[skottie] Improved Hue/Saturation effect
The current HueSaturation effect implementation relies on a simple
HSLA color matrix operation and assumes the controls are linear.
Turns out AE's saturation is more sophisticated, both in implementation
and in control mapping.
Updating the effect to use a chain of specialized color filters:
- keep HSLAMatrix() for hue adjustments
- introduce a custom runtime effect for saturation
(following AE's semantics)
- use a plain Matrix() CF for lightness adjustments
Change-Id: Iba6c9f7fd8c01dc33c1cd00822ea546867c057ac
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/452976
Commit-Queue: Florin Malita <fmalita@chromium.org>
Commit-Queue: Florin Malita <fmalita@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
2 files changed