diff options
Diffstat (limited to 'display.lua')
-rw-r--r-- | display.lua | 239 |
1 files changed, 239 insertions, 0 deletions
diff --git a/display.lua b/display.lua new file mode 100644 index 0000000..a8cee66 --- /dev/null +++ b/display.lua @@ -0,0 +1,239 @@ +--[[ + 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/>. +--]] + +-- 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 + +-- Maximum entity position relative to the node pos +local max_entity_pos = 1.5 + +-- Miscelaneous values depending on wallmounted param2 +local wallmounted_values = { + [2]={dx=-1, dz=0, rx=0, rz=-1, yaw=-math.pi/2}, + [3]={dx=1, dz=0, rx=0, rz=1, yaw=math.pi/2 }, + [4]={dx=0, dz=-1, rx=1, rz=0, yaw=0 }, + [5]={dx=0, dz=1, rx=-1, rz=0, yaw=math.pi } +} + +-- Miscelaneous values depending on facedir param2 +local facedir_values = { + [0]={dx=0, dz=-1, rx=1, rz=0, yaw=0 }, + [1]={dx=-1, dz=0, rx=0, rz=-1, yaw=-math.pi/2}, + [2]={dx=0, dz=1, rx=-1, rz=0, yaw=math.pi }, + [3]={dx=1, dz=0, rx=0, rz=1, yaw=math.pi/2 } +} + +-- dx/dy = depth vector, rx/ly = right vector, yaw = yaw of entity, +local function get_values(node) + local ndef = minetest.registered_nodes[node.name] + + if ndef then + local paramtype2 = ndef.paramtype2 + if paramtype2 == "wallmounted" or paramtype2 == "colorwallmounted" then + return wallmounted_values[node.param2 % 8] + elseif paramtype2 == "facedir" or paramtype2 == "colorfacedir" then + return facedir_values[node.param2 % 32] + end + 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, max_entity_pos)) do + local entity = objref:get_luaentity() + if entity and ndef.display_entities[entity.name] and + entity.nodepos and vector.equals(pos, entity.nodepos) then + if objrefs[entity.name] then + objref:remove() -- Remove duplicates + else + objrefs[entity.name] = objref + end + end + end + end + return objrefs +end + +local function clip_pos_prop(posprop) + if posprop then + return math.max(-max_entity_pos, math.min(max_entity_pos, 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, + minetest.serialize({ nodepos = pos })) + 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 + + +--- Entity update +function update_entity(entity) + if not entity then + return + end + + if not entity.nodepos then + entity.object:remove() -- Remove old/buggy entity + return + end + + local node = minetest.get_node(entity.nodepos) + local ndef = minetest.registered_nodes[node.name] + if ndef and ndef.display_entities and + ndef.display_entities[entity.name] and + ndef.display_entities[entity.name].on_display_update + then + -- Call on_display_update callback of a node for one of its display entities + ndef.display_entities[entity.name].on_display_update(entity.nodepos, + entity.object) + else + -- Display node has been removed, remove entity also + entity.object:remove() + end +end + +--- Force entity update +function display_api.update_entities(pos) + for _, objref in pairs(place_entities(pos)) do + update_entity(objref:get_luaentity()) + 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 = minetest.deserialize(staticdata) + if data and type(data) == "table" then + entity.nodepos = data.nodepos + end + entity.object:set_armor_groups({immortal=1}) + end + update_entity(entity) + end +end + +--- On_place callback for display_api items. +-- Does nothing more than preventing node from being placed on ceiling or ground +function display_api.on_place(itemstack, placer, pointed_thing, override_param2) + local ndef = itemstack:get_definition() + local above = pointed_thing.above + local under = pointed_thing.under + local dir = {x = under.x - above.x, y = 0, z = under.z - above.z} + + -- If item is not placed on a wall, use the player's view direction instead + if dir.x == 0 and dir.z == 0 then + dir = placer:get_look_dir() + dir.y = 0 + end + + local param2 = 0 + if ndef then + local paramtype2 = ndef.paramtype2 + if paramtype2 == "wallmounted" or paramtype2 == "colorwallmounted" then + param2 = minetest.dir_to_wallmounted(dir) + elseif paramtype2 == "facedir" or paramtype2 == "colorfacedir" then + param2 = minetest.dir_to_facedir(dir) + end + end + return minetest.item_place(itemstack, placer, pointed_thing, + param2 + (override_param2 or 0)) +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) + for _, objref in pairs(get_entities(pos)) do + objref:remove() + end +end + +-- On_rotate (screwdriver) callback for display_api items. Prevents invalid rotations and reorients entities. +function display_api.on_rotate(pos, node, user, _, new_param2) + node.param2 = new_param2 + if get_values(node) then + minetest.swap_node(pos, node) + 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_entities[entity_name] 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({ nodepos = self.nodepos }) + end, + }) + end +end + +minetest.register_lbm({ + label = "Update display_api entities", + name = "display_api:update_entities", + run_at_every_load = true, + nodenames = {"group:display_api", + "group:display_modpack_node", "group:display_lib_node"}, -- See deprecated(1) + action = function(pos, node) display_api.update_entities(pos) end, +}) |