display_modpack/display_api/init.lua

272 lines
8.6 KiB
Lua

--[[
display_api mod for Minetest - Library to add dynamic display
capabilities to nodes
(c) Pierre-Yves Rollo
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
--]]
display_api = {}
-- Prefered gap between node and entity
-- Entity positionment is up to mods but it is a good practice to use this
-- variable as spacing between entity and node
display_api.entity_spacing = 0.002
-- Miscelaneous values depending on wallmounted param2
local wallmounted_values = {
[0]={dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0}, -- Should never be used
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=1}, -- Should never be used
{dx=-1, dz=0, rx=0, rz=-1, yaw=-math.pi/2, rotate=5},
{dx=1, dz=0, rx=0, rz=1, yaw=math.pi/2, rotate=4},
{dx=0, dz=-1, rx=1, rz=0, yaw=0, rotate=2},
{dx=0, dz=1, rx=-1, rz=0, yaw=math.pi, rotate=3}
}
-- Miscelaneous values depending on facedir param2
local facedir_values = {
[0]={dx=0, dz=-1, rx=1, rz=0, yaw=0, rotate=1},
{dx=-1, dz=0, rx=0, rz=-1, yaw=-math.pi/2, rotate=2},
{dx=0, dz=1, rx=-1, rz=0, yaw=math.pi, rotate=3},
{dx=1, dz=0, rx=0, rz=1, yaw=math.pi/2, rotate=0},
-- Forbiden values :
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
{dx=0, dz=0, rx=0, rz=0, yaw=0, rotate=0},
}
-- dx/dy = depth vector, rx/ly = right vector, yaw = yaw of entity,
-- rotate = next facedir/wallmount on rotate
local function get_values(node)
local ndef = minetest.registered_nodes[node.name]
if ndef then
if ndef.paramtype2 == "wallmounted" then
return wallmounted_values[node.param2]
end
if ndef.paramtype2 == "facedir" then
return facedir_values[node.param2]
end
end
end
--- Checks if the object is related to the given position
local function check_entity_pos(pos, objref)
local real_pos = vector.round(objref:get_pos())
local pos_hash = objref:get_luaentity().pos
if pos_hash == nil then
return vector.equals(real_pos, vector.round(pos))
else
return vector.equals(minetest.get_position_from_hash(pos_hash), pos)
end
end
--- Gets the display entities attached with a node. Removes extra ones
local function get_entities(pos)
local objrefs = {}
local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
if ndef and ndef.display_entities then
for _, objref in ipairs(minetest.get_objects_inside_radius(pos, 1.5)) do
local entity = objref:get_luaentity()
if entity and ndef.display_entities[entity.name] and check_entity_pos(pos, objref) then
if objrefs[entity.name] then
objref:remove()
else
objrefs[entity.name] = objref
end
end
end
end
return objrefs
end
local function clip_pos_prop(posprop)
if posprop then
return math.max(-1.5, math.min(1.5, posprop))
else
return 0
end
end
--- (Create and) place display entities according to the node orientation
local function place_entities(pos)
local node = minetest.get_node(pos)
local ndef = minetest.registered_nodes[node.name]
local values = get_values(node)
local objrefs = get_entities(pos)
if values and ndef and ndef.display_entities then
for entity_name, props in pairs(ndef.display_entities) do
local depth = clip_pos_prop(props.depth)
local right = clip_pos_prop(props.right)
local top = clip_pos_prop(props.top)
if not objrefs[entity_name] then
objrefs[entity_name] = minetest.add_entity(pos, entity_name)
end
objrefs[entity_name]:setpos({
x = pos.x - values.dx * depth + values.rx * right,
y = pos.y - top,
z = pos.z - values.dz * depth + values.rz * right})
objrefs[entity_name]:setyaw(values.yaw)
end
end
return objrefs
end
--- Call on_display_update callback of a node for one of its display entities
local function call_node_on_display_update(pos, objref)
local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
local entity = objref:get_luaentity()
if ndef and ndef.display_entities and entity and ndef.display_entities[entity.name] then
ndef.display_entities[entity.name].on_display_update(pos, objref)
end
end
--- Force entity update
function display_api.update_entities(pos)
local objrefs = place_entities(pos)
for _, objref in pairs(objrefs) do
objref:get_luaentity().pos = minetest.hash_node_position(pos)
call_node_on_display_update(pos, objref)
end
end
--- On_activate callback for display_api entities. Calls on_display_update callbacks
--- of corresponding node for each entity.
function display_api.on_activate(entity, staticdata)
if entity then
if string.sub(staticdata, 1, string.len("return")) == "return" then
local data = core.deserialize(staticdata)
if data and type(data) == "table" then
entity.pos = data.pos
end
end
entity.object:set_armor_groups({immortal=1})
local pos
if entity.pos then
pos = minetest.get_position_from_hash(entity.pos)
else
pos = entity.object:getpos()
end
display_api.update_entities(pos)
end
end
--- On_place callback for display_api items. Does nothing more than preventing item
--- from being placed on ceiling or ground
function display_api.on_place(itemstack, placer, pointed_thing)
local ndef = itemstack:get_definition()
local above = pointed_thing.above
local under = pointed_thing.under
local dir = {x = under.x - above.x,
y = under.y - above.y,
z = under.z - above.z}
if ndef then
if ndef.paramtype2 == "wallmounted" then
local wdir = minetest.dir_to_wallmounted(dir)
if wdir == 0 or wdir == 1 then
dir = placer:get_look_dir()
dir.y = 0
wdir = minetest.dir_to_wallmounted(dir)
end
return minetest.item_place(itemstack, placer, pointed_thing, wdir)
else
return minetest.item_place(itemstack, placer, pointed_thing, minetest.dir_to_facedir(dir))
end
end
end
--- On_construct callback for display_api items. Creates entities and update them.
function display_api.on_construct(pos)
display_api.update_entities(pos)
end
--- On_destruct callback for display_api items. Removes entities.
function display_api.on_destruct(pos)
local objrefs = get_entities(pos)
for _, objref in pairs(objrefs) do
objref:remove()
end
end
-- On_rotate (screwdriver) callback for display_api items. Prevents axis rotation and reorients entities.
function display_api.on_rotate(pos, node, user, mode, new_param2)
if mode ~= 1 then return false end
local values = get_values(node)
if values then
minetest.swap_node(pos, {name = node.name, param1 = node.param1, param2 = values.rotate})
place_entities(pos)
return true
else
return false
end
end
--- Creates display entity with some fields and the on_activate callback
function display_api.register_display_entity(entity_name)
if not minetest.registered_entity then
minetest.register_entity(':'..entity_name, {
collisionbox = { 0, 0, 0, 0, 0, 0 },
visual = "upright_sprite",
textures = {},
on_activate = display_api.on_activate,
get_staticdata = function(self)
return minetest.serialize({
pos = self.pos,
})
end,
})
end
end
minetest.register_lbm({
label = "Update display_api entities",
name = "display_api:update_entities",
run_at_every_load = true,
nodenames = {"group:display_modpack_node", "group:display_lib_node"},
action = function(pos, node) display_api.update_entities(pos) end,
})
-- Compatibility
display_lib = display_api