"Siege" maps versus NS2 game mechanics
bp2008
Join Date: 2012-11-28 Member: 173581Members, Reinforced - Shadow, WC 2013 - Gold
Join Date: 2012-11-28 Member: 173581Members, Reinforced - Shadow, WC 2013 - Gold
I have put together two "siege" maps for NS2 so far (similar to those found in NS1). However NS2 has mechanics which make this type of map difficult.
The core of a siege map is the fact that certain areas of the map are inaccessible for a period of time. Typically this is done via doors which are locked until a set time passes (func_door in ExtraEntitesMod), but also can be done with teleporters (also ExtraEntitesMod) that are not enabled until a certain time. There is also a siege room directly adjacent to the hives from which marines can end the game if they survive long enough for the room to become accessible.
Each of these siege mechanics has problems in the NS2 game engine, primarily stemming from NS2's use of a navigation mesh and infestation / cysting mechanics.
--- Doors ---
Thus far, the only easy option for timed doors is to use func_door and logic_timer from ExtraEntitesMod. The door is perfect for stopping players, but for commanders, the doors may as well not exist. Aliens can cyst right past them, and drifters, MACs, and ARCs can roll through a locked door almost as if it wasn't even there. Investigation with the nav_debug command reveals that the locked doors only partially and somewhat inconsistently block NS2's navigation mesh, which explains why AI units can pass unhindered. Some doors block the nav mesh when locked, but not when unlocked. This prevents AI units from passing a locked door but allows them passage when the door is unlocked.
--- Teleporters ---
Teleporters are great for maps with an unconventional structure, and you might think they would be the solution for ARCs entering the siege room early, but they aren't. NS2 requires the navigation mesh to reach and fill each room where you intend to build or send AI units, so each room also needs an unbroken ground-based path! That means AI units can get in!
--- Getting into the siege room early ---
Infestation grows in a circular area around hives and cysts. It does not apparently care about walls and will gladly spread from the hive room directly into the adjacent siege room! The only way I have found to stop aliens from building on this infestation in the siege room is to make the susceptible areas non-buildable in the map editor. Unfortunately, you can't order an ARC onto an unbuildable area! So you need at least one buildable area in the siege room near enough the hives that you can send ARCs there to deploy them yet small enough and close enough to a wall that aliens can't build on it.
Further, cyst chaining ignores line of sight if there is not a reasonably short unbroken path between the new cyst and the nearest already-connected cyst. In many cases, this means you can't put a siege room within cysting range of any other buildable location.
--- How to avoid these issues ---
If you build a siege map, build the basic layout EARLY and test thoroughly to ensure aliens can't build in the siege room and that all the doors block AI units when they should. You may find that significant changes are needed!
The core of a siege map is the fact that certain areas of the map are inaccessible for a period of time. Typically this is done via doors which are locked until a set time passes (func_door in ExtraEntitesMod), but also can be done with teleporters (also ExtraEntitesMod) that are not enabled until a certain time. There is also a siege room directly adjacent to the hives from which marines can end the game if they survive long enough for the room to become accessible.
Each of these siege mechanics has problems in the NS2 game engine, primarily stemming from NS2's use of a navigation mesh and infestation / cysting mechanics.
--- Doors ---
Thus far, the only easy option for timed doors is to use func_door and logic_timer from ExtraEntitesMod. The door is perfect for stopping players, but for commanders, the doors may as well not exist. Aliens can cyst right past them, and drifters, MACs, and ARCs can roll through a locked door almost as if it wasn't even there. Investigation with the nav_debug command reveals that the locked doors only partially and somewhat inconsistently block NS2's navigation mesh, which explains why AI units can pass unhindered. Some doors block the nav mesh when locked, but not when unlocked. This prevents AI units from passing a locked door but allows them passage when the door is unlocked.
--- Teleporters ---
Teleporters are great for maps with an unconventional structure, and you might think they would be the solution for ARCs entering the siege room early, but they aren't. NS2 requires the navigation mesh to reach and fill each room where you intend to build or send AI units, so each room also needs an unbroken ground-based path! That means AI units can get in!
--- Getting into the siege room early ---
Infestation grows in a circular area around hives and cysts. It does not apparently care about walls and will gladly spread from the hive room directly into the adjacent siege room! The only way I have found to stop aliens from building on this infestation in the siege room is to make the susceptible areas non-buildable in the map editor. Unfortunately, you can't order an ARC onto an unbuildable area! So you need at least one buildable area in the siege room near enough the hives that you can send ARCs there to deploy them yet small enough and close enough to a wall that aliens can't build on it.
Further, cyst chaining ignores line of sight if there is not a reasonably short unbroken path between the new cyst and the nearest already-connected cyst. In many cases, this means you can't put a siege room within cysting range of any other buildable location.
--- How to avoid these issues ---
If you build a siege map, build the basic layout EARLY and test thoroughly to ensure aliens can't build in the siege room and that all the doors block AI units when they should. You may find that significant changes are needed!
Comments
The other major difference with a siege map is just how strong ARCs are. If a marine teams spends 15 min making ARCs, and sends all of them at once into a hive room with 3 hives, they'll destroy everything before the alien team can kill them. This was very different with static siege turrets.
But you'd still be rather limited in the positioning of the hive and siege rooms. In my newest map, ns2_veilsiege (modified from ns2_veil), I tried a "detached from the world" siege room (what a mistake!) and it took a good 6 hours of experimentation to make it halfway viable and at the same time immune to infestation by the alien commander.
in the last version it worked with just adding obstacle,
but the path actually seems to ignore it.