From c0c67df9699315223ac90732b8870dfbe61339d8 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Sat, 14 Aug 2021 20:10:49 +0200
Subject: [PATCH 1/7] draft of the function

---
 src/util/path.js | 36 +++++++++++++++++++++++++++++++++---
 1 file changed, 33 insertions(+), 3 deletions(-)

diff --git a/src/util/path.js b/src/util/path.js
index b6479352b4c..cb90e263038 100644
--- a/src/util/path.js
+++ b/src/util/path.js
@@ -780,6 +780,36 @@
     path.push(['L', p1.x + multSignX * correction, p1.y + multSignY * correction]);
     return path;
   }
+  /**
+   * Transform a path by transforming each segment.
+   * it has to be a simplified path or it won't work.
+   * WARNING: this depends from pathOffset for correct operation
+   * @param {Array} path fabricJS parsed path commands
+   * @param {Array} transform matrix that represent the transformation
+   * @param {Object} [pathOffset] the fabric.Path pathOffset
+   * @param {Number} pathOffset.x
+   * @param {Number} pathOffset.y
+   * @returns {Array} the transformed path
+   */
+  function transformPath(path, transform, pathOffset) {
+    if (pathOffset) {
+      transform = fabric.util.multiplyTransformMatrices(
+        transform,
+        [1, 0, 0, 1, -pathOffset.x, -pathOffset.y]
+      );
+    }
+    return path.path.map(function(pathSegment) {
+      var newSegment = pathSegment.slice(0), point = {};
+      for (var i = 1; i < pathSegment.length - 1; i += 2) {
+        point.x = pathSegment[i];
+        point.y = pathSegment[i + 1];
+        point = fabric.util.transformPoint(point, transform);
+        newSegment[i] = point.x;
+        newSegment[i + 1] = point.y;
+      }
+      return newSegment;
+    });
+  }
 
   /**
    * Calculate bounding box of a elliptic-arc
@@ -829,15 +859,15 @@
   fabric.util.makePathSimpler = makePathSimpler;
   fabric.util.getSmoothPathFromPoints = getSmoothPathFromPoints;
   fabric.util.getPathSegmentsInfo = getPathSegmentsInfo;
-  fabric.util.fromArcToBeziers = fromArcToBeziers;
+  fabric.util.getBoundsOfCurve = getBoundsOfCurve;
+  fabric.util.getPointOnPath = getPointOnPath;
+  fabric.util.transformPath = transformPath;
   /**
    * Typo of `fromArcToBeziers` kept for not breaking the api once corrected.
    * Will be removed in fabric 5.0
    * @deprecated
    */
   fabric.util.fromArcToBeizers = fromArcToBeziers;
-  fabric.util.getBoundsOfCurve = getBoundsOfCurve;
-  fabric.util.getPointOnPath = getPointOnPath;
   // kept because we do not want to make breaking changes.
   // but useless and deprecated.
   fabric.util.getBoundsOfArc = getBoundsOfArc;

From 1c88a308d59fc3b0db026303ab55bb3a3dba5090 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 12:06:35 +0200
Subject: [PATCH 2/7] yes?

---
 src/util/path.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/util/path.js b/src/util/path.js
index cb90e263038..4694e6bbd9a 100644
--- a/src/util/path.js
+++ b/src/util/path.js
@@ -798,7 +798,7 @@
         [1, 0, 0, 1, -pathOffset.x, -pathOffset.y]
       );
     }
-    return path.path.map(function(pathSegment) {
+    return path.map(function(pathSegment) {
       var newSegment = pathSegment.slice(0), point = {};
       for (var i = 1; i < pathSegment.length - 1; i += 2) {
         point.x = pathSegment[i];

From 679b204792f8d65adf19aa02a2e5dfa5d231f0ca Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 22:54:41 +0200
Subject: [PATCH 3/7] ok

---
 src/brushes/pencil_brush.class.js |  2 +-
 src/shapes/path.class.js          | 13 ++++---------
 src/util/path.js                  | 13 ++++++++++++-
 test/unit/util.js                 |  9 +++++++++
 4 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/src/brushes/pencil_brush.class.js b/src/brushes/pencil_brush.class.js
index 68c7c7f052a..59fa9c058e4 100644
--- a/src/brushes/pencil_brush.class.js
+++ b/src/brushes/pencil_brush.class.js
@@ -192,7 +192,7 @@
      * @returns {boolean}
      */
     _isEmptySVGPath: function (pathData) {
-      var pathString = pathData.map(function (segment) { return segment.join(' '); }).join(' ');
+      var pathString = fabric.util.joinPath(pathData);
       return pathString === 'M 0 0 Q 0 0 0 0 L 0 0';
     },
 
diff --git a/src/shapes/path.class.js b/src/shapes/path.class.js
index ab379e5b3cf..24ea8bf63dc 100644
--- a/src/shapes/path.class.js
+++ b/src/shapes/path.class.js
@@ -56,12 +56,9 @@
 
       var fromArray = _toString.call(path) === '[object Array]';
 
-      this.path = fromArray
-        ? fabric.util.makePathSimpler(path)
-
-        : fabric.util.makePathSimpler(
-          fabric.util.parsePath(path)
-        );
+      this.path = fabric.util.makePathSimpler(
+        fromArray ? path : fabric.util.parsePath(path)
+      );
 
       if (!this.path) {
         return;
@@ -193,9 +190,7 @@
      * of the instance
      */
     _toSVG: function() {
-      var path = this.path.map(function(path) {
-        return path.join(' ');
-      }).join(' ');
+      var path = fabric.util.joinPath(this.path);
       return [
         '<path ', 'COMMON_PARTS',
         'd="', path,
diff --git a/src/util/path.js b/src/util/path.js
index 5dc0754aeba..433dd0c4ec2 100644
--- a/src/util/path.js
+++ b/src/util/path.js
@@ -784,7 +784,7 @@
    * Transform a path by transforming each segment.
    * it has to be a simplified path or it won't work.
    * WARNING: this depends from pathOffset for correct operation
-   * @param {Array} path fabricJS parsed path commands
+   * @param {Array} path fabricJS parsed and simplified path commands
    * @param {Array} transform matrix that represent the transformation
    * @param {Object} [pathOffset] the fabric.Path pathOffset
    * @param {Number} pathOffset.x
@@ -855,6 +855,17 @@
     });
   };
 
+  /**
+   * Join path commands to go back to svg format
+   * @deprecated
+   * @param {CanvasRenderingContext2D} ctx
+   * @param {Number} fx
+   * @param {Number} fy
+   * @param {Array} coords coords of the arc, without the front 'A/a'
+   */
+  fabric.util.joinPath = function(pathData) {
+    return pathData.map(function (segment) { return segment.join(' '); }).join(' ');
+  };
   fabric.util.parsePath = parsePath;
   fabric.util.makePathSimpler = makePathSimpler;
   fabric.util.getSmoothPathFromPoints = getSmoothPathFromPoints;
diff --git a/test/unit/util.js b/test/unit/util.js
index 8d1109812cd..16b2394b8a7 100644
--- a/test/unit/util.js
+++ b/test/unit/util.js
@@ -1090,4 +1090,13 @@
     assert.notOk(fabric.util.isTouchEvent({ type: 'mousedown' }));
     assert.notOk(fabric.util.isTouchEvent({ pointerType: 'mouse' }));
   });
+
+  QUnit.test('fabric.util.transformPath can scale a path', function(assert) {
+    assert.ok(typeof fabric.util.transformPath === 'function');
+    var path = new fabric.Path('M 100 100 L 200 100 L 170 200 z');
+    var oldPath = path.path;
+    var newPath = fabric.util.transformPath(path.path, [2, 0, 0, 2, 0, 0], path.pathOffset);
+    assert.equal(fabric.util.joinPath(oldPath), 'M 100 100 L 200 100 L 170 200 z');
+    assert.equal(fabric.util.joinPath(newPath), 'M -100 -100 L 100 -100 L 40 100 z');
+  });
 })();

From 62974eed39815ccefc40fff0f91c8904f0bd58bb Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 22:58:10 +0200
Subject: [PATCH 4/7] correct description

---
 src/util/path.js | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/util/path.js b/src/util/path.js
index 433dd0c4ec2..a187ea65387 100644
--- a/src/util/path.js
+++ b/src/util/path.js
@@ -857,11 +857,8 @@
 
   /**
    * Join path commands to go back to svg format
-   * @deprecated
-   * @param {CanvasRenderingContext2D} ctx
-   * @param {Number} fx
-   * @param {Number} fy
-   * @param {Array} coords coords of the arc, without the front 'A/a'
+   * @param {Array} pathData fabricJS parsed path commands
+   * @return {String} joined path 'M 0 0 L 20 30'
    */
   fabric.util.joinPath = function(pathData) {
     return pathData.map(function (segment) { return segment.join(' '); }).join(' ');

From ce5b9d85e1db6432f14b639de2a88b42d7f83121 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 23:01:31 +0200
Subject: [PATCH 5/7] correct description

---
 test/unit/util.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/test/unit/util.js b/test/unit/util.js
index 16b2394b8a7..5691acfcd53 100644
--- a/test/unit/util.js
+++ b/test/unit/util.js
@@ -1095,8 +1095,16 @@
     assert.ok(typeof fabric.util.transformPath === 'function');
     var path = new fabric.Path('M 100 100 L 200 100 L 170 200 z');
     var oldPath = path.path;
-    var newPath = fabric.util.transformPath(path.path, [2, 0, 0, 2, 0, 0], path.pathOffset);
+    var newPath = fabric.util.transformPath(path.path, [2, 0, 0, 2, 0, 0]);
     assert.equal(fabric.util.joinPath(oldPath), 'M 100 100 L 200 100 L 170 200 z');
-    assert.equal(fabric.util.joinPath(newPath), 'M -100 -100 L 100 -100 L 40 100 z');
+    assert.equal(fabric.util.joinPath(newPath), 'M 200 200 L 400 200 L 340 400 z');
+  });
+  QUnit.test('fabric.util.transformPath can apply a generic transform', function(assert) {
+    assert.ok(typeof fabric.util.transformPath === 'function');
+    var path = new fabric.Path('M 100 100 L 200 100 L 170 200 z');
+    var oldPath = path.path;
+    var newPath = fabric.util.transformPath(path.path, [1, 2, 3, 4, 5, 6], path.pathOffset);
+    assert.equal(fabric.util.joinPath(oldPath), 'M 100 100 L 200 100 L 170 200 z');
+    assert.equal(fabric.util.joinPath(newPath), 'M -195 -294 L -95 -94 L 175 246 z');
   });
 })();

From 9df002c801cf66dfeaaf1e921e967330ffb06816 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 23:01:49 +0200
Subject: [PATCH 6/7] correct description

---
 test/unit/util.js | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/test/unit/util.js b/test/unit/util.js
index 5691acfcd53..3d611a44a27 100644
--- a/test/unit/util.js
+++ b/test/unit/util.js
@@ -1091,7 +1091,7 @@
     assert.notOk(fabric.util.isTouchEvent({ pointerType: 'mouse' }));
   });
 
-  QUnit.test('fabric.util.transformPath can scale a path', function(assert) {
+  QUnit.test('fabric.util.transformPath can scale a path by 2', function(assert) {
     assert.ok(typeof fabric.util.transformPath === 'function');
     var path = new fabric.Path('M 100 100 L 200 100 L 170 200 z');
     var oldPath = path.path;
@@ -1100,7 +1100,6 @@
     assert.equal(fabric.util.joinPath(newPath), 'M 200 200 L 400 200 L 340 400 z');
   });
   QUnit.test('fabric.util.transformPath can apply a generic transform', function(assert) {
-    assert.ok(typeof fabric.util.transformPath === 'function');
     var path = new fabric.Path('M 100 100 L 200 100 L 170 200 z');
     var oldPath = path.path;
     var newPath = fabric.util.transformPath(path.path, [1, 2, 3, 4, 5, 6], path.pathOffset);

From 8ff3af22995fde99664a1d311a3333fe4515eb71 Mon Sep 17 00:00:00 2001
From: Andrea Bogazzi <andreabogazzi79@gmail.com>
Date: Fri, 27 Aug 2021 23:17:10 +0200
Subject: [PATCH 7/7] changelog

---
 CHANGELOG.md | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index af4872aa2a5..ee56f992336 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,7 +1,9 @@
 # Changelog
 
-## [next]
+## [4.6.0]
 
+- feat(fabric.util): added fabric.util.transformPath to add transformations to path points [#7300](https://github.com/fabricjs/fabric.js/pull/7300)
+- feat(fabric.util): added fabric.util.joinPath, the opposite of fabric.util.parsePath [#7300](https://github.com/fabricjs/fabric.js/pull/7300)
 - fix(fabric.util): use integers iterators [#7233](https://github.com/fabricjs/fabric.js/pull/7233)
 - feat(fabric.Text) add path rendering to text on path [#7328](https://github.com/fabricjs/fabric.js/pull/7328)
 - feat(fabric.iText): Add optional hiddenTextareaContainer to contain hiddenTextarea [#7314](https://github.com/fabricjs/fabric.js/pull/7314)