Make relic carts visible for all civs when they are gathered.

mods/ids.py

@@ -435,3 +435,5 @@
 TYPE_GARRISON = 3
 ATTR_MODIFIER_MULTIPLY = 5
 ATTR_WORK_RATE = 13
+
+TYPE_UNIT_VISION_GRANT_EFFECT = 204

mods/rewarding_snipes.py

@@ -4,12 +4,69 @@
 from genieutils.datfile import DatFile
 
 from mods.ids import KING, RELIC_CART, TYPE_POPULATION_HEADROOM, TYPE_GIVE_AND_TAKE, \
-    TYPE_BONUS_POPULATION_CAP
+    TYPE_BONUS_POPULATION_CAP, TYPE_UNIT_VISION_GRANT_EFFECT, TYPE_RESOURCE_MODIFIER
+
+from genieutils.effect import EffectCommand, Effect
+
+from genieutils.tech import Tech, ResearchResourceCost, ResearchLocation
+
 from mods.util import clone
 
 NAME = 'rewarding-snipes'
 
 
+def add_tech_for_relic_cart_vision_to_each_civ(data: DatFile, relic_cart_unit_id: int, version: str):
+    effect_command = EffectCommand(
+        type=TYPE_RESOURCE_MODIFIER,
+        a=TYPE_UNIT_VISION_GRANT_EFFECT,
+        b=0,  # mode
+        c=-1,
+        d=-(relic_cart_unit_id)  # negative unit ID to grant vision always and not just on creation.
+    )
+
+    effect = Effect(
+        name='Give Relic Cart Vision to Civ',
+        effect_commands=[effect_command]
+    )
+    effect_id = len(data.effects)
+    data.effects.append(effect)
+
+    for civ_id, civ in enumerate(data.civs):
+        tech = Tech(
+            required_techs=(-1, -1, -1, -1, -1, -1),
+            resource_costs=(
+                ResearchResourceCost(type=-1, amount=0, flag=0),
+                ResearchResourceCost(type=-1, amount=0, flag=0),
+                ResearchResourceCost(type=-1, amount=0, flag=0),
+            ),
+            required_tech_count=0,
+            civ=civ_id,
+            full_tech_mode=0,
+            research_location=-1,  # no specific location
+            language_dll_name=0,
+            language_dll_description=0,
+            research_time=0,
+            effect_id=effect_id,
+            type=0,
+            icon_id=-1,
+            button_id=1,
+            language_dll_help=0,
+            language_dll_tech_tree=0,
+            hot_key=0,
+            name='Grant Civ Relic Cart Vision',
+            repeatable=1,
+            research_locations=[
+                ResearchLocation(
+                    location_id=-1,
+                    research_time=0,
+                    button_id=0,
+                    hot_key_id=-1,
+                )
+            ]
+        )
+        logging.info(f'Adding relic cart vision tech for civ {civ.name} with id {len(data.techs)}')
+        data.techs.append(tech)
+
 def clone_and_patch_relic_cart(civ: Civ, version: str):
     clone_unit_id = len(civ.units)
     cloned_unit = clone(civ.units[RELIC_CART], version)
@@ -39,6 +96,8 @@ def patch_kings(data: DatFile):
         king.blood_unit_id = relic_cart_id  # use blood unit so it does not conflict with exploding kings
         logging.info(f'Patched king blood unit for civ {civ.name}')
 
+    add_tech_for_relic_cart_vision_to_each_civ(data, relic_cart_id, data.version)
+
 
 def mod(data: DatFile):
     patch_kings(data)