forked from VoxeLibre/VoxeLibre
399 lines
12 KiB
Lua
399 lines
12 KiB
Lua
--[[
|
|
Explosion API mod for Minetest (adapted to MineClone 2)
|
|
|
|
This mod is based on the Minetest explosion API mod, but has been changed
|
|
to have the same explosion mechanics as Minecraft and work with MineClone.
|
|
The computation-intensive parts of the mod has been optimized to allow for
|
|
larger explosions and faster world updating.
|
|
|
|
This mod was created by Elias Astrom <ryvnf@riseup.net> and is released
|
|
under the LGPLv2.1 license.
|
|
--]]
|
|
|
|
mcl_explosions = {}
|
|
|
|
local mod_death_messages = minetest.get_modpath("mcl_death_messages") ~= nil
|
|
local mod_fire = minetest.get_modpath("mcl_fire") ~= nil
|
|
local CONTENT_FIRE = minetest.get_content_id("mcl_fire:fire")
|
|
|
|
local S = minetest.get_translator("mcl_explosions")
|
|
|
|
-- Saved sphere explosion shapes for various radiuses
|
|
local sphere_shapes = {}
|
|
|
|
-- Saved node definitions in table using cid-keys for faster look-up.
|
|
local node_blastres = {}
|
|
local node_on_blast = {}
|
|
local node_walkable = {}
|
|
|
|
-- The step length for the rays (Minecraft uses 0.3)
|
|
local STEP_LENGTH = 0.3
|
|
|
|
-- How many rays to compute entity exposure to explosion
|
|
local N_EXPOSURE_RAYS = 16
|
|
|
|
minetest.register_on_mods_loaded(function()
|
|
-- Store blast resistance values by content ids to improve performance.
|
|
for name, def in pairs(minetest.registered_nodes) do
|
|
local id = minetest.get_content_id(name)
|
|
node_blastres[id] = def._mcl_blast_resistance or 0
|
|
node_on_blast[id] = def.on_blast
|
|
node_walkable[id] = def.walkable
|
|
end
|
|
end)
|
|
|
|
-- Compute the rays which make up a sphere with radius. Returns a list of rays
|
|
-- which can be used to trace explosions. This function is not efficient
|
|
-- (especially for larger radiuses), so the generated rays for various radiuses
|
|
-- should be cached and reused.
|
|
--
|
|
-- Should be possible to improve by using a midpoint circle algorithm multiple
|
|
-- times to create the sphere, currently uses more of a brute-force approach.
|
|
local function compute_sphere_rays(radius)
|
|
local rays = {}
|
|
local sphere = {}
|
|
|
|
for i=1, 2 do
|
|
for y = -radius, radius do
|
|
for z = -radius, radius do
|
|
for x = -radius, 0, 1 do
|
|
local d = x * x + y * y + z * z
|
|
if d <= radius * radius then
|
|
local pos = { x = x, y = y, z = z }
|
|
sphere[minetest.hash_node_position(pos)] = pos
|
|
break
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
for i=1,2 do
|
|
for x = -radius, radius do
|
|
for z = -radius, radius do
|
|
for y = -radius, 0, 1 do
|
|
local d = x * x + y * y + z * z
|
|
if d <= radius * radius then
|
|
local pos = { x = x, y = y, z = z }
|
|
sphere[minetest.hash_node_position(pos)] = pos
|
|
break
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
for i=1,2 do
|
|
for x = -radius, radius do
|
|
for y = -radius, radius do
|
|
for z = -radius, 0, 1 do
|
|
local d = x * x + y * y + z * z
|
|
if d <= radius * radius then
|
|
local pos = { x = x, y = y, z = z }
|
|
sphere[minetest.hash_node_position(pos)] = pos
|
|
break
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
for _, pos in pairs(sphere) do
|
|
rays[#rays + 1] = vector.normalize(pos)
|
|
end
|
|
|
|
return rays
|
|
end
|
|
|
|
-- Add particles from explosion
|
|
--
|
|
-- Parameters:
|
|
-- pos - The position of the explosion
|
|
-- radius - The radius of the explosion
|
|
local function add_particles(pos, radius)
|
|
minetest.add_particlespawner({
|
|
amount = 64,
|
|
time = 0.125,
|
|
minpos = pos,
|
|
maxpos = pos,
|
|
minvel = {x = -radius, y = -radius, z = -radius},
|
|
maxvel = {x = radius, y = radius, z = radius},
|
|
minacc = vector.new(),
|
|
maxacc = vector.new(),
|
|
minexptime = 0.5,
|
|
maxexptime = 1.0,
|
|
minsize = radius * 0.5,
|
|
maxsize = radius * 1.0,
|
|
texture = "tnt_smoke.png",
|
|
})
|
|
end
|
|
|
|
-- Traces the rays of an explosion, and updates the environment.
|
|
--
|
|
-- Parameters:
|
|
-- pos - Where the rays in the explosion should start from
|
|
-- strength - The strength of each ray
|
|
-- raydirs - The directions for each ray
|
|
-- radius - The maximum distance each ray will go
|
|
-- drop_chance - The chance that destroyed nodes will drop their items
|
|
-- fire - If true, 1/3 of destroyed nodes become fire
|
|
-- puncher - object that punches other objects (optional)
|
|
--
|
|
-- Note that this function has been optimized, it contains code which has been
|
|
-- inlined to avoid function calls and unnecessary table creation. This was
|
|
-- measured to give a significant performance increase.
|
|
local function trace_explode(pos, strength, raydirs, radius, drop_chance, fire, puncher, creative_enabled)
|
|
local vm = minetest.get_voxel_manip()
|
|
|
|
local emin, emax = vm:read_from_map(vector.subtract(pos, radius),
|
|
vector.add(pos, radius))
|
|
local emin_x = emin.x
|
|
local emin_y = emin.y
|
|
local emin_z = emin.z
|
|
|
|
local ystride = (emax.x - emin_x + 1)
|
|
local zstride = ystride * (emax.y - emin_y + 1)
|
|
local pos_x = pos.x
|
|
local pos_y = pos.y
|
|
local pos_z = pos.z
|
|
|
|
local area = VoxelArea:new {
|
|
MinEdge = emin,
|
|
MaxEdge = emax
|
|
}
|
|
local data = vm:get_data()
|
|
local destroy = {}
|
|
|
|
-- Trace rays for environment destruction
|
|
for i = 1, #raydirs do
|
|
local rpos_x = pos.x
|
|
local rpos_y = pos.y
|
|
local rpos_z = pos.z
|
|
local rdir_x = raydirs[i].x
|
|
local rdir_y = raydirs[i].y
|
|
local rdir_z = raydirs[i].z
|
|
local rstr = (0.7 + math.random() * 0.6) * strength
|
|
|
|
for r = 0, math.ceil(radius * (1.0 / STEP_LENGTH)) do
|
|
local npos_x = math.floor(rpos_x + 0.5)
|
|
local npos_y = math.floor(rpos_y + 0.5)
|
|
local npos_z = math.floor(rpos_z + 0.5)
|
|
local idx = (npos_z - emin_z) * zstride + (npos_y - emin_y) * ystride +
|
|
npos_x - emin_x + 1
|
|
|
|
local cid = data[idx]
|
|
local br = node_blastres[cid]
|
|
local hash = minetest.hash_node_position({x=npos_x, y=npos_y, z=npos_z})
|
|
|
|
rpos_x = rpos_x + STEP_LENGTH * rdir_x
|
|
rpos_y = rpos_y + STEP_LENGTH * rdir_y
|
|
rpos_z = rpos_z + STEP_LENGTH * rdir_z
|
|
|
|
rstr = rstr - 0.75 * STEP_LENGTH - (br + 0.3) * STEP_LENGTH
|
|
|
|
if rstr <= 0 then
|
|
break
|
|
end
|
|
|
|
if cid ~= minetest.CONTENT_AIR then
|
|
destroy[hash] = idx
|
|
end
|
|
end
|
|
end
|
|
|
|
-- Entities in radius of explosion
|
|
local punch_radius = 2 * strength
|
|
local objs = minetest.get_objects_inside_radius(pos, punch_radius)
|
|
|
|
-- Trace rays for entity damage
|
|
for _, obj in pairs(objs) do
|
|
local ent = obj:get_luaentity()
|
|
|
|
-- Ignore items to lower lag
|
|
if obj:is_player() or (ent and ent.name ~= '__builtin.item') then
|
|
local opos = obj:get_pos()
|
|
local collisionbox = nil
|
|
|
|
if obj:is_player() then
|
|
collisionbox = { -0.3, 0.0, -0.3, 0.3, 1.77, 0.3 }
|
|
elseif ent.name then
|
|
local def = minetest.registered_entities[ent.name]
|
|
collisionbox = def.collisionbox
|
|
end
|
|
|
|
if collisionbox then
|
|
-- Create rays from random points in the collision box
|
|
local x1 = collisionbox[1] * 2
|
|
local y1 = collisionbox[2] * 2
|
|
local z1 = collisionbox[3] * 2
|
|
local x2 = collisionbox[4] * 2
|
|
local y2 = collisionbox[5] * 2
|
|
local z2 = collisionbox[6] * 2
|
|
local x_len = math.abs(x2 - x1)
|
|
local y_len = math.abs(y2 - y1)
|
|
local z_len = math.abs(z2 - z1)
|
|
|
|
-- Move object position to the center of its bounding box
|
|
opos.x = opos.x + x1 + x2
|
|
opos.y = opos.y + y1 + y2
|
|
opos.z = opos.z + z1 + z2
|
|
|
|
-- Count number of rays from collision box which are unobstructed
|
|
local count = N_EXPOSURE_RAYS
|
|
|
|
for i = 1, N_EXPOSURE_RAYS do
|
|
local rpos_x = opos.x + math.random() * x_len - x_len / 2
|
|
local rpos_y = opos.y + math.random() * y_len - y_len / 2
|
|
local rpos_z = opos.z + math.random() * z_len - z_len / 2
|
|
local rdir_x = pos.x - rpos_x
|
|
local rdir_y = pos.y - rpos_y
|
|
local rdir_z = pos.z - rpos_z
|
|
local rdir_len = math.hypot(rdir_x, math.hypot(rdir_y, rdir_z))
|
|
rdir_x = rdir_x / rdir_len
|
|
rdir_y = rdir_y / rdir_len
|
|
rdir_z = rdir_z / rdir_len
|
|
|
|
for i=0, rdir_len / STEP_LENGTH do
|
|
rpos_x = rpos_x + rdir_x * STEP_LENGTH
|
|
rpos_y = rpos_y + rdir_y * STEP_LENGTH
|
|
rpos_z = rpos_z + rdir_z * STEP_LENGTH
|
|
local npos_x = math.floor(rpos_x + 0.5)
|
|
local npos_y = math.floor(rpos_y + 0.5)
|
|
local npos_z = math.floor(rpos_z + 0.5)
|
|
local idx = (npos_z - emin_z) * zstride + (npos_y - emin_y) * ystride +
|
|
npos_x - emin_x + 1
|
|
|
|
|
|
local cid = data[idx]
|
|
local walkable = node_walkable[cid]
|
|
|
|
if walkable then
|
|
count = count - 1
|
|
break
|
|
end
|
|
end
|
|
end
|
|
|
|
-- Punch entity with damage depending on explosion exposure and
|
|
-- distance to explosion
|
|
local exposure = count / N_EXPOSURE_RAYS
|
|
local punch_vec = vector.subtract(opos, pos)
|
|
local punch_dir = vector.normalize(punch_vec)
|
|
local impact = (1 - vector.length(punch_vec) / punch_radius) * exposure
|
|
if impact < 0 then
|
|
impact = 0
|
|
end
|
|
local damage = math.floor((impact * impact + impact) * 7 * strength + 1)
|
|
if mod_death_messages and obj:is_player() then
|
|
mcl_death_messages.player_damage(obj, S("@1 was caught in an explosion.", obj:get_player_name()))
|
|
end
|
|
local source = puncher
|
|
if not source then
|
|
source = obj
|
|
end
|
|
obj:punch(source, 10, { damage_groups = { full_punch_interval = 1,
|
|
fleshy = damage, knockback = impact * 20.0 } }, punch_dir)
|
|
|
|
if obj:is_player() then
|
|
obj:add_player_velocity(vector.multiply(punch_dir, impact * 20))
|
|
elseif ent.tnt_knockback then
|
|
obj:add_velocity(vector.multiply(punch_dir, impact * 20))
|
|
end
|
|
end
|
|
end
|
|
end
|
|
|
|
local airs, fires = {}, {}
|
|
|
|
-- Remove destroyed blocks and drop items
|
|
for hash, idx in pairs(destroy) do
|
|
local do_drop = not creative_enabled and math.random() <= drop_chance
|
|
local on_blast = node_on_blast[data[idx]]
|
|
local remove = true
|
|
|
|
if do_drop or on_blast ~= nil then
|
|
local npos = minetest.get_position_from_hash(hash)
|
|
if on_blast ~= nil then
|
|
on_blast(npos, 1.0)
|
|
remove = false
|
|
else
|
|
local name = minetest.get_name_from_content_id(data[idx])
|
|
local drop = minetest.get_node_drops(name, "")
|
|
|
|
for _, item in ipairs(drop) do
|
|
if type(item) ~= "string" then
|
|
item = item:get_name() .. item:get_count()
|
|
end
|
|
minetest.add_item(npos, item)
|
|
end
|
|
end
|
|
end
|
|
if remove then
|
|
if mod_fire and fire and math.random(1, 3) == 1 then
|
|
table.insert(fires, minetest.get_position_from_hash(hash))
|
|
else
|
|
table.insert(airs, minetest.get_position_from_hash(hash))
|
|
end
|
|
end
|
|
end
|
|
-- We use bulk_set_node instead of LVM because we want to have on_destruct and
|
|
-- on_construct being called
|
|
if #airs > 0 then
|
|
minetest.bulk_set_node(airs, {name="air"})
|
|
end
|
|
if #fires > 0 then
|
|
minetest.bulk_set_node(fires, {name="mcl_fire:fire"})
|
|
end
|
|
-- Update falling nodes
|
|
for a=1, #airs do
|
|
local p = airs[a]
|
|
minetest.check_for_falling({x=p.x, y=p.y+1, z=p.z})
|
|
end
|
|
for f=1, #fires do
|
|
local p = fires[f]
|
|
minetest.check_for_falling({x=p.x, y=p.y+1, z=p.z})
|
|
end
|
|
|
|
-- Log explosion
|
|
minetest.log('action', 'Explosion at ' .. minetest.pos_to_string(pos) ..
|
|
' with strength ' .. strength .. ' and radius ' .. radius)
|
|
|
|
end
|
|
|
|
-- Create an explosion with strength at pos.
|
|
--
|
|
-- Parameters:
|
|
-- pos - The position where the explosion originates from
|
|
-- strength - The blast strength of the explosion (a TNT explosion uses 4)
|
|
-- info - Table containing information about explosion.
|
|
-- puncher - object that is reported as source of punches/damage (optional)
|
|
--
|
|
-- Values in info:
|
|
-- drop_chance - If specified becomes the drop chance of all nodes in the
|
|
-- explosion (defaults to 1.0 / strength)
|
|
-- no_sound - If true then the explosion will not play a sound
|
|
-- no_particle - If true then the explosion will not create particles
|
|
-- fire - If true, 1/3 nodes become fire (default: false)
|
|
function mcl_explosions.explode(pos, strength, info, puncher)
|
|
-- The maximum blast radius (in the air)
|
|
local radius = math.ceil(1.3 * strength / (0.3 * 0.75) * 0.3)
|
|
|
|
if not sphere_shapes[radius] then
|
|
sphere_shapes[radius] = compute_sphere_rays(radius)
|
|
end
|
|
local shape = sphere_shapes[radius]
|
|
|
|
local creative_enabled = minetest.is_creative_enabled("")
|
|
trace_explode(pos, strength, shape, radius, (info and info.drop_chance) or 1 / strength, info.fire == true, puncher, creative_enabled)
|
|
|
|
if not (info and info.no_sound) then
|
|
add_particles(pos, radius)
|
|
end
|
|
if not (info and info.no_particle) then
|
|
minetest.sound_play("tnt_explode", {
|
|
pos = pos, gain = 1.0,
|
|
max_hear_distance = strength * 16
|
|
}, true)
|
|
end
|
|
end
|