implement actual items dropping

res/content/base/scripts/components/drop.lua

@@ -5,6 +5,7 @@ local rig = entity.modeltree
 inair = true
 ready = false
 
+local item = ARGS.item
 
 local rotation = mat4.rotate({0, 1, 0}, math.random() * 360)
 mat4.rotate(rotation, {1, 0, 0}, math.random() * 360, rotation)
@@ -24,7 +25,7 @@ end
 function on_trigger_enter(index, oid)
     if ready and oid == 0 then
         entity:despawn()
-        inventory.add(player.get_inventory(oid), item.index("base:stone.item"), 1)
+        inventory.add(player.get_inventory(oid), item.id, item.count)
         audio.play_sound_2d("events/pickup", 0.5, 0.8+math.random()*0.4, "regular")
     end
 end

res/content/base/scripts/hud.lua

@@ -3,19 +3,22 @@ local DROP_INIT_VEL = {0, 3, 0}
 
 function on_hud_open()
     input.add_callback("player.drop", function ()
-        for i=1,80 do
-            local pid = hud.get_player()
-            local pvel = {player.get_vel(pid)}
-            local ppos = vec3.add({player.get_pos(pid)}, {0, 0.7, 0})
-            local throw_force = vec3.mul(vec3.add(player.get_dir(pid), 
-            {
-                (math.random() - 0.5) * 1,
-                (math.random() - 0.5) * 1,
-                (math.random() - 0.5) * 1
-            }), DROP_FORCE)
-
-            local drop = entities.spawn("base:drop", ppos)
-            drop.rigidbody:set_vel(vec3.add(throw_force, vec3.add(pvel, DROP_INIT_VEL)))
+        local pid = hud.get_player()
+        local invid, slot = player.get_inventory(pid)
+        local itemid, itemcount = inventory.get(invid, slot)
+        if itemid == 0 then
+            return
         end
+        inventory.set(invid, slot, itemid, itemcount-1)
+
+        local pvel = {player.get_vel(pid)}
+        local ppos = vec3.add({player.get_pos(pid)}, {0, 0.7, 0})
+        local throw_force = vec3.mul(player.get_dir(pid), DROP_FORCE)
+
+        local drop = entities.spawn("base:drop", ppos, {item={
+            id=itemid,
+            count=1
+        }})
+        drop.rigidbody:set_vel(vec3.add(throw_force, vec3.add(pvel, DROP_INIT_VEL)))
     end)
 end

src/items/ItemStack.cpp

@@ -12,6 +12,9 @@ ItemStack::ItemStack(itemid_t item, itemcount_t count) : item(item), count(count
 void ItemStack::set(const ItemStack& item) {
     this->item = item.item;
     this->count = item.count;
+    if (count == 0) {
+        this->item = 0;
+    }
 }
 
 bool ItemStack::accepts(const ItemStack& other) const {

src/logic/scripting/lua/libinventory.cpp

@@ -32,7 +32,7 @@ static std::shared_ptr<Inventory> get_inventory(int64_t id, int arg) {
 }
 
 static void validate_slotid(int slotid, Inventory* inv) {
-    if (slotid < 0 || uint64_t(slotid) >= inv->size()) {
+    if (static_cast<size_t>(slotid) >= inv->size()) {
         throw std::runtime_error("slot index is out of range [0..inventory.size(invid)]");
     }
 }