,15 @@ RED.view = (function() {
                             var mouseY = node.n.y;
                             if (outer[0][0].getIntersectionList) {
                                 var svgRect = outer[0][0].createSVGRect();
-                                svgRect.x = mouseX;
-                                svgRect.y = mouseY;
+                                svgRect.x = mouseX*scaleFactor;
+                                svgRect.y = mouseY*scaleFactor;
                                 svgRect.width = 1;
                                 svgRect.height = 1;
                                 nodes = outer[0][0].getIntersectionList(svgRect, outer[0][0]);
                             } else {
                                 // Firefox doesn"t do getIntersectionList and that
                                 // makes us sad
-                                nodes = RED.view.getLinksAtPoint(mouseX,mouseY);
+                                nodes = RED.view.getLinksAtPoint(mouseX*scaleFactor,mouseY*scaleFactor);
                             }
                             for (var i=0;i<nodes.length;i++) {
                                 if (d3.select(nodes[i]).classed("red-ui-flow-link-background")) {
@@ -3445,6 +3445,7 @@ RED.view = (function() {
         }
     }
     function getGroupAt(x,y) {
+        // x,y expected to be in node-co-ordinate space
         var candidateGroups = {};
         for (var i=0;i<activeGroups.length;i++) {
             var g = activeGroups[i];
@@ -5081,6 +5082,9 @@ RED.view = (function() {
             return scaleFactor;
         },
         getLinksAtPoint: function(x,y) {
+            // x,y must be in SVG co-ordinate space
+            // if they come from a node.x/y, they will need to be scaled using
+            // scaleFactor first.
             var result = [];
             var links = outer.selectAll(".red-ui-flow-link-background")[0];
             for (var i=0;i<links.length;i++) {