Add wearables API

mods/rgt_cosmetics/init.lua

@@ -3,6 +3,8 @@ rgt_cosmetics = {
 }
 local ns = rgt_cosmetics
 
+include "wearables.lua"
+
 --[[
     {
         name = "", -- Technical name

mods/rgt_cosmetics/wearables.lua

@@ -0,0 +1,118 @@
+
+local ns = rgt_cosmetics
+
+ns.wearables = {}
+
+--[[
+    {
+        name = "", -- Name of the wearable
+        attachments = { -- List of individual attachments managed by this wearable (in case one wearable involves multiple bones)
+            mesh = "", -- The wearable's mesh
+            textures = {"", ...}, -- The wearable's textures
+            bone = ", -- Name of the player bone to attach to
+            pos = <vector>, -- Attachment offset
+            rot = <vector>, -- Attachment rotation
+        }
+    }
+--]]
+function ns.register_wearable(def)
+    ns.wearables[def.name] = def
+end
+
+minetest.register_entity("rgt_cosmetics:wearable", {
+    initial_properties = {
+        visual = "mesh",
+        pointable = false,
+        static_save = false
+    },
+    on_activate = function(e)
+        e.object:set_armor_groups{immortal = 1}
+    end,
+    represent = function(e, form)
+        e.form = form
+        e.object:set_properties {
+            mesh = form.mesh,
+            textures = form.textures
+        }
+        e.object:set_attach(e.owner.object, form.bone, form.pos, form.rot)
+        if form.animation then
+            e.object:set_animation(form.animation, form.animation.frame_speed or 1, nil, form.animation.loop)
+        end
+    end,
+    on_deactivate = function(e, removed)
+        -- Reactivate immediately if we were not explicitly marked for removal.
+        -- This is to prevent wearables from being lost to unloading, and to
+        -- minimize interference from mods that might try to remove objects
+        -- they shouldn't try to remove. Note that we must check get_pos() here
+        -- because, since on_leaveplayer is called _after_ mapblock unloading,
+        -- the entity may otherwise attempt to reactivate itself when its
+        -- owner has left the game (causing a crash).
+        if not e._remove and e.owner.object:get_pos() then
+            e.owner.wearing[e.form.name][e.index] = ns.apply_wearable_part(e.owner, e.form, e.index)
+        end
+    end
+})
+
+function ns.apply_wearable_part(m, w, i)
+    local obj = minetest.add_entity(m.pos, "rgt_cosmetics:wearable")
+    local e = obj:get_luaentity()
+    e.owner = m
+    e.index = i
+    e:represent(w)
+    return obj
+end
+
+function ns.apply_wearable(m, wearable)
+    local w = type(wearable) == "string" and ns.wearables[wearable] or wearable
+    -- Do nothing if we're already wearing this.
+    if m.wearing[w.name] then return end
+    local item = {}
+    for i, x in ipairs(w.attachments) do
+        x.name = w.name
+        item[i] = ns.apply_wearable_part(m, x, i)
+    end
+    m.wearing[w.name] = item
+end
+
+function ns.remove_wearable(m, wearable)
+    if m.wearing[wearable] then
+        for _, x in pairs(m.wearing[wearable]) do
+            -- Explicitly mark the object for removal.
+            x:get_luaentity()._remove = true
+            x:remove()
+        end
+        m.wearing[wearable] = nil
+    end
+end
+
+minetest.register_on_leaveplayer(function(p)
+    local m = rgt.players[p:get_player_name()]
+    for k in pairs(m.wearing) do
+        ns.remove_wearable(m, k)
+    end
+end)
+
+ns.register_wearable {
+    name = "top_hat",
+    attachments = {
+        {
+            mesh = "rgt_top_hat.gltf",
+            textures = {"rgt_top_hat.png"},
+            bone = "Head",
+            pos = vector.new(0, 3.5, 0),
+            rot = vector.new(0, 0, 0)
+        }
+    }
+}
+
+minetest.register_chatcommand("wear", {
+    func = function(name, args)
+        ns.apply_wearable(rgt.players[name], args)
+    end
+})
+
+minetest.register_chatcommand("unwear", {
+    func = function(name, args)
+        ns.remove_wearable(rgt.players[name], args)
+    end
+})