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local ft = {}
ft.__index = ft
function FSTile(w, h)
local self = {}
setmetatable(self, ft)
-- init stuff here
self.containers = {}
self.width = w
self.height = h
return self
end
-- cb_func(w, h, fs) -> fits? true/false
function ft:add_container(x, y, w, h, cb_func, data)
-- Change to min/max table
w = type(w) == "table" and w or { w, w }
h = type(h) == "table" and h or { h, h }
assert(w[1] >= 1 and w[2] >= 1)
assert(w[1] <= w[2])
assert(h[1] >= 1 and h[2] >= 1)
assert(h[1] <= h[2])
assert(type(cb_func) == "string" or type(cb_func) == "function")
data = data or {}
-- Append
self.containers[#self.containers + 1] = {
pos_x = x, pos_y = y, -- Desired position
lim_x = w, lim_y = h, -- Width/height limits
callback = cb_func,
data = data,
hidden = true -- Yet no intersections
}
end
function ft:_render_preprocess()
for i, c in ipairs(self.containers) do
-- Start with minimal size
c.dim_x = c.lim_x[1]
c.dim_y = c.lim_y[1]
-- Keep in bounds
c.pos_x = math.min(c.pos_x, self.width - c.dim_x)
c.pos_y = math.min(c.pos_y, self.width - c.dim_y)
c.pos_x = math.max(c.pos_x, 0)
c.pos_y = math.max(c.pos_y, 0)
end
-- Start from top left
local function get_distance_sq(c)
local x = c.pos_x + c.dim_x / 2
local y = c.pos_y + c.dim_y / 2
return (x * x + y * y) - c.dim_x * c.dim_y
end
table.sort(self.containers, function(a, b)
return get_distance_sq(a) < get_distance_sq(b)
end)
end
local function logme(what, c)
print(what .. "\t " .. c.data[1] .. ": " .. c.pos_x .. ", " .. c.pos_y ..
"; " .. c.dim_x .. ", " .. c.dim_y)
end
function ft:_render_make_formspec()
-- Container for formspec elements
local fs = {}
for _, c in ipairs(self.containers) do
local start_i = #fs + 1
fs[start_i] = ("container[%.1f,%.1f]"):format(c.pos_x, c.pos_y)
local fits = true
logme("plot", c)
if type(c.callback) == "function" then
fits = c.callback(c.dim_x, c.dim_y, fs, c.data)
else
-- String for fixed-size containers
fs[#fs + 1] = c.callback
end
if c.hidden then
-- For debugging
fs[#fs + 1] = "label[0,0;H]"
end
if fits then
fs[#fs + 1] = "container_end[]"
else
local scrollbar_name = "scrollbar_TODO"
fs[start_i] = ("scroll_container[%f,%f;%f,%f;%s;vertical]"):format(
c.pos_x, c.pos_y, c.dim_x, c.dim_y, scrollbar_name)
fs[#fs + 1] = "scroll_container_end[]"
fs[#fs + 1] = ("scrollbar[%f,%f;%f,%f;vertical;%s;]"):format(
c.pos_x + c.dim_x, c.pos_y, 0.1, c.dim_y, scrollbar_name)
end
end
return table.concat(fs, '\n')
end
-- Intersection box calculation
function ft:_get_intersection(a, b)
if a == b or a.hidden or b.hidden then
return
end
if a.pos_x < b.pos_x + b.dim_x and
a.pos_y < b.pos_y + b.dim_y and
a.pos_x + a.dim_x > b.pos_x and
a.pos_y + a.dim_y > b.pos_y then
-- Intersection!
return { -- X-Coordinates (min, max)
math.max(a.pos_x, b.pos_x),
math.min(a.pos_x + a.dim_x, b.pos_x + b.dim_x)
}, { -- Y-Coordinates (min, max)
math.max(a.pos_y, b.pos_y),
math.min(a.pos_y + a.dim_y, b.pos_y + b.dim_y)
}
end
end
function ft:_get_intersection_info(c)
local x, y = 0, 0
if c.pos_x < 0 then x = -1 end
if c.pos_y < 0 then y = -1 end
if c.pos_x + c.dim_x > self.width then x = self.width + 1 end
if c.pos_y + c.dim_y > self.height then y = self.height + 1 end
if x ~= 0 or y ~= 0 then
-- Outer boundary collision, use some high value
logme("outer collision", c)
return x, y, 1000
end
local x, y, area = 0, 0, 0
local cbox_x, cbox_y = {self.width, 0}, {self.height, 0}
for _, c2 in ipairs(self.containers) do
local ix, iy = self:_get_intersection(c, c2)
if ix then
local i_area = (ix[2] - ix[1]) * (iy[2] - iy[1])
x = x + (ix[1] + ix[2]) / 2 * i_area
y = y + (iy[1] + iy[2]) / 2 * i_area
-- Sum up the total collision box area
area = area + i_area
-- Biggest bounding collision box
cbox_x[1] = math.min(cbox_x[1], ix[1])
cbox_x[2] = math.max(cbox_x[2], ix[2])
cbox_y[1] = math.min(cbox_y[1], iy[1])
cbox_y[2] = math.max(cbox_y[2], iy[2])
end
end
if area == 0 then
return
end
-- mass center (X, Y), area and maximal collision box bounds
return x / area, y / area, area, cbox_x, cbox_y
end
-- Mass center of all visible (hidden = false) areas
function ft:_get_free_area(c_to_ignore)
local area, x, y = 0, 0, 0
for _, c in ipairs(self.containers) do
if not c.hidden and c ~= c_to_ignore then
local c_area = c.dim_x * c.dim_y
x = x + (c.pos_x + c.dim_x / 2) * c_area
y = y + (c.pos_y + c.dim_y / 2) * c_area
area = area + c_area
end
end
-- Default to bottom right
if area == 0 then area = 1 end
return self.width - x / area, self.height - y / area, area
end
function ft:render(iterations)
iterations = iterations or 2
self:_render_preprocess()
for i = 1, iterations do
local moved = false
print(" ==> Iteration " .. i)
for _, c in ipairs(self.containers) do
-- Place, then move
c.hidden = false
local ix, iy, i_area, cbox_x, cbox_y = self:_get_intersection_info(c)
if ix then
local sx, sy, s_area = self:_get_free_area(c)
print(("Free area: %.2f, %.2f"):format(sx, sy))
-- Get movement direction
local dx = sx - 2 * ix + (c.pos_x + c.dim_x / 2) --(sx + ix) / (s_area + i_area)
local dy = sy - 2 * iy + (c.pos_y + c.dim_y / 2) --(sy + iy) / (s_area + i_area)
local old_x, old_y = c.pos_x, c.pos_y
local cx = cbox_x[2] - cbox_x[1]
local cy = cbox_y[2] - cbox_y[1]
if cy > cx then
-- Move to free area in X
c.pos_x = c.pos_x + math.sign(dx) * cx
logme(" moveX " .. dx .. ";" .. cx, c)
else
-- Move to free area in Y
c.pos_y = c.pos_y + math.sign(dy) * cy
logme(" moveY " .. dy .. ";" .. cy, c)
end
local _, _, i_area2 = self:_get_intersection_info(c)
if (i_area2 or 0) > i_area then
c.pos_x, c.pos_y = old_x, old_y
else
moved = true
end
end
end
if not moved then
break
end
end
-- Enlarge if possible
for _, c in ipairs(self.containers) do
if not c.hidden and c.dim_x < c.lim_x[2] then
-- Maximize X direction
c.dim_x = c.lim_x[2]
local _, _, _, cbox_x, cbox_y = self:_get_intersection_info(c)
if cbox_x then
logme("max X fail " .. (cbox_x[2] - cbox_x[1]) .. "x" .. (cbox_y[2] - cbox_y[1]), c)
c.dim_x = math.max(c.lim_x[1], cbox_x[1] - c.pos_x)
end
end
if not c.hidden and c.dim_y < c.lim_y[2] then
-- Maximize Y direction
c.dim_y = c.lim_y[2]
local _, _, _, cbox_x, cbox_y = self:_get_intersection_info(c)
if cbox_y then
logme("max Y fail " .. (cbox_x[2] - cbox_x[1]) .. "x" .. (cbox_y[2] - cbox_y[1]), c)
c.dim_y = math.max(c.lim_y[1], cbox_y[1] - c.pos_y)
end
end
end
return self:_render_make_formspec()
end
local function demo(iter)
local colors = { "#F00", "#0FF", "#FAA","#0F0" }
local function mk_box(w, h, fs, data)
fs[#fs + 1] = "box[0.1,0.1;" .. w.. "," .. h..";" .. colors[data[1]] .."]"
fs[#fs + 1] = "label[0.1,0.4;Box " .. data[1] .."]"
return true
end
local tt = FSTile(12, 9)
tt:add_container(0, 1, 5, {4, 8}, mk_box, { 1 })
tt:add_container(3, 0, {3, 7}, 5, mk_box, { 2 })
tt:add_container(0, 3, {8, 20}, 1, mk_box, { 3 })
tt:add_container(4, 4, {3, 4}, {2, 3}, mk_box, { 4 })
local fs = {
"formspec_version[4]",
"size[12,9]",
tt:render(iter)
}
return fs
end
--print(table.concat(demo(10), '\n'))
minetest.register_chatcommand("a", {
func = function(name, param)
local fs = demo(tonumber(param))
minetest.show_formspec(name, "baz", table.concat(fs, '\n'))
end
})
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