The physics glitch or physics bug is a rare glitch that causes physics in a server to act very strange and completely out of balance. Usually it results in physical props floating in mid-air and having little to no gravity at all or they will simply move and interact incorrectly with solidity in the map(s). The reason of this glitch is yet unknown.
Currently the only map that triggers/causes this issue is ze_LOTR_Minas_Tirith. The map is widely known for being able to crash the server's physics after a considerable amount of time. When this happens, the map is completely unplayable, as it uses a vast amount of physical props that play a big part in the gameplay of this map.
The following theories have been stated that may be the cause of the glitch:
- The map has simply too many prop_physics that the servers need to keep tracking, and as such crash the physics system in Source.
- The props in Minas Tirith can be placed inside solids such as walls and the floor, and as such may be a possible reason that the physics get crashed since physics are not supposed to get past solids in the first place.
- Some people believe that it depends on the amount of time the server runs the map (not Minas Tirith in particular), and since Minas Tirith requires almost all extends to win all of the 8 stages (2x4 stages) it takes so long for the server to calculate the physics that the server can't possibly keep the calculations up. This theory is heavily unsupported as Source doesn't calculate constantly all physics within a map in real-time. Once a physics entity has a fixed position, it will be frozen on that spot until a player interacts with it again so that the server doesn't need to make unnecessary calculations.
Regardless of the above theories, this glitch has led Minas Tirith to be removed from the rotation lists on many servers, and as such is now harder to find. Servers make exceptions as to only allow admins vote Minas Tirith as a possible nomination, or simply as the nextmap so that they can play Minas Tirith only a couple of times in the week instead of never. This is mainly because once the physics crash, the server needs to be restarted completely with potentially the cost and loss of players on the server as a result.
Numerous fixes have been suggested, yet none of them have ever been executed nor tested.
- Generally players believe that removing the physical items and replacing them with a prop_dynamic is the best solution, as this does not involve calculations. Surely, movement within the object and against other objects (except players) will not happen anymore, and objects could be placed inside each other the whole time without the engine doing anything about it, but it would easily solve the problem, and with some careful teamwork, you can build strong barricades with this method as well.
- It as also believed that a specific flag option within the physical props causes the crash, and unflagging it would solve the problem in its entirity.
- Some suggested removing physical props and replacing them with brush-based physicals, but is highly unsupported as it still involves the same physical calculations.
Aside from this, much help from other mappers and offers to fix the map by them has sufaced ever since. Hannibal has yet to answer on either fixing it himself (again as he already tried to fix it many times) or allowing someone else to do it