DarkRadiant experiences huge slowdowns on complex maps when moving the camera or toggling filters

[MirceaKitsune]

DarkRadiant is presently suffering from huge slowdowns when editing complex maps. They appear to increase the more models and entities are added to a map: With the building modules used in a lot of places, one of my maps is at the point where DR freezes for over one second whenever I merely toggle a filter which is very annoying for every repeated action. The lag occurs both when moving the 2D or 3D camera or viewport around, as well as enabling or disabling filters or using Control + F to go in and out of editing a group.

From what I can tell as an end user, this seems to occur because DR drops models that are no longer being rendered from memory, so whenever a change in the camera or viewport is made everything that pops into view or is recalculated floods back in. While this may be nice to save on RAM, my suggestion would be a change or at least an option to disable this behavior and keep everything precached: Like TDM itself, DR should maintain every model and texture used by the map in memory, only removing it once every last instance has been changed or deleted from the map being edited.