From 8db23005388a1cefa66698b7de8689876ccf55ac Mon Sep 17 00:00:00 2001
From: Googler <noreply@google.com>
Date: Tue, 23 Jun 2026 12:58:48 -0700
Subject: [PATCH] Halve the zoom speed and step in Trajectory Viewer v2.

- Zoom in/out speeds for mouse scroll wheels and trackpads in the v2 Angular-based Trajectory Viewer were too fast for comfortable navigation.
- Extends the `ZoomConfig` in `workflow_graph` to optionally accept `scrollStepPerDelta` for trackpad scroll customization.
- Halves the default zoom step from `0.05` to `0.025` and the trackpad scroll delta scale from `0.02` to `0.01` within the Trajectory Viewer configuration.
- Wires up the new config to `<ai-dag-renderer>` in Trajectory Viewer v2's DAG component template.

PiperOrigin-RevId: 936840540
---
 src/app/data_types_internal.ts     | 10 +++++++---
 src/app/zooming_layer.directive.ts |  6 +++---
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/app/data_types_internal.ts b/src/app/data_types_internal.ts
index 18db32d..33fb235 100644
--- a/src/app/data_types_internal.ts
+++ b/src/app/data_types_internal.ts
@@ -390,17 +390,21 @@ export interface ZoomConfig {
   max: number;
   /** Buttons should increment or decrement by what magnitude. Default: .05 */
   step: number;
+  /** Increment or decrement per scroll / trackpad delta. Default: .02 */
+  scrollStepPerDelta?: number;
 }
+
+/** Increment or decrement per scroll / trackpad delta. */
+export const SCROLL_STEP_PER_DELTA = .02;
+
 /** Default zoom config that can be used for DAG Toolbar or DAG Renderer */
 export const defaultZoomConfig: ZoomConfig = {
   max: 1.5,
   min: .2,
   step: .10,
+  scrollStepPerDelta: SCROLL_STEP_PER_DELTA,
 };
 
-/** Increment or decrement per scroll / trackpad delta. */
-export const SCROLL_STEP_PER_DELTA = .02;
-
 /**
  * Allows you to construct a full DAG Zoom Config set from partial entries
  * which override the defaults
diff --git a/src/app/zooming_layer.directive.ts b/src/app/zooming_layer.directive.ts
index dba6eed..cfcbebf 100644
--- a/src/app/zooming_layer.directive.ts
+++ b/src/app/zooming_layer.directive.ts
@@ -144,13 +144,13 @@ export class ZoomingLayer implements OnInit, OnDestroy {
   }
 
   private zoomOnWheel($e: WheelEvent) {
-    const {min, max} = this.zoomStepConfig;
+    const {min, max, step, scrollStepPerDelta = SCROLL_STEP_PER_DELTA} = this.zoomStepConfig;
     const invSign = $e.deltaY > 0 ? -1 : 1;
     let newZoom = this.stateService.zoom.value +
         invSign *
             Math.min(
-                SCROLL_STEP_PER_DELTA * Math.abs($e.deltaY),
-                this.zoomStepConfig.step);
+                scrollStepPerDelta * Math.abs($e.deltaY),
+                step);
     newZoom = clampVal(newZoom, min, max);
 
     const container = this.dagWrapper.nativeElement.getBoundingClientRect();