respect initial type when switching between linears

packages/element/src/newElement.ts

@@ -44,7 +44,6 @@ import type {
   ExcalidrawIframeElement,
   ElementsMap,
   ExcalidrawArrowElement,
-  FixedSegment,
   ExcalidrawElbowArrowElement,
 } from "./types";
 
@@ -478,7 +477,7 @@ export const newArrowElement = <T extends boolean>(
     endArrowhead?: Arrowhead | null;
     points?: ExcalidrawArrowElement["points"];
     elbowed?: T;
-    fixedSegments?: FixedSegment[] | null;
+    fixedSegments?: ExcalidrawElbowArrowElement["fixedSegments"] | null;
   } & ElementConstructorOpts,
 ): T extends true
   ? NonDeleted<ExcalidrawElbowArrowElement>

packages/excalidraw/components/ShapeSwitch.tsx

@@ -508,9 +508,48 @@ export const switchShapes = (
     if (nextType && isConvertibleLinearType(nextType)) {
       const convertedElements: Record<string, ExcalidrawElement> = {};
       for (const element of selectedLinearSwitchableElements) {
+        const { properties, initialType } =
+          editorJotaiStore.get(shapeSwitchLinearAtom)?.[element.id] || {};
+
+        // If the initial type is not elbow, and when we switch to elbow,
+        // the linear line might be "bent" and the points would likely be different.
+        // When we then switch to other non elbow types from this converted elbow,
+        // we still want to use the original points instead.
+        if (
+          initialType &&
+          properties &&
+          isElbowArrow(element) &&
+          initialType !== "elbowArrow" &&
+          nextType !== "elbowArrow"
+        ) {
+          // first convert back to the original type
+          const originalType = convertElementType(
+            element,
+            initialType,
+            app,
+          ) as ExcalidrawLinearElement;
+          // then convert to the target type
+          const converted = convertElementType(
+            initialType === "line"
+              ? newLinearElement({
+                  ...originalType,
+                  ...properties,
+                  type: "line",
+                })
+              : newArrowElement({
+                  ...originalType,
+                  ...properties,
+                  type: "arrow",
+                }),
+            nextType,
+            app,
+          );
+          convertedElements[converted.id] = converted;
+        } else {
           const converted = convertElementType(element, nextType, app);
           convertedElements[converted.id] = converted;
         }
+      }
 
       const nextElements = [];