[CSM] add `on_item_use` (#5544)

builtin/client/register.lua

@@ -70,3 +70,4 @@ core.registered_on_formspec_input, core.register_on_formspec_input = make_regist
 core.registered_on_dignode, core.register_on_dignode = make_registration()
 core.registered_on_punchnode, core.register_on_punchnode = make_registration()
 core.registered_on_placenode, core.register_on_placenode = make_registration()
+core.registered_on_item_use, core.register_on_item_use = make_registration()

clientmods/preview/init.lua

@@ -22,6 +22,13 @@ core.register_on_placenode(function(pointed_thing, node)
 	return false
 end)
 
+core.register_on_item_use(function(itemstack, pointed_thing)
+	print("The local player used an item!")
+	print("pointed_thing :" .. dump(pointed_thing))
+	print("item = " .. itemstack:get_name())
+	return false
+end)
+
 -- This is an example function to ensure it's working properly, should be removed before merge
 core.register_on_receiving_chat_messages(function(message)
 	print("[PREVIEW] Received message " .. message)

doc/client_lua_api.md

@@ -669,6 +669,10 @@ Call these functions only at load time!
     * If any function returns true, the punch is ignored
 * `minetest.register_on_placenode(function(pointed_thing, node))`    
     * Called when a node has been placed
+* `minetest.register_on_item_use(func(item, pointed_thing))`
+    * Called when the local player uses an item.
+    * Newest functions are called first.
+    * If any function returns true, the item use is not sent to server.
 ### Sounds
 * `minetest.sound_play(spec, parameters)`: returns a handle
     * `spec` is a `SimpleSoundSpec`

src/game.cpp

@@ -3553,7 +3553,8 @@ void Game::processPlayerInteraction(f32 dtime, bool show_hud, bool show_debug)
 		runData.repeat_rightclick_timer = 0;
 
 	if (playeritem_def.usable && isLeftPressed()) {
-		if (getLeftClicked())
+		if (getLeftClicked() && (!client->moddingEnabled()
+				|| !client->getScript()->on_item_use(playeritem, pointed)))
 			client->interact(4, pointed);
 	} else if (pointed.type == POINTEDTHING_NODE) {
 		ToolCapabilities playeritem_toolcap =

src/script/cpp_api/s_client.cpp

@@ -207,6 +207,23 @@ bool ScriptApiClient::on_placenode(const PointedThing &pointed, const ItemDefini
 	return lua_toboolean(L, -1);
 }
 
+bool ScriptApiClient::on_item_use(const ItemStack &item, const PointedThing &pointed)
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	// Get core.registered_on_item_use
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "registered_on_item_use");
+
+	// Push data
+	LuaItemStack::create(L, item);
+	push_pointed_thing(L, pointed);
+
+	// Call functions
+	runCallbacks(2, RUN_CALLBACKS_MODE_OR);
+	return lua_toboolean(L, -1);
+}
+
 void ScriptApiClient::setEnv(ClientEnvironment *env)
 {
 	ScriptApiBase::setEnv(env);

src/script/cpp_api/s_client.h

@@ -26,6 +26,8 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "mapnode.h"
 #include "itemdef.h"
 #include "util/string.h"
+#include "util/pointedthing.h"
+#include "lua_api/l_item.h"
 
 #ifdef _CRT_MSVCP_CURRENT
 #include <cstdint>
@@ -54,6 +56,7 @@ public:
 	bool on_dignode(v3s16 p, MapNode node);
 	bool on_punchnode(v3s16 p, MapNode node);
 	bool on_placenode(const PointedThing &pointed, const ItemDefinition &item);
+	bool on_item_use(const ItemStack &item, const PointedThing &pointed);
 
 	void setEnv(ClientEnvironment *env);
 };