Difference between revisions of "love.update"

(add another example)
Line 19: Line 19:
 
     npc.think()
 
     npc.think()
 
   end
 
   end
 +
end
 +
</source>
 +
Change a variable at a constant rate (3 per second).
 +
<source lang="lua">
 +
var = 10
 +
rate = 3 -- change to change the rate at which the var is changed
 +
function love.update(dt)
 +
  if love.keyboard.isDown("down") then
 +
      var = var + (dt * rate)
 +
  elseif love.keyboard.isDown("up") then
 +
      var = var - (dt * rate)
 +
  end
 
end
 
end
 
</source>
 
</source>

Revision as of 05:05, 26 September 2011

Callback function used to update the state of the game every frame.

Function

Synopsis

love.update( dt )

Arguments

number dt
Time since the last update in seconds.

Returns

Nothing.

Examples

Run a function called think inside a table called npc approximately once per second.

dtotal = 0
function love.update(dt)
  dtotal = dtotal + dt
  if dtotal > 1 then
    dtotal = dtotal - 1
    npc.think()
  end
end

Change a variable at a constant rate (3 per second).

var = 10
rate = 3 -- change to change the rate at which the var is changed
function love.update(dt)
   if love.keyboard.isDown("down") then
      var = var + (dt * rate)
   elseif love.keyboard.isDown("up") then
      var = var - (dt * rate)
   end
end

See Also


Other Languages