From d26eb2d5a3b33ef111bcf27d7f5b34bfee0d8438 Mon Sep 17 00:00:00 2001
From: teknomunk <teknomunk@protonmail.com>
Date: Tue, 24 Sep 2024 07:00:03 -0500
Subject: [PATCH] Add hook to allow piercing enchantment to be implemented

---
 mods/ITEMS/vl_projectile/api.md   |  5 ++++-
 mods/ITEMS/vl_projectile/init.lua | 12 ++++++++++--
 2 files changed, 14 insertions(+), 3 deletions(-)

diff --git a/mods/ITEMS/vl_projectile/api.md b/mods/ITEMS/vl_projectile/api.md
index da0dbcfc5..b77099cad 100644
--- a/mods/ITEMS/vl_projectile/api.md
+++ b/mods/ITEMS/vl_projectile/api.md
@@ -17,7 +17,10 @@ Arguments:
   * `damages_players`: if true, the projectile will deal damage to players.
   * `damage_groups`: damage group information to use for `punch()`. May be a function of type `function(projectile, entity_def, projectile_def, obj)`
                      that returns dynamic damange group information.
-  * `allow_punching`: will the projectile punch entities it collides with. May be a function of type `function(projectile, entity_def, projectile_def, obj)`.
+  * `allow_punching`: will the projectile punch entities it collides with. May be either a boolean or a function of type `function(projectile, entity_def, projectile_def, obj)`.
+  * `survive_collision`: will the projectile surive collisions. May be either a boolean or a fnction of type `function(projectile, entity_def, projectile_def, type, ...)`.
+    * If `type` is "node" then the additional parameters `node, node_def` will be provided.
+    * If `type` is "entity" then the additional parameter `objet` will be provided.
   * `behaviors`: a list of behavior callbacks that define the projectile's behavior. This mod provides the following
                  behaviors: `vl_projectiles.collides_with_solids`, `vl_projectiles.collides_with_entities` and `vl_projectiles.raycast_collides_with_entities`
   * `sounds`: sounds for this projectile. All fields take a table with three parameters corresponding to the
diff --git a/mods/ITEMS/vl_projectile/init.lua b/mods/ITEMS/vl_projectile/init.lua
index 0569e954f..3174c192b 100644
--- a/mods/ITEMS/vl_projectile/init.lua
+++ b/mods/ITEMS/vl_projectile/init.lua
@@ -240,7 +240,11 @@ function mod.collides_with_solids(self, dtime, entity_def, projectile_def)
 	end
 
 	-- Normally objects should be removed on collision with solids
-	if not projectile_def.survive_collision then
+	local survive_collision = projectile_def.survive_collision
+	if type(survive_collision) == "function" then
+		survive_collision = survive_collision(self, entity_def, projectile_def, "node", node, node_def)
+	end
+	if not survive_collision then
 		self._removed = true
 		self.object:remove()
 	end
@@ -326,7 +330,11 @@ local function handle_entity_collision(self, entity_def, projectile_def, object)
 	end
 
 	-- Normally objects should be removed on collision with entities
-	if not projectile_def.survive_collision then
+	local survive_collision = projectile_def.survive_collision
+	if type(survive_collision) == "function" then
+		survive_collision = survive_collision(self, entity_def, projectile_def, "entity", object)
+	end
+	if not survive_collision then
 		self._removed = true
 		self.object:remove()
 	end