Docs: easing

You can use a different easing just passing some ease_* script to the "ease" VAR when you are creating your tween. For example, to use the ease_bouncein ease in your tween:

tween_to(id, 1, array("x", x + 200, "ease", ease_bouncein));

Tweenline currently supports 35 different easing types.

ease_quadin ease_quadout ease_quadinout
ease_cubicin ease_cubicout ease_cubicinout
ease_quartin ease_quartout ease_quartinout
ease_quintin ease_quintout ease_quintinou
ease_sinein ease_sineout ease_sineinout
ease_expoin ease_expoout ease_expoinout
ease_circin ease_circout ease_circinout
ease_bouncein ease_bounceout ease_bounceinout
ease_backin ease_backout ease_backinout
ease_powin ease_powout ease_powinout
ease_elasticin ease_elasticout ease_elasticinout

Easing modifiers

You can use modifiers on some eases to change their behaviour. For example, you can change the overshot on the ease_back to to create a more dramatic effect. All the modifiers are real values. If you pass a non real argument, the default value is used instaed.

ease_back (in/out/inout) modifiers

tween_set_modifiers(tween_index, [overshot]);

overshot: [default = 1.70158]

Overshoot affects the degree or strength of the overshoot.

ease_pow (in/out/inout) modifiers

tween_set_modifiers(tween_index, [power]);

power: [default = 6]

Adjust which power() function will be used to calculate the tween. As big is the power modifier, more pronunced will be the easing. Try to use a small number, as this function has a big CPU overhead. If you want to use a number below 6, please use: (they are super optimized)

ease_slowmotion modifiers

tween_set_modifiers(tween_index, [linearRatio, power, yoyoMode]);

linearRatio: [default = 0.7]

The proportion of the ease during which the rate of change will be linear (steady pace). This should be a number between 0 and 1. For example, 0.5 would be half, so the first 25% of the ease would be easing out (decelerating), then 50% would be linear, then the final 25% would be easing in (accelerating). If you choose 0.8, that would mean 80% of the ease would be linear, leaving 10% on each end to ease.

power: [default = 0.7]

The strength of the ease at each end. If you define a value above 1, it will actually reverse the linear portion in the middle which can create interesting effects.

yoyoMode [default = false]

If true, the ease will reach its destination value mid-tween and maintain it during the entire linear mode and then go back to the original value at the end (like a yoyo of sorts). This can be very useful if, for example, you want the alpha (or some other property) of some text to fade at the front end of a SlowMo positional ease and then back down again at the end of that positional SlowMo tween. Otherwise you would need to create separate tweens for the beginning and ending fades that match up with that positional tween.