# SURFACEAUTOTRIM System Variable [GstarCAD 2027](Help%20System/GSTARCAD/2027/Index.md) → [System Variables](Help%20System/GSTARCAD/2027/System%20Variables/(System%20Variables).md) → [S](Help%20System/GSTARCAD/2027/System%20Variables/S/(S).md) ## Function Description: The SURFACEAUTOTRIM system variable is used to set whether to auto trim surface when geometry projecting to surface. | | | | --- | --- | | Type | Integer | | Saved in | Registry | | Initial value | 0 | | Range | 0,1 | ## System Variable Value: **0:** do not trim surface when geometry projecting to surface. **1:** auto trim surface when geometry projecting to surface --- [Original help](https://www.gstarcad.net/help/GstarCAD_2027_en-US/detail/systemVariables_Sgsv/SURFACEAUTOTRIM.html) · © Gstarsoft Co., Ltd.