I also see a permanent display of such a tree in the main window as a waste of sceenspace,
BUT: entity names may be hard to remember exactly.
Thus, a search window, usually hidden and only displayed / overlaying the main windon on response to a key press or a Search Button, would be an ideal solution. This window would
* display the dreaded entity tree with all the information you mentioned (scrollable, of course),
* have the textfield to enter the search string for entity names in the menu line or the bottom line.
* Single left click on the respecitve entity of the tree should position the camera of the main window so that the visible area is centered around the respective entity,
*Double left click on an entity in the tree should do likewise AND end (=hide) the search window, returning us to the main window.
The search window could be fitted with a few more buttons or a menu, e.g. for
* positioning the main window back to where the position was when the search window was called
* positioning the main window back to the last position before the current position (plus a small radius around it to account for involuntary small mouse movements). This feature would come in very handy if one has to fine-tune views from and to a certain point ( e.g., from an elevated point for a sniper to his target area)
* if the database allowed for a "special name" attached to an object, it might be much easier to identify it and go to it (e.g., of the 386 trees distributed over the landscape, only one may be the "HangingTree" and only one other the "DruidTree").
Maybe, this feature could even double as a very fast way to move between imprtant points on large maps, especially, if a filter could be set to display only nodes with special entity names.
On the more technical side, we can have statistical information ("so and so many instances of entity 'xyz') - and even thumbnails of the entity displayed while the mouse cursor is hovering over the respective node in the tree, just to be sure)
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