main.lua

   1 print "lua is up and running"
   2 print(draw.framefunc)
   3
   4 particle = {list = {}}
   5 function particle:spawn (x,y,vx,vy,maxage)
   6         local p = {x=x,y=y,vx=vx,vy=vy,age=0,maxage = maxage or 10}
   7         self.list[#self.list+1] = p
   8         return p
   9 end
  10
  11 function particle:step()
  12         for i=#self.list,1,-1 do
  13                 local p = self.list[i]
  14                 p.x = p.x + p.vx
  15                 p.y = p.y + p.vy
  16                 p.age = p.age + 1
  17                 if p.think then p:think() end
  18                 if p.age > p.maxage then
  19                         table.remove(self.list,i)
  20                 end
  21         end
  22 end
  23
  24 function particle:draw()
  25         local rect = draw.rect
  26         for i=#self.list,1,-1 do
  27                 local p = self.list[i]
  28                 if p.draw then p:draw() else
  29                         rect(p.x-2,p.y-2,4,4,1,1,1,1)
  30                 end
  31         end
  32 end
  33
  34 function engine.frame ()
  35         draw.rect(0,0,3,3,1,1,1,1)
  36         draw.rect(5,0,1,5,1,0,0,1)
  37         draw.rect(0,5,5,1,0,1,1,1)
  38
  39         if math.random()>.9 then
  40                 local p = particle:spawn(200,200,(math.random()-.5),(math.random()-.5),math.random(300,1000))
  41                 function p:think()
  42                         p.vx,p.vy = p.vx*.99,p.vy*.99-.002
  43                 end
  44                 function p:draw()
  45                         local x,y = self.x,self.y
  46                         local m,a = self.maxage,self.age
  47                         local p = 1-a/m
  48                         local s = (1-p)*30+30
  49                         draw.rect(x-s,y-s,s*2,s*2,1,1,1,p)
  50                 end
  51         end
  52         io.write("\r",#particle.list)
  53         particle:step()
  54         particle:draw()
  55 --      draw.framefunc()
  56 --      draw.rect(0,0,10,10,1,1,0,1)
  57 end