fix crash in 3d when one push shift and intercat
fix crash in 3d when one push shift and intercat

rdebroiz/medInria-public,aabadie/medInria-public,aabadie/medInria-public,NicolasSchnitzler/medInria-public,NicolasSchnitzler/medInria-public,aabadie/medInria-public,NicolasSchnitzler/medInria-public,rdebroiz/medInria-public,rdebroiz/medInria-public