Files
dusk/src/dusk/animation/easing.c
T
2026-05-08 15:44:55 -05:00

112 lines
2.4 KiB
C

// Copyright (c) 2026 Dominic Masters
//
// This software is released under the MIT License.
// https://opensource.org/licenses/MIT
#include "easing.h"
#include "assert/assert.h"
#include <math.h>
const easingfn_t EASING_FUNCTIONS[EASING_COUNT] = {
easingLinear,
easingInSine,
easingOutSine,
easingInOutSine,
easingInQuad,
easingOutQuad,
easingInOutQuad,
easingInCubic,
easingOutCubic,
easingInOutCubic,
easingInQuart,
easingOutQuart,
easingInOutQuart,
easingInBack,
easingOutBack,
easingInOutBack,
};
float_t easingApply(const easingtype_t type, const float_t t) {
assertTrue(type < EASING_COUNT, "Invalid easing type");
return EASING_FUNCTIONS[type](t);
}
float_t easingLinear(const float_t t) {
return t;
}
float_t easingInSine(const float_t t) {
return 1.0f - cosf(t * EASING_PI * 0.5f);
}
float_t easingOutSine(const float_t t) {
return sinf(t * EASING_PI * 0.5f);
}
float_t easingInOutSine(const float_t t) {
return -(cosf(EASING_PI * t) - 1.0f) * 0.5f;
}
float_t easingInQuad(const float_t t) {
return t * t;
}
float_t easingOutQuad(const float_t t) {
float_t u = 1.0f - t;
return 1.0f - u * u;
}
float_t easingInOutQuad(const float_t t) {
if(t < 0.5f) return 2.0f * t * t;
float_t u = -2.0f * t + 2.0f;
return 1.0f - u * u * 0.5f;
}
float_t easingInCubic(const float_t t) {
return t * t * t;
}
float_t easingOutCubic(const float_t t) {
float_t u = 1.0f - t;
return 1.0f - u * u * u;
}
float_t easingInOutCubic(const float_t t) {
if(t < 0.5f) return 4.0f * t * t * t;
float_t u = -2.0f * t + 2.0f;
return 1.0f - u * u * u * 0.5f;
}
float_t easingInQuart(const float_t t) {
return t * t * t * t;
}
float_t easingOutQuart(const float_t t) {
float_t u = 1.0f - t;
return 1.0f - u * u * u * u;
}
float_t easingInOutQuart(const float_t t) {
if(t < 0.5f) return 8.0f * t * t * t * t;
float_t u = -2.0f * t + 2.0f;
return 1.0f - u * u * u * u * 0.5f;
}
float_t easingInBack(const float_t t) {
return EASING_C3 * t * t * t - EASING_C1 * t * t;
}
float_t easingOutBack(const float_t t) {
float_t u = t - 1.0f;
return 1.0f + EASING_C3 * u * u * u + EASING_C1 * u * u;
}
float_t easingInOutBack(const float_t t) {
if(t < 0.5f) {
float_t u = 2.0f * t;
return u * u * ((EASING_C2 + 1.0f) * u - EASING_C2) * 0.5f;
}
float_t u = 2.0f * t - 2.0f;
return (u * u * ((EASING_C2 + 1.0f) * u + EASING_C2) + 2.0f) * 0.5f;
}