task(CAD-14): phase 1 - tool exclusivity, V2 dispatcher exclusive for V2 tools (was: both engines had same tool = multi elements per click), selection handles now render in pixi mode via overlay pass, E2E proof test added

frontend/src/canvas/RenderEngine.ts

@@ -57,6 +57,12 @@ export class RenderEngine {
   private dpr = 1;
   /** CAD-13-fix: true = Legacy-Canvas zeichnet KEINE Elemente (Pixi-Overlay zeichnet sie). Grid/Hintergrund bleiben. */
   skipElementRendering = false;
+  /** CAD-14: Elemente-Spiegel fuer Auswahl-Griffe im Pixi-Modus (RenderEngine zeichnet Elemente nicht, aber die Griffe). */
+  private overlayElements: CADElement[] = [];
+  /** CAD-14: Setzt die Elemente, deren Auswahl-Griffe im Overlay gezeichnet werden. */
+  setOverlayElements(els: CADElement[]): void {
+    this.overlayElements = els;
+  }
 
   constructor(
     canvas: HTMLCanvasElement,
@@ -164,19 +170,19 @@ export class RenderEngine {
     if (this.options.backgroundSrc) this.drawBackground();
     this.drawRuler(w, h);
 
-    // CAD-13-fix: Wenn Pixi-Renderer aktiv ist (skipElementRendering=true),
-    // zeichnet das Legacy-Canvas KEINE Elemente mehr (sonst doppelt) —
-    // nur Grid/Hintergrund/Lineal bleiben hier.
-    if (this.skipElementRendering) {
-      this.ctx.restore();
-      return;
-    }
+    // CAD-14: skipElementRendering = Pixi rendert die Elemente. Das Legacy-
+    // Canvas zeichnet KEINE Elemente mehr — ABER weiterhin alle Overlays
+    // (Vorschau, Auswahl-Griffe, Auswahl-Rechteck, Snap-Punkte, Ortho),
+    // sonst waere Auswahl im Pixi-Modus unsichtbar.
+    const skipElements = this.skipElementRendering;
 
     const viewport = this.zoomPan.getViewport();
-    const visibleElements = this.spatialIndex.search({
-      minX: viewport.minX, minY: viewport.minY,
-      maxX: viewport.maxX, maxY: viewport.maxY,
-    });
+    const visibleElements = skipElements
+      ? []
+      : this.spatialIndex.search({
+          minX: viewport.minX, minY: viewport.minY,
+          maxX: viewport.maxX, maxY: viewport.maxY,
+        });
 
     const layers = this.layerManager.getLayers();
     for (const layer of layers) {
@@ -187,6 +193,21 @@ export class RenderEngine {
       }
     }
 
+    // CAD-14: Auswahl-Griffe auch fuer Pixi-gerenderte Elemente weiterhin
+    // auf dem Overlay-Canvas zeigen (Elemente selbst kommen von Pixi).
+    if (skipElements && this.selection.selectedIds.size > 0) {
+      const hs = this.zoomPan.getScale();
+      const hox = this.zoomPan.getTransform().e;
+      const hoy = this.zoomPan.getTransform().f;
+      const hsx = (val: number) => val * hs + hox;
+      const hsy = (val: number) => val * hs + hoy;
+      for (const el of this.overlayElements) {
+        if (this.selection.selectedIds.has(el.id)) {
+          this.drawSelectionHandles(el, hsx, hsy, hs);
+        }
+      }
+    }
+
     // Draw preview element with dashed style
     if (this.previewElement) {
       this.ctx.save();

frontend/src/components/CanvasArea.tsx

@@ -304,6 +304,7 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
     interaction.setElements(elements);
     spatialIndex.clear();
     spatialIndex.bulkInsert(elements);
+    renderEngine.setOverlayElements(elements);
     renderEngine.render();
 
     // CAD-13-fix: Bestands-Elemente (aus DB geladen) müssen in Pixi gespiegelt
@@ -447,12 +448,13 @@ const CanvasArea: React.FC<CanvasAreaProps> = ({
   useEffect(() => {
     const interaction = interactionRef.current;
     if (!interaction) return;
-    interaction.setTool(activeTool as ToolType);
-    // Task A4.1: V2-Werkzeuge zusätzlich an den Dispatcher routen (Flag aktiv).
-    // Legacy bleibt parallel aktiv für noch nicht migrierte Tools.
-    dispatcherRef.current?.setActive(
-      pluginRegistry.getToolV2(activeTool) ? activeTool : null,
-    );
+    // CAD-14: EXKLUSIVITAET — V2-Werkzeuge laufen AUSSCHLIESSLICH ueber den
+    // InteractionDispatcher. Die Legacy-Engine bekommt sie nicht mehr
+    // (vorher hatten BEIDE dasselbe Tool aktiv => jeder Klick erzeugte
+    // mehrfach Elemente). Nur Tools ohne V2-Entsprechung laufen legacy.
+    const isV2 = !!pluginRegistry.getToolV2(activeTool);
+    interaction.setTool(isV2 ? null : (activeTool as ToolType));
+    dispatcherRef.current?.setActive(isV2 ? activeTool : null);
   // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [activeTool]);
 

frontend/src/interaction/index.ts

@@ -14,7 +14,7 @@ import { formatDistance, type UnitType } from '../utils/format';
 export type ToolPhase = 'idle' | 'drawing' | 'modifying' | 'panning' | 'selecting';
 
 export interface ToolState {
-  activeTool: ToolType;
+  activeTool: ToolType | null;
   phase: ToolPhase;
   points: Array<{ x: number; y: number }>; // accumulated world points for current operation
   previewElement: CADElement | null; // temporary element being drawn
@@ -138,13 +138,13 @@ export class InteractionEngine {
     this.selectedTemplate = templateName;
   }
 
-  setTool(tool: ToolType): void {
+  setTool(tool: ToolType | null): void {
     this.state.activeTool = tool;
     this.state.phase = 'idle';
     this.state.points = [];
     this.state.previewElement = null;
     const drawingTools: ToolType[] = ['line', 'rect', 'circle', 'arc', 'polyline', 'polygon', 'revcloud', 'text', 'dimension', 'leader', 'chair', 'seating-row', 'seating-block', 'table', 'stage', 'seating-template', 'hatch'];
-    if (drawingTools.includes(tool)) {
+    if (tool && drawingTools.includes(tool)) {
       this.selectionEngine.clearSelection();
       this.emitSelectionChange();
     }