On Fri, 6 Jun 2025 23:23:05 GMT, Michael Strauß <mstra...@openjdk.org> wrote:
> JavaFX unnecessarily restricts interpolation in the following ways: > 1. `Interpolatable` implementations often clamp intermediate values to the > interpolation factor range [0,1]. > 2. `SplineInterpolator` doesn't accept Y coordinates outside of [0,1] for its > control points. While this was probably done so that the computed > interpolation factor doesn't exceed [0,1], the restriction goes far beyond > that. For example, the following function is not representable, even though > its values are all within the [0,1] range:<br> > <img > src="https://github.com/user-attachments/assets/368b6142-052d-4ead-8a59-cbddf4a19660"; > width="400"/><br> > The following function is also not representable, but would be very useful > for [bouncy animations](https://easings.net/#easeOutBack):<br> > <img > src="https://github.com/user-attachments/assets/af02b044-ae4c-4250-b181-72178ad9f3f3"; > width="400"/> > > Fortunately, there is no technical reason why JavaFX can't support the full > range of animations that can be represented with a cubic Beziér interpolation > function. > > This PR includes the following changes: > 1. The specification of `Interpolatable` is changed to require > implementations to accept interpolation factors outside of [0,1]. > 2. All implementations of `Interpolatable` now correctly return intermediate > values outside of [0,1]. > 3. `SplineInterpolator` now accepts control points with any Y coordinate. > > Here's how the result looks like for the previously unrepresentable > interpolation function `cubic-bezier(0.34, 2.2, 0.64, 1)`:<br> > <img > src="https://github.com/user-attachments/assets/72c10d0d-71b4-4bb5-b58c-ae377279b0fd"; > width="500"/> This pull request has now been integrated. Changeset: 999c396d Author: Michael Strauß <mstra...@openjdk.org> URL: https://git.openjdk.org/jfx/commit/999c396d3c8d76be5b25c08e66490f026ae7b99a Stats: 784 lines in 52 files changed: 533 ins; 33 del; 218 mod 8358820: Allow interpolation outside of range [0,1] Reviewed-by: angorya, kcr ------------- PR: https://git.openjdk.org/jfx/pull/1822
