diff options
Diffstat (limited to 'display_lib/init.lua')
| -rw-r--r-- | display_lib/init.lua | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/display_lib/init.lua b/display_lib/init.lua new file mode 100644 index 0000000..eaddfd3 --- /dev/null +++ b/display_lib/init.lua @@ -0,0 +1,156 @@ +-- Display lib mod by P.Y. Rollo +-- +-- License: WTFPL + +display_lib = {} + +-- Miscelaneous values depending on wallmounted param2 +local wallmounted_values = { + [0]={dx=0, dz=0, lx=0, lz=0, yaw=0, rotate=0}, -- Should never be used + {dx=1, dz=0, lx=0, lz=0, yaw=0, rotate=1}, -- Should never be used + {dx=1, dz=0, lx=0, lz=-1, yaw=-math.pi/2, rotate=4}, + {dx=-1, dz=0, lx=0, lz=1, yaw=math.pi/2, rotate=5}, + {dx=0, dz=1, lx=1, lz=0, yaw=0, rotate=3}, + {dx=0, dz=-1, lx=-1, lz=0, yaw=math.pi, rotate=2} +} + +--- 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, 0.5)) do + local entity = objref:get_luaentity() + if entity and ndef.display_entities[entity.name] 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(-0.5, math.min(0.5, 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 = wallmounted_values[node.param2] + local objrefs = get_entities(pos) + + if ndef and ndef.display_entities then + for entity_name, props in pairs(ndef.display_entities) do + local depth = clip_pos_prop(props.depth) + local top = clip_pos_prop(props.top) + local left = clip_pos_prop(props.left) + + 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.lx * left, + y = pos.y + top, + z = pos.z - values.dz * depth + values.lz * left}) + + 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_lib.update_entities(pos) + local objrefs = place_entities(pos) + for _, objref in pairs(objrefs) do + call_node_on_display_update(pos, objref) + end +end + +--- On_activate callback for display_lib entities. Calls on_display_update callbacks +--- of corresponding node for each entity. +function display_lib.on_activate(entity, staticdata) + if entity then + call_node_on_display_update(entity.object:getpos(), entity.object) + end +end + +--- On_place callback for display_lib items. Does nothing more than preventing item +--- from being placed on ceiling or ground +function display_lib.on_place(itemstack, placer, pointed_thing) + 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} + 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) +end + +--- On_construct callback for display_lib items. Creates entities and update them. +function display_lib.on_construct(pos) + display_lib.update_entities(pos) +end + +--- On_destruct callback for display_lib items. Removes entities. +function display_lib.on_destruct(pos) + local objrefs = get_entities(pos) + + for _, objref in pairs(objrefs) do + objref:remove() + end +end + + +-- On_rotate (screwdriver) callback for display_lib items. Prevents axis rotation and reorients entities. +function display_lib.on_rotate(pos, node, user, mode, new_param2) + if mode ~= screwdriver.ROTATE_FACE then return false end + + if wallmounted_values[node.param2] then + minetest.swap_node(pos, {name = node.name, param1 = node.param1, param2 = wallmounted_values[node.param2].rotate}) + place_entities(pos) + return true + else + return false + end +end + +--- Creates display entity with some fields and the on_activate callback +function display_lib.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_lib.on_activate, + }) + end +end + + + |