Just a few questions inline:
On 11/07/2023 21:52, Michael Strauß wrote:
Easing Functions
----------------
CSS Transitions specifies the `transition-timing-function`
sub-property to define easing functions (see CSS Easing Functions
[4]). Here is a list of all easing functions available in CSS Easing
Functions:
* linear
* ease, ease-in, ease-out, ease-in-out, cubic-bezier(x1, y1, x2, y2)
* step-start, step-end, steps(intervals, step-position)
Easing functions are implemented using `javafx.animation.Interpolator`
in JavaFX. While it may seem straightforward to re-use existing
interpolator implementations like `Interpolator.EASE_IN`,
`Interpolator.EASE_OUT`, etc., the definitions of those interpolators
don't match the definitions of CSS Easing Functions. In order to
maximize compatibility with CSS Transitions, implicit transitions use
the CSS definitions, not the SMIL 3.0 definitions of the existing
interpolator implementations.
Should this also provide fx-ease-in (etc) if you want to be compatible
with other FX animations instead of CSS ones (which have little meaning
in FX apps) ?
Note that step-wise interpolators are only available for CSS
Transitions, they are not exposed as new public API in the
`javafx.animation` framework. The reason for this is that step-wise
interpolators accept negative input values and can produce different
results depending on their `step-position` parameter (for details on
that, see "2.3.1. Output of a step easing function" [5]).
I would think that an Interpolator still has a defined begin and end
state, regardless if it is step based or a smooth transition. Perhaps
I'm misunderstanding something here about the step based transitions,
but I don't see why the fraction value running from 0 to 1 would be
incompatible with step based transitions. The following interpolator
would create 10 discrete steps:
new Interpolator() {
@Override
protected double curve(double t) {
return Math.floor(t * 10) / 10; // 10 steps
}
};
Add some parameters, and make adjustments for the various CSS jump
types, whether ceil/floor should be used, etc, and I think it could
implement the CSS step variants as well.
--John
