From 830288384325bfdd4188f6d645a3346c368aaa19 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Thu, 24 Feb 2022 12:54:11 +0100
Subject: [PATCH] Sketcher: fix crash in function 'Convert to B-Spline' See
 also the forum thread:
 https://forum.freecadweb.org/viewtopic.php?f=19&t=66470

---
 src/Mod/Sketcher/Gui/EditModeGeometryCoinManager.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Mod/Sketcher/Gui/EditModeGeometryCoinManager.cpp b/src/Mod/Sketcher/Gui/EditModeGeometryCoinManager.cpp
index 84a1df7544..6c145101b0 100644
--- a/src/Mod/Sketcher/Gui/EditModeGeometryCoinManager.cpp
+++ b/src/Mod/Sketcher/Gui/EditModeGeometryCoinManager.cpp
@@ -310,7 +310,7 @@ void EditModeGeometryCoinManager::updateGeometryColor(const GeoListFacade & geol
         ViewProviderSketchCoinAttorney::executeOnSelectionPointSet(viewProvider,
             [pcolor, PtNum, preselectpointmfid, layerId = l, &coinMapping = coinMapping, drawingParameters = this->drawingParameters](const int i) {
                 auto pointindex = coinMapping.getIndexLayer(i);
-                if (layerId == pointindex.layerId && pointindex.fieldIndex < PtNum) {
+                if (layerId == pointindex.layerId && pointindex.fieldIndex >= 0 && pointindex.fieldIndex < PtNum) {
                     pcolor[pointindex.fieldIndex] = (preselectpointmfid == pointindex)
                         ? drawingParameters.PreselectSelectedColor : drawingParameters.SelectColor;
                 }