mirror of
https://github.com/sbrl/Minetest-WorldEditAdditions.git
synced 2024-12-23 20:15:02 +00:00
100 lines
3.6 KiB
Lua
100 lines
3.6 KiB
Lua
local wea_c = worldeditadditions_core
|
|
local Vector3 = wea_c.Vector3
|
|
|
|
--- Generates a torus shape at the given position with the given parameters.
|
|
-- @param position Vector The position at which to generate the torus.
|
|
-- @param major_radius number The major radius of the torus - i.e. the distance from the middle to the ring.
|
|
-- @param minor_radius number The minor radius of the torus - i.e. the radius fo the ring itself.
|
|
-- @param target_node string The name of the target node to generate the torus with.
|
|
-- @param axes=xz string|nil The axes upon which the torus should lay flat.
|
|
-- @param hollow=false boolean Whether the generated torus should be hollow or not.
|
|
-- @returns number The number of nodes replaced.
|
|
function worldeditadditions.torus(position, major_radius, minor_radius, target_node, axes, hollow)
|
|
local matrix = {x='yz', y='xz', z='xy'}
|
|
if type(axes) ~= "string" then axes = "xz" end
|
|
if #axes == 1 and axes:match('[xyz]') then axes = matrix[axes] end
|
|
|
|
-- position = { x, y, z }
|
|
local total_radius = major_radius + minor_radius
|
|
local inner_minor_radius = minor_radius - 2
|
|
local major_radius_sq = major_radius*major_radius
|
|
local minor_radius_sq = minor_radius*minor_radius
|
|
local inner_minor_radius_sq = inner_minor_radius*inner_minor_radius
|
|
|
|
-- Fetch the nodes in the specified area
|
|
-- OPTIMIZE: We should be able to calculate a more efficient box-area here
|
|
-- This is complicated by the multiple possible axes though
|
|
local manip, area = worldedit.manip_helpers.init_radius(position, total_radius)
|
|
local data = manip:get_data()
|
|
|
|
local node_id = minetest.get_content_id(target_node)
|
|
local node_id_air = minetest.get_content_id("air")
|
|
|
|
local stride_z, stride_y = area.zstride, area.ystride
|
|
|
|
local count = 0 -- The number of nodes replaced
|
|
|
|
local idx_z_base = area:index(position.x - total_radius, position.y - total_radius, position.z - total_radius) -- initial z offset
|
|
for z = -total_radius, total_radius do
|
|
local z_sq = z*z
|
|
|
|
local idx_y_base = idx_z_base
|
|
for y = -total_radius, total_radius do
|
|
local y_sq = y*y
|
|
|
|
local i = idx_y_base
|
|
for x = -total_radius, total_radius do
|
|
local x_sq = x*x
|
|
|
|
local sq = Vector3.new(x_sq, y_sq, z_sq)
|
|
|
|
-- Default: xy
|
|
if axes == "xz" then
|
|
sq.x, sq.y, sq.z = sq.x, sq.z, sq.y
|
|
elseif axes == "yz" then
|
|
sq.x, sq.y, sq.z = sq.y, sq.z, sq.x
|
|
end
|
|
|
|
-- (x^2+y^2+z^2-(a^2+b^2))^2-4 a b (b^2-z^2)
|
|
-- Where:
|
|
-- (x, y, z) is the point
|
|
-- a is the major radius (centre of the ring to the centre of the torus)
|
|
-- b is the minor radius (radius of the ring)
|
|
local comp_a = (sq.x+sq.y+sq.z - (major_radius_sq+minor_radius_sq))
|
|
local test_value = comp_a*comp_a - 4*major_radius*minor_radius*(minor_radius_sq-sq.z)
|
|
|
|
-- If we're inside the torus, then fill it in
|
|
if test_value <= 1 then
|
|
local place_ok = not hollow;
|
|
|
|
if not place_ok then
|
|
-- It must be hollow! Do some additional calculations.
|
|
local inner_comp_a = (sq.x+sq.y+sq.z - (major_radius_sq+inner_minor_radius_sq))
|
|
local inner_test_value = inner_comp_a*inner_comp_a - 4*major_radius*inner_minor_radius*(inner_minor_radius_sq-sq.z)
|
|
|
|
-- It's only ok to place it if it's outside our inner torus
|
|
place_ok = inner_test_value >= 0
|
|
end
|
|
|
|
if place_ok then
|
|
data[i] = node_id
|
|
count = count + 1
|
|
end
|
|
end
|
|
|
|
|
|
i = i + 1
|
|
end
|
|
idx_y_base = idx_y_base + stride_y
|
|
|
|
end
|
|
idx_z_base = idx_z_base + stride_z
|
|
|
|
end
|
|
|
|
|
|
-- Save the modified nodes back to disk & return
|
|
worldedit.manip_helpers.finish(manip, data)
|
|
|
|
return count
|
|
end
|