From db8fd8da01fd64d46bb56ed4157cd9f083f59883 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Tue, 17 Mar 2020 06:57:16 +0100
Subject: [PATCH] fixed the uniform scaling option

---
 CHANGELOG.md            | 13 ++++-----
 src/controls.actions.js | 60 +++++++++++++++++++++++++++--------------
 2 files changed, 47 insertions(+), 26 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 40455b66ed1..8fd8cc27808 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,12 +2,13 @@
 
 ## [4.0.0-beta.8]
 
-- fix(svg_parsers): Add support for empty <style/> tags [#6169](https://github.com/fabricjs/fabric.js/pull/)
-- fix(SVG_export, text): Check font faces markup for objects within groups [#6195](https://github.com/fabricjs/fabric.js/pull/)
-- feat(animation): Extend fabric.util.animate animating colors and other properties[#6191](https://github.com/fabricjs/fabric.js/pull/)
-- fix(svg_export): remove extra space from svg export [#6209](https://github.com/fabricjs/fabric.js/pull/)
-- fix(svg_import): ISSUE-6170 do not try to create missing clippath [#6210](https://github.com/fabricjs/fabric.js/pull/)
-- fix(fabric.Object) Adding existence check for this.canvas on object stacking mixins [#6207](https://github.com/fabricjs/fabric.js/pull/)
+- fix(fabric.Object): fix activeSelection toDataURL canvas restore [#6216](https://github.com/fabricjs/fabric.js/pull/6216)
+- fix(svg_parsers): Add support for empty <style/> tags [#6169](https://github.com/fabricjs/fabric.js/pull/6169)
+- fix(SVG_export, text): Check font faces markup for objects within groups [#6195](https://github.com/fabricjs/fabric.js/pull/6195)
+- feat(animation): Extend fabric.util.animate animating colors and other properties[#6191](https://github.com/fabricjs/fabric.js/pull/6191)
+- fix(svg_export): remove extra space from svg export [#6209](https://github.com/fabricjs/fabric.js/pull/6209)
+- fix(svg_import): ISSUE-6170 do not try to create missing clippath [#6210](https://github.com/fabricjs/fabric.js/pull/6210)
+- fix(fabric.Object) Adding existence check for this.canvas on object stacking mixins [#6207](https://github.com/fabricjs/fabric.js/pull/6207)
 
 ## [4.0.0-beta.7]
 
diff --git a/src/controls.actions.js b/src/controls.actions.js
index 4b12c9dd12b..4e9ad1d44f3 100644
--- a/src/controls.actions.js
+++ b/src/controls.actions.js
@@ -21,19 +21,41 @@
     target.fire(eventName, options);
   }
 
-  function scaleCursorStyleHandler(eventData, corner, fabricObject) {
-    var canvas = fabricObject.canvas, uniScaleKey = canvas.uniScaleKey, notAllowed = 'not-allowed',
-        uniformIsToggled = eventData[uniScaleKey],
-        scaleIsProportional = (canvas.uniformScaling && !uniformIsToggled) ||
-        (!canvas.uniformScaling && uniformIsToggled);
+  function scaleIsProportional(eventData, fabricObject) {
+    var canvas = fabricObject.canvas, uniScaleKey = canvas.uniScaleKey,
+        uniformIsToggled = eventData[uniScaleKey];
+    return (canvas.uniformScaling && !uniformIsToggled) ||
+    (!canvas.uniformScaling && uniformIsToggled);
+  }
 
-    if (fabricObject.lockScalingX && fabricObject.lockScalingY) {
-      return notAllowed;
+  function scalingIsForbidden(fabricObject, by, scaleProportionally) {
+    var lockX = fabricObject.lockScalingX, lockY = fabricObject.lockScalingY;
+    if (lockX && lockY) {
+      return true;
     }
-    if (corner.x !== 0 && fabricObject.lockScalingX && scaleIsProportional) {
-      return notAllowed;
+    if (!by && (lockX || lockY) && scaleProportionally) {
+      return true;
+    }
+    if (lockX && by === 'x') {
+      return true;
+    }
+    if (lockY && by === 'y') {
+      return true;
+    }
+    return false;
+  }
+
+  function scaleCursorStyleHandler(eventData, corner, fabricObject) {
+    var notAllowed = 'not-allowed',
+        scaleProportionally = scaleIsProportional(eventData, fabricObject),
+        by = '';
+    if (corner.x !== 0 && corner.y === 0) {
+      by = 'x';
+    }
+    else if (corner.x === 0 && corner.y !== 0) {
+      by = 'y';
     }
-    if (corner.y !== 0 && fabricObject.lockScalingY && scaleIsProportional) {
+    if (scalingIsForbidden(fabricObject, by, scaleProportionally)) {
       return notAllowed;
     }
     var n = findCornerQuadrant(fabricObject, corner);
@@ -341,15 +363,12 @@
   function scaleObject(eventData, transform, x, y, options) {
     options = options || {};
     var target = transform.target,
-        uniScaleKey = target.canvas.uniScaleKey, isUniScalePressed = eventData[uniScaleKey],
         lockScalingX = target.lockScalingX, lockScalingY = target.lockScalingY,
-        by = options.by, newPoint, scaleX, scaleY, dim;
-
-    if (!isUniScalePressed && (lockScalingX || lockScalingY)) {
-      return false;
-    }
+        by = options.by, newPoint, scaleX, scaleY, dim,
+        scaleProportionally = scaleIsProportional(eventData, target),
+        forbidScaling = scalingIsForbidden(target, by, scaleProportionally);
 
-    if (isUniScalePressed && lockScalingX && lockScalingY) {
+    if (forbidScaling) {
       return false;
     }
 
@@ -357,7 +376,7 @@
     newPoint = getLocalPoint(target, transform.originX, transform.originY, x, y);
 
     // missing detection of flip and logic to switch the origin
-    if (!isUniScalePressed && !by) {
+    if (scaleProportionally && !by) {
       // uniform scaling
       var distance = Math.abs(newPoint.x) + Math.abs(newPoint.y),
           original = transform.original,
@@ -379,10 +398,11 @@
     // minScale is taken are in the setter.
     var oldScaleX = target.scaleX, oldScaleY = target.scaleY;
     if (!by) {
-      target.set('scaleX', scaleX);
-      target.set('scaleY', scaleY);
+      !lockScalingX && target.set('scaleX', scaleX);
+      !lockScalingY && target.set('scaleY', scaleY);
     }
     else {
+      // forbidden cases already handled on top here.
       by === 'x' && target.set('scaleX', scaleX);
       by === 'y' && target.set('scaleY', scaleY);
     }