replace the frame count unit from the int32_t to float
since animations could smoothly interpolate key-frames.
This notificably improve the animation smoothness in Lottie
Beta API changes:
Result Animation::frame(uint32_t no) -> Result Animation::frame(float no)
uint32_t Animation::curFrame() const -> float Animation::curFrame() const
uint32_t Animation::totalFrame() const -> float Animation::totalFrame() const
Lottie ColorStop RGB / Alpha can be dealt with individually.
Since thorvg handles this one unified set,
lottie model need to merge the data into one structure.
Replace the linear search algorithm with binary-search.
The performance enhancement may not yield significant benefits in normal cases.
However, it becomes crucial if the animation comprises an extensive number of frames...
