Making Arrow filtering and Center Alignment toggles persistent across CSE updates

src/commons/sideContent/content/SideContentCseMachine.tsx

@@ -210,14 +210,19 @@
       this.handleResize();
     }
     if (prevProps.needCseUpdate && !this.props.needCseUpdate) {
-      CseMachine.resetArrowOriginFilters();
+      const preservedStep = Math.max(this.state.value, 0);
       this.setState({ arrowFilterOpen: false });
-      this.stepFirst();
+
       if (this.isJava()) {
         JavaCseMachine.clearCse();
       } else {
         CseMachine.clearCse();
       }
+
+      // Re-run the stepper at the preserved step so the display remains at the
+      // same step after editor update while still refreshing the CSE internals.
+      this.sliderShift(preservedStep);
+      this.sliderRelease(preservedStep);
     }
   }
 
@@ -706,7 +711,7 @@
     dispatch,
   );
 
 export const SideContentCseMachine = connect(
   mapStateToProps,
   mapDispatchToProps,
 )(SideContentCseMachineBase);

src/features/cseMachine/CseMachine.tsx

@@ -465,7 +465,6 @@ export default class CseMachine {
   }
 
   static clearCse() {
-    CseMachine.resetArrowOriginFilters();
     if (this.setVis) {
       this.setVis(undefined);
       CseMachine.environmentTree = undefined;

src/features/cseMachine/CseMachineLayout.tsx

@@ -922,6 +922,12 @@ export class Layout {
           const currentWidth = frame.width();
           frame.reassignWidth(Math.max(currentWidth, fixedWidth));
         }
+
+        // get predetermined y coordinate
+        if (cache.framesY.has(id)) {
+          const fixedY = Layout.getGhostFrameY(id)!;
+          frame.reassignCoordinatesY(fixedY);
+        }
       });
     });
   }

src/pages/playground/Playground.tsx

@@ -424,7 +424,12 @@ const Playground: React.FC<PlaygroundProps> = props => {
   const autorunButtonHandlers = useMemo(() => {
     return {
       handleEditorEval: () => {
+        const wasCenterAligned = CseMachine.getCenterAlignment();
         CseMachine.clearCachedLayouts();
+        if (wasCenterAligned) {
+          CseMachine.toggleCenterAlignment();
+        }
+
         // reset stepper before evaluation
         dispatch(WorkspaceActions.updateCurrentStep(-1, workspaceLocation));
         dispatch(WorkspaceActions.updateStepsTotal(0, workspaceLocation));
@@ -438,7 +443,7 @@ const Playground: React.FC<PlaygroundProps> = props => {
 
         dispatch(WorkspaceActions.evalEditor(workspaceLocation));
         CseMachine.setClearDeadFrames(false);
-        if (CseMachine.getCenterAlignment()) {
+        if (wasCenterAligned) {
           CseMachine.toggleCenterAlignment();
         }
       },