From c6a48aecc85628fa6ca32fbe559476f661699ec4 Mon Sep 17 00:00:00 2001
From: Sean Kim <SeanCTKim@protonmail.com>
Date: Sun, 14 Sep 2025 11:08:25 +0200
Subject: [PATCH] Fix #146233: Dyntopo sample detail size crashes with cursor
 not on mesh

Introduced by 45d9bfa734aae456ca83953e56953fae94617151

Pull Request: https://projects.blender.org/blender/blender/pulls/146249
---
 source/blender/editors/sculpt_paint/sculpt_detail.cc | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/source/blender/editors/sculpt_paint/sculpt_detail.cc b/source/blender/editors/sculpt_paint/sculpt_detail.cc
index 652fc7612bb..12b739ec1a2 100644
--- a/source/blender/editors/sculpt_paint/sculpt_detail.cc
+++ b/source/blender/editors/sculpt_paint/sculpt_detail.cc
@@ -637,7 +637,11 @@ static void dyntopo_detail_size_sample_from_surface(Object &ob,
                                                     DyntopoDetailSizeEditCustomData *cd)
 {
   SculptSession &ss = *ob.sculpt;
-  BMVert *active_vertex = std::get<BMVert *>(ss.active_vert());
+  const ActiveVert active_vert = ss.active_vert();
+  if (std::holds_alternative<std::monostate>(active_vert)) {
+    return;
+  }
+  BMVert *active_vertex = std::get<BMVert *>(active_vert);
 
   float len_accum = 0;
   BMeshNeighborVerts neighbors;