# REGEN Command [GstarCAD 2020](Help%20System/GSTARCAD/2020/Index.md) → [Commands](Help%20System/GSTARCAD/2020/Commands/(Commands).md) → [R](Help%20System/GSTARCAD/2020/Commands/R/(R).md) The REGEN command is used to regenerate the whole drawing from the current viewport. ## Command Access: > **Menu:** View \> Gegen **Command:** REGEN ## Command Prompts: > Regenerating model. ## Function Description: This command could regenerate the whole drawing from current viewport and recalculate all screen coordinates of objects. As well it could regenerate graph database index to optimize display and object selection performance. ## Other versions with matching text [GstarCAD 2016](../../../2016/Commands/R/REGEN%20Command.md) · [GstarCAD 2017](../../../2017/Commands/R/REGEN%20Command.md) · [GstarCAD 2018](Help%20System/GSTARCAD/2018/Commands/R/REGEN%20Command.md) · [GstarCAD 2019](Help%20System/GSTARCAD/2019/Commands/R/REGEN%20Command.md) · [GstarCAD 2021](Help%20System/GSTARCAD/2021/Commands/R/REGEN%20Command.md)