fix: Prevented polylplasts from spawning above trench entrances.

prototypes/entity/coral.lua

@@ -130,13 +130,16 @@ data:extend {{
 }}
 
 -- totally not a slipstack
-local maraxsis_polylplast = table.deepcopy(data.raw.tree.slipstack)
-maraxsis_polylplast.name = "maraxsis-polylplast"
-maraxsis_polylplast.subgroup = "creatures"
-maraxsis_polylplast.order = "j-c[maraxsis-polylplast]"
-maraxsis_polylplast.autoplace = nil
-maraxsis_polylplast.minable.results = {
+local polylplast = table.deepcopy(data.raw.tree.slipstack)
+polylplast.name = "maraxsis-polylplast"
+polylplast.subgroup = "creatures"
+polylplast.order = "j-c[maraxsis-polylplast]"
+polylplast.autoplace = nil
+polylplast.minable.results = {
     {type = "item", name = "maraxsis-coral", amount_min = 20, amount_max = 25},
     {type = "item", name = "stone",          amount_min = 4,  amount_max = 6},
 }
-data:extend {maraxsis_polylplast}
+polylplast.maraxsis_buildability_rules = {water = true, dome = false, coral = true, trench = true, trench_entrance = false, trench_lava = false}
+polylplast.collision_mask.layers.ground_tile = nil
+polylplast.collision_mask.layers[maraxsis_trench_entrance_collision_mask] = true
+data:extend {polylplast}