backIn backInOut backOut bounceIn bounceInOut bounceOut byName circularIn circularInOut circularOut cubicIn cubicInOut cubicOut def elasticIn elasticInOut elasticOut exponentialIn exponentialInOut exponentialOut linear quadraticIn quadraticInOut quadraticOut quarticIn quarticInOut quarticOut quinticIn quinticInOut quinticOut sinusoidalIn sinusoidalInOut sinusoidalOut stepped

quinticInOut detail::quinticInOutEasing quinticInOut {} inlineconstexpr Quintic polynomial easing with very strong acceleration and deceleration. The quinticInOut easing function provides the strongest polynomial S-curve, creating powerful motion with maximum polynomial emphasis. Motion profile: First half: Very strong acceleration (t⁵) Midpoint: Maximum velocity Second half: Very strong deceleration Creates dramatic S-curve This easing is appropriate for: Applications prioritizing strong visual emphasis: Galleries, portfolios, marketing sites Animations requiring maximum polynomial emphasis: At both acceleration and deceleration phases Important transitions: Focal, memorable moments Longer animations: 500ms+ durations Mathematically: Combines quinticIn for t < 0.5 and quinticOut for t >= 0.5 // Premium screen transition auto x = tweeny::from(0.0f) .to(1920.0f) .via(easing::quinticInOut) .during(50U) .build(); See also quinticIn For only very strong acceleration quinticOut For only very strong deceleration quarticInOut For gentler motion exponentialInOut For more extreme motion Visualize at https://easings.net/#easeInOutQuint