1 a0b1acd8 2022-12-18 op --
  2 a0b1acd8 2022-12-18 op -- tick
  3 a0b1acd8 2022-12-18 op --
  4 a0b1acd8 2022-12-18 op -- Copyright (c) 2015 rxi
  5 a0b1acd8 2022-12-18 op --
  6 a0b1acd8 2022-12-18 op -- This library is free software; you can redistribute it and/or modify it
  7 a0b1acd8 2022-12-18 op -- under the terms of the MIT license. See LICENSE for details.
  8 a0b1acd8 2022-12-18 op --
  9 a0b1acd8 2022-12-18 op 
 10 a0b1acd8 2022-12-18 op local tick = { _version = "0.1.1" }
 11 a0b1acd8 2022-12-18 op tick.__index = tick
 12 a0b1acd8 2022-12-18 op 
 13 a0b1acd8 2022-12-18 op 
 14 a0b1acd8 2022-12-18 op local iscallable = function(x)
 15 a0b1acd8 2022-12-18 op   if type(x) == "function" then return true end
 16 a0b1acd8 2022-12-18 op   local mt = getmetatable(x)
 17 a0b1acd8 2022-12-18 op   return mt and mt.__call ~= nil
 18 a0b1acd8 2022-12-18 op end
 19 a0b1acd8 2022-12-18 op 
 20 a0b1acd8 2022-12-18 op local noop = function()
 21 a0b1acd8 2022-12-18 op end
 22 a0b1acd8 2022-12-18 op 
 23 a0b1acd8 2022-12-18 op 
 24 a0b1acd8 2022-12-18 op local event = {}
 25 a0b1acd8 2022-12-18 op event.__index = event
 26 a0b1acd8 2022-12-18 op 
 27 a0b1acd8 2022-12-18 op function event.new(parent, fn, delay, recur, err)
 28 a0b1acd8 2022-12-18 op   err = err or 0
 29 a0b1acd8 2022-12-18 op   -- Create and return event
 30 a0b1acd8 2022-12-18 op   return setmetatable({
 31 a0b1acd8 2022-12-18 op     parent  = parent,
 32 a0b1acd8 2022-12-18 op     delay   = delay,
 33 a0b1acd8 2022-12-18 op     timer   = delay + err,
 34 a0b1acd8 2022-12-18 op     fn      = fn,
 35 a0b1acd8 2022-12-18 op     recur   = recur,
 36 a0b1acd8 2022-12-18 op   }, event)
 37 a0b1acd8 2022-12-18 op end
 38 a0b1acd8 2022-12-18 op 
 39 a0b1acd8 2022-12-18 op 
 40 a0b1acd8 2022-12-18 op function event:after(fn, delay)
 41 a0b1acd8 2022-12-18 op   -- Error check
 42 a0b1acd8 2022-12-18 op   if self.recur then
 43 a0b1acd8 2022-12-18 op     error("cannot chain a recurring event")
 44 a0b1acd8 2022-12-18 op   end
 45 a0b1acd8 2022-12-18 op   -- Chain event
 46 a0b1acd8 2022-12-18 op   local oldfn = self.fn
 47 a0b1acd8 2022-12-18 op   local e = event.new(self.parent, fn, delay, false)
 48 a0b1acd8 2022-12-18 op   self.fn = function()
 49 a0b1acd8 2022-12-18 op     oldfn()
 50 a0b1acd8 2022-12-18 op     e.timer = e.timer + self.parent.err
 51 a0b1acd8 2022-12-18 op     self.parent:add(e)
 52 a0b1acd8 2022-12-18 op   end
 53 a0b1acd8 2022-12-18 op   return e
 54 a0b1acd8 2022-12-18 op end
 55 a0b1acd8 2022-12-18 op 
 56 a0b1acd8 2022-12-18 op 
 57 a0b1acd8 2022-12-18 op function event:stop()
 58 a0b1acd8 2022-12-18 op   tick.remove(self.parent, self)
 59 a0b1acd8 2022-12-18 op end
 60 a0b1acd8 2022-12-18 op 
 61 a0b1acd8 2022-12-18 op 
 62 a0b1acd8 2022-12-18 op 
 63 a0b1acd8 2022-12-18 op function tick.group()
 64 a0b1acd8 2022-12-18 op   return setmetatable({ err = 0 }, tick)
 65 a0b1acd8 2022-12-18 op end
 66 a0b1acd8 2022-12-18 op 
 67 a0b1acd8 2022-12-18 op 
 68 a0b1acd8 2022-12-18 op function tick:add(e)
 69 a0b1acd8 2022-12-18 op   self[e] = true
 70 a0b1acd8 2022-12-18 op   table.insert(self, e)
 71 a0b1acd8 2022-12-18 op   return e
 72 a0b1acd8 2022-12-18 op end
 73 a0b1acd8 2022-12-18 op 
 74 a0b1acd8 2022-12-18 op 
 75 a0b1acd8 2022-12-18 op function tick:remove(e)
 76 a0b1acd8 2022-12-18 op   if type(e) == "number" then
 77 a0b1acd8 2022-12-18 op     -- Remove and return event
 78 a0b1acd8 2022-12-18 op     local idx = e
 79 a0b1acd8 2022-12-18 op     e = self[idx]
 80 a0b1acd8 2022-12-18 op     self[e] = nil
 81 a0b1acd8 2022-12-18 op     self[idx] = self[#self]
 82 a0b1acd8 2022-12-18 op     table.remove(self)
 83 a0b1acd8 2022-12-18 op     return e
 84 a0b1acd8 2022-12-18 op   end
 85 a0b1acd8 2022-12-18 op   self[e] = false
 86 a0b1acd8 2022-12-18 op   for i, v in ipairs(self) do
 87 a0b1acd8 2022-12-18 op     if v == e then
 88 a0b1acd8 2022-12-18 op       return self:remove(i)
 89 a0b1acd8 2022-12-18 op     end
 90 a0b1acd8 2022-12-18 op   end
 91 a0b1acd8 2022-12-18 op end
 92 a0b1acd8 2022-12-18 op 
 93 a0b1acd8 2022-12-18 op 
 94 a0b1acd8 2022-12-18 op function tick:update(dt)
 95 a0b1acd8 2022-12-18 op   for i = #self, 1, -1 do
 96 a0b1acd8 2022-12-18 op     local e = self[i]
 97 a0b1acd8 2022-12-18 op     e.timer = e.timer - dt
 98 a0b1acd8 2022-12-18 op     while e.timer <= 0 do
 99 a0b1acd8 2022-12-18 op       if e.recur then
100 a0b1acd8 2022-12-18 op         e.timer = e.timer + e.delay
101 a0b1acd8 2022-12-18 op       else
102 a0b1acd8 2022-12-18 op         self:remove(i) 
103 a0b1acd8 2022-12-18 op       end
104 a0b1acd8 2022-12-18 op       self.err = e.timer
105 a0b1acd8 2022-12-18 op       e.fn()
106 a0b1acd8 2022-12-18 op       if not e.recur then
107 a0b1acd8 2022-12-18 op         break
108 a0b1acd8 2022-12-18 op       end
109 a0b1acd8 2022-12-18 op     end
110 a0b1acd8 2022-12-18 op   end
111 a0b1acd8 2022-12-18 op   self.err = 0
112 a0b1acd8 2022-12-18 op end
113 a0b1acd8 2022-12-18 op 
114 a0b1acd8 2022-12-18 op 
115 a0b1acd8 2022-12-18 op function tick:event(fn, delay, recur)
116 a0b1acd8 2022-12-18 op   delay = tonumber(delay)
117 a0b1acd8 2022-12-18 op   -- Error check
118 a0b1acd8 2022-12-18 op   if not iscallable(fn) then
119 a0b1acd8 2022-12-18 op     error("expected `fn` to be callable")
120 a0b1acd8 2022-12-18 op   end
121 a0b1acd8 2022-12-18 op   if type(delay) ~= "number" then
122 a0b1acd8 2022-12-18 op     error("expected `delay` to be a number")
123 a0b1acd8 2022-12-18 op   end
124 a0b1acd8 2022-12-18 op   if delay < 0 then
125 a0b1acd8 2022-12-18 op     error("expected `delay` of zero or greater")
126 a0b1acd8 2022-12-18 op   end
127 a0b1acd8 2022-12-18 op   -- If, factoring in the timing error, the event should happen *now* the
128 a0b1acd8 2022-12-18 op   -- function is immediately called and the error is temporarily carried
129 a0b1acd8 2022-12-18 op   -- through. This assures nested events with delays shorter than the update()
130 a0b1acd8 2022-12-18 op   -- delta-time do not accumulate error; several nested events with very small
131 a0b1acd8 2022-12-18 op   -- delays may end up being called on the same frame. A dummy event is created
132 a0b1acd8 2022-12-18 op   -- and returned so :after() still functions correctly.
133 a0b1acd8 2022-12-18 op   local d = delay + self.err
134 a0b1acd8 2022-12-18 op   if d < 0 then
135 a0b1acd8 2022-12-18 op     local err = self.err
136 a0b1acd8 2022-12-18 op     self.err = d
137 a0b1acd8 2022-12-18 op     fn()
138 a0b1acd8 2022-12-18 op     self.err = err
139 a0b1acd8 2022-12-18 op     return self:add(event.new(self, noop, delay, recur, self.err))
140 a0b1acd8 2022-12-18 op   end
141 a0b1acd8 2022-12-18 op   -- Create, add and return a normal event
142 a0b1acd8 2022-12-18 op   return self:add(event.new(self, fn, delay, recur, self.err))
143 a0b1acd8 2022-12-18 op end
144 a0b1acd8 2022-12-18 op 
145 a0b1acd8 2022-12-18 op 
146 a0b1acd8 2022-12-18 op function tick:delay(fn, delay)
147 a0b1acd8 2022-12-18 op   return self:event(fn, delay, false)
148 a0b1acd8 2022-12-18 op end
149 a0b1acd8 2022-12-18 op 
150 a0b1acd8 2022-12-18 op 
151 a0b1acd8 2022-12-18 op function tick:recur(fn, delay)
152 a0b1acd8 2022-12-18 op   return self:event(fn, delay, true)
153 a0b1acd8 2022-12-18 op end
154 a0b1acd8 2022-12-18 op 
155 a0b1acd8 2022-12-18 op 
156 a0b1acd8 2022-12-18 op local group = tick.group()
157 a0b1acd8 2022-12-18 op 
158 a0b1acd8 2022-12-18 op local bound = {
159 a0b1acd8 2022-12-18 op   update  = function(...) return tick.update(group, ...) end,
160 a0b1acd8 2022-12-18 op   delay   = function(...) return tick.delay (group, ...) end,
161 a0b1acd8 2022-12-18 op   recur   = function(...) return tick.recur (group, ...) end,
162 a0b1acd8 2022-12-18 op   remove  = function(...) return tick.remove(group, ...) end,
163 a0b1acd8 2022-12-18 op }
164 a0b1acd8 2022-12-18 op setmetatable(bound, tick)
165 a0b1acd8 2022-12-18 op 
166 a0b1acd8 2022-12-18 op return bound