From 251b33390544419a128a4a35a5b000210a250ee0 Mon Sep 17 00:00:00 2001
From: Adrian Solberg <adrianhsolberg@gmail.com>
Date: Thu, 25 Sep 2025 19:31:03 +0200
Subject: [PATCH] feat(#9): limit zoom out

---
 src/potreeViewer.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/src/potreeViewer.js b/src/potreeViewer.js
index 2e7272e..f27edc7 100644
--- a/src/potreeViewer.js
+++ b/src/potreeViewer.js
@@ -3,6 +3,11 @@ export async function createPotreeViewer(containerId, pointcloudUrl, settings) {
     useDefaultRenderLoop: false
   })
 
+  // Remove original scroll listener and add new one
+  const oc = viewer.orbitControls;
+  oc.removeEventListener('mousewheel', oc._listeners?.mousewheel?.[0]);
+  oc.addEventListener('mousewheel', clampScrollRadius);
+
   if (settings.edl) viewer.setEDLEnabled(true)
   if (settings.fov) viewer.setFOV(settings.fov)
   if (settings.pointBudget) viewer.setPointBudget(settings.pointBudget)
@@ -43,3 +48,14 @@ export async function createPotreeViewer(containerId, pointcloudUrl, settings) {
 
   return viewer
 }
+
+function clampScrollRadius(e) {
+  let resolvedRadius = this.scene.view.radius + this.radiusDelta;
+  let newRadius = resolvedRadius - e.delta * resolvedRadius * 0.1;
+
+  const maxRadius = 10000000;
+  if (newRadius > maxRadius) newRadius = maxRadius;
+
+  this.radiusDelta = newRadius - this.scene.view.radius;
+  this.stopTweens();
+}