By default each tab is set to completely regenerate each time a switch is made to make a tab current. Here is a tip to help speed up regeneration when switching between tabs:ġ) The LAYOUTREGENCTL command can improve performance by controlling how the display list is updated in the Model and Layout tabs. One major slow-down in performance can be regeneration time when switching between Layout and Model tabs. Any increase in performance of handling and displaying this data is a welcome sight. Civil 3D drawings can often times become quite large and data intensive.