fix: Elbow arrow fixedpoint flipping now properly flips on inverted resize and flip action (#8324)

* Flipping action now properly mirrors selections with elbow arrows
* Flipping action now re-centers the selection to the original center to avoid "walking" selections on repeated flipping

packages/excalidraw/element/binding.ts

@@ -39,6 +39,7 @@ import {
   isBindingElement,
   isBoundToContainer,
   isElbowArrow,
+  isFixedPointBinding,
   isFrameLikeElement,
   isLinearElement,
   isRectangularElement,
@@ -797,7 +798,7 @@ export const bindPointToSnapToElementOutline = (
           isVertical
             ? Math.abs(p[1] - i[1]) < 0.1
             : Math.abs(p[0] - i[0]) < 0.1,
-        )[0] ?? point;
+        )[0] ?? p;
   }
 
   return p;
@@ -1013,7 +1014,7 @@ const updateBoundPoint = (
   const direction = startOrEnd === "startBinding" ? -1 : 1;
   const edgePointIndex = direction === -1 ? 0 : linearElement.points.length - 1;
 
-  if (isElbowArrow(linearElement)) {
+  if (isElbowArrow(linearElement) && isFixedPointBinding(binding)) {
     const fixedPoint =
       normalizeFixedPoint(binding.fixedPoint) ??
       calculateFixedPointForElbowArrowBinding(

packages/excalidraw/element/dragElements.ts

@@ -35,7 +35,6 @@ export const dragSelectedElements = (
 ) => {
   if (
     _selectedElements.length === 1 &&
-    isArrowElement(_selectedElements[0]) &&
     isElbowArrow(_selectedElements[0]) &&
     (_selectedElements[0].startBinding || _selectedElements[0].endBinding)
   ) {
@@ -43,13 +42,7 @@ export const dragSelectedElements = (
   }
 
   const selectedElements = _selectedElements.filter(
-    (el) =>
-      !(
-        isArrowElement(el) &&
-        isElbowArrow(el) &&
-        el.startBinding &&
-        el.endBinding
-      ),
+    (el) => !(isElbowArrow(el) && el.startBinding && el.endBinding),
   );
 
   // we do not want a frame and its elements to be selected at the same time

packages/excalidraw/element/linearElementEditor.ts

@@ -102,6 +102,7 @@ export class LinearElementEditor {
   public readonly endBindingElement: ExcalidrawBindableElement | null | "keep";
   public readonly hoverPointIndex: number;
   public readonly segmentMidPointHoveredCoords: GlobalPoint | null;
+  public readonly elbowed: boolean;
 
   constructor(element: NonDeleted<ExcalidrawLinearElement>) {
     this.elementId = element.id as string & {
@@ -131,6 +132,7 @@ export class LinearElementEditor {
     };
     this.hoverPointIndex = -1;
     this.segmentMidPointHoveredCoords = null;
+    this.elbowed = isElbowArrow(element) && element.elbowed;
   }
 
   // ---------------------------------------------------------------------------
@@ -1477,7 +1479,9 @@ export class LinearElementEditor {
         nextPoints,
         vector(offsetX, offsetY),
         bindings,
-        options,
+        {
+          isDragging: options?.isDragging,
+        },
       );
     } else {
       const nextCoords = getElementPointsCoords(element, nextPoints);

packages/excalidraw/element/resizeElements.ts

@@ -9,6 +9,7 @@ import type {
   ExcalidrawTextElementWithContainer,
   ExcalidrawImageElement,
   ElementsMap,
+  ExcalidrawArrowElement,
   NonDeletedSceneElementsMap,
   SceneElementsMap,
 } from "./types";
@@ -909,6 +910,8 @@ export const resizeMultipleElements = (
       fontSize?: ExcalidrawTextElement["fontSize"];
       scale?: ExcalidrawImageElement["scale"];
       boundTextFontSize?: ExcalidrawTextElement["fontSize"];
+      startBinding?: ExcalidrawArrowElement["startBinding"];
+      endBinding?: ExcalidrawArrowElement["endBinding"];
     };
   }[] = [];
 
@@ -993,19 +996,6 @@ export const resizeMultipleElements = (
 
     mutateElement(element, update, false);
 
-    if (isArrowElement(element) && isElbowArrow(element)) {
-      mutateElbowArrow(
-        element,
-        elementsMap,
-        element.points,
-        undefined,
-        undefined,
-        {
-          informMutation: false,
-        },
-      );
-    }
-
     updateBoundElements(element, elementsMap, {
       simultaneouslyUpdated: elementsToUpdate,
       oldSize: { width: oldWidth, height: oldHeight },
@@ -1059,7 +1049,7 @@ const rotateMultipleElements = (
         (centerAngle + origAngle - element.angle) as Radians,
       );
 
-      if (isArrowElement(element) && isElbowArrow(element)) {
+      if (isElbowArrow(element)) {
         const points = getArrowLocalFixedPoints(element, elementsMap);
         mutateElbowArrow(element, elementsMap, points);
       } else {

packages/excalidraw/element/routing.ts

@@ -41,7 +41,6 @@ import { mutateElement } from "./mutateElement";
 import { isBindableElement, isRectanguloidElement } from "./typeChecks";
 import type {
   ExcalidrawElbowArrowElement,
-  FixedPointBinding,
   NonDeletedSceneElementsMap,
   SceneElementsMap,
 } from "./types";
@@ -73,13 +72,12 @@ export const mutateElbowArrow = (
   elementsMap: NonDeletedSceneElementsMap | SceneElementsMap,
   nextPoints: readonly LocalPoint[],
   offset?: Vector,
-  otherUpdates?: {
-    startBinding?: FixedPointBinding | null;
-    endBinding?: FixedPointBinding | null;
-  },
+  otherUpdates?: Omit<
+    ElementUpdate<ExcalidrawElbowArrowElement>,
+    "angle" | "x" | "y" | "width" | "height" | "elbowed" | "points"
+  >,
   options?: {
     isDragging?: boolean;
-    disableBinding?: boolean;
     informMutation?: boolean;
   },
 ) => {

packages/excalidraw/element/typeChecks.ts

@@ -320,9 +320,12 @@ export const getDefaultRoundnessTypeForElement = (
 };
 
 export const isFixedPointBinding = (
-  binding: PointBinding,
+  binding: PointBinding | FixedPointBinding,
 ): binding is FixedPointBinding => {
-  return binding.fixedPoint != null;
+  return (
+    Object.hasOwn(binding, "fixedPoint") &&
+    (binding as FixedPointBinding).fixedPoint != null
+  );
 };
 
 // TODO: Move this to @excalidraw/math

packages/excalidraw/element/types.ts

@@ -193,6 +193,7 @@ export type ExcalidrawElement =
   | ExcalidrawGenericElement
   | ExcalidrawTextElement
   | ExcalidrawLinearElement
+  | ExcalidrawArrowElement
   | ExcalidrawFreeDrawElement
   | ExcalidrawImageElement
   | ExcalidrawFrameElement
@@ -268,15 +269,19 @@ export type PointBinding = {
   elementId: ExcalidrawBindableElement["id"];
   focus: number;
   gap: number;
-  // Represents the fixed point binding information in form of a vertical and
-  // horizontal ratio (i.e. a percentage value in the 0.0-1.0 range). This ratio
-  // gives the user selected fixed point by multiplying the bound element width
-  // with fixedPoint[0] and the bound element height with fixedPoint[1] to get the
-  // bound element-local point coordinate.
-  fixedPoint: FixedPoint | null;
 };
 
-export type FixedPointBinding = Merge<PointBinding, { fixedPoint: FixedPoint }>;
+export type FixedPointBinding = Merge<
+  PointBinding,
+  {
+    // Represents the fixed point binding information in form of a vertical and
+    // horizontal ratio (i.e. a percentage value in the 0.0-1.0 range). This ratio
+    // gives the user selected fixed point by multiplying the bound element width
+    // with fixedPoint[0] and the bound element height with fixedPoint[1] to get the
+    // bound element-local point coordinate.
+    fixedPoint: FixedPoint;
+  }
+>;
 
 export type Arrowhead =
   | "arrow"