Difference between revisions of "dt"

(Created page with "dt is the most common shorthand for deltatime, which is passed through love.update to let the function know how much time has passed since it was last run.")
 
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dt is the most common shorthand for deltatime, which is passed through [[love.update]] to let the function know how much time has passed since it was last run.
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dt is the most common shorthand for delta-time, which is usually passed through [[love.update]] to represent the amount of time which has passed since it was last called. It is in seconds, but because of the speed of modern processors is usually smaller than 1 values like 0.01 are common.
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== Examples ==
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=== Increase a variable x by 1 every second ===
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<source lang="lua">
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x = 0
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function love.update(dt)
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  x = x + dt
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end
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</source>
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=== Change a position x at a fixed speed while a key is held down ===
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<source lang="lua">
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x = 0
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speed = 32
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function love.update(dt)
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  if love.keyboard.isDown("right") then
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      x = x + (speed * dt)  -- x will increase by 32 for every second right is held down
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  elseif love.keyboard.isDown("left") then
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      x = x - (speed * dt)
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  end
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end
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</source>
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== See Also ==
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* [[love.update]]
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* [[love.timer.getDelta]]
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== Other Languages ==
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{{i18n|dt}}

Latest revision as of 03:05, 29 May 2017

dt is the most common shorthand for delta-time, which is usually passed through love.update to represent the amount of time which has passed since it was last called. It is in seconds, but because of the speed of modern processors is usually smaller than 1 values like 0.01 are common.

Examples

Increase a variable x by 1 every second

x = 0
function love.update(dt)
   x = x + dt
end


Change a position x at a fixed speed while a key is held down

x = 0
speed = 32
function love.update(dt)
   if love.keyboard.isDown("right") then
      x = x + (speed * dt)  -- x will increase by 32 for every second right is held down
   elseif love.keyboard.isDown("left") then
      x = x - (speed * dt)
   end
end

See Also


Other Languages