Tweening is an animation term, which has been adapted by programmers. It's basic meaning is taking 2 images, and then filling in the timeframe inbetween to make the progression animated.
Here's another tween example for you, that you can copy, paste and run. It's very similar to Spectrepaul's, but with the addition of chains. Although they are fairly primitive, they may be enough for simple GUIs, to add a little animation.
// Project: Tween
// Created: 2015-02-05
// set window properties
SetWindowTitle( "TweenShuttle" )
SetWindowSize( 1024, 768, 0 )
// set display properties
SetVirtualResolution( 1024, 768 )
txt = createText("Drop & Pop")
setTextSize(txt, 40 )
settextAlignment(txt,1)
setTextPosition(txt, getVirtualWidth() /2,100)
//A chain allows you to create a sequenece of tweens
chain = createTweenChain()
//We need a Drop & Pop tween
Drop = CreateTweenText(2)
Pop = CreateTweenText(0.5)
FloatBack = CreateTweenText(5)
Shrink = CreateTweenText(1)
//set the actions of our new tweens
SetTweenTextY(Drop,100, 650,7)
SetTweenTextSize(Pop, 40,50,8)
SetTweenTextY(FloatBack,650, 100,2)
SetTweenTextSize(Shrink, 50,40,2)
//Add the tweens to the chain in pairs, 10 times over
for n = 1 to 10
AddTweenChainText(chain,Drop,txt,2)
AddTweenChainText(chain,Pop,txt,1)
AddTweenChainText(chain,FloatBack,txt,1)
AddTweenChainText(chain,Shrink,txt,1)
next n
//Start the tween chain
PlayTweenChain(chain)
do
//just call UpdateAllTweens() and the sprite will take care of itself!
UpdateAllTweens(GetFrameTime())
Print( ScreenFPS() )
Sync()
loop
end
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