godot/scene/animation/easing_equations.h
2021-09-24 13:47:13 +02:00

406 lines
10 KiB
C++

/*************************************************************************/
/* easing_equations.h */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
/*
* Derived from Robert Penner's easing equations: http://robertpenner.com/easing/
*
* Copyright (c) 2001 Robert Penner
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#ifndef EASING_EQUATIONS_H
#define EASING_EQUATIONS_H
namespace linear {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return c * t / d + b;
}
}; // namespace linear
namespace sine {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return -c * cos(t / d * (Math_PI / 2)) + c + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
return c * sin(t / d * (Math_PI / 2)) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
return -c / 2 * (cos(Math_PI * t / d) - 1) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace sine
namespace quint {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return c * pow(t / d, 5) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
return c * (pow(t / d - 1, 5) + 1) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
t = t / d * 2;
if (t < 1) {
return c / 2 * pow(t, 5) + b;
}
return c / 2 * (pow(t - 2, 5) + 2) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace quint
namespace quart {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return c * pow(t / d, 4) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
return -c * (pow(t / d - 1, 4) - 1) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
t = t / d * 2;
if (t < 1) {
return c / 2 * pow(t, 4) + b;
}
return -c / 2 * (pow(t - 2, 4) - 2) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace quart
namespace quad {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return c * pow(t / d, 2) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
t /= d;
return -c * t * (t - 2) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
t = t / d * 2;
if (t < 1) {
return c / 2 * pow(t, 2) + b;
}
return -c / 2 * ((t - 1) * (t - 3) - 1) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace quad
namespace expo {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
if (t == 0) {
return b;
}
return c * pow(2, 10 * (t / d - 1)) + b - c * 0.001;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
if (t == d) {
return b + c;
}
return c * 1.001 * (-pow(2, -10 * t / d) + 1) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
if (t == 0) {
return b;
}
if (t == d) {
return b + c;
}
t = t / d * 2;
if (t < 1) {
return c / 2 * pow(2, 10 * (t - 1)) + b - c * 0.0005;
}
return c / 2 * 1.0005 * (-pow(2, -10 * (t - 1)) + 2) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace expo
namespace elastic {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
if (t == 0) {
return b;
}
t /= d;
if (t == 1) {
return b + c;
}
t -= 1;
float p = d * 0.3f;
float a = c * pow(2, 10 * t);
float s = p / 4;
return -(a * sin((t * d - s) * (2 * Math_PI) / p)) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
if (t == 0) {
return b;
}
t /= d;
if (t == 1) {
return b + c;
}
float p = d * 0.3f;
float s = p / 4;
return (c * pow(2, -10 * t) * sin((t * d - s) * (2 * Math_PI) / p) + c + b);
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
if (t == 0) {
return b;
}
if ((t /= d / 2) == 2) {
return b + c;
}
float p = d * (0.3f * 1.5f);
float a = c;
float s = p / 4;
if (t < 1) {
t -= 1;
a *= pow(2, 10 * t);
return -0.5f * (a * sin((t * d - s) * (2 * Math_PI) / p)) + b;
}
t -= 1;
a *= pow(2, -10 * t);
return a * sin((t * d - s) * (2 * Math_PI) / p) * 0.5f + c + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace elastic
namespace cubic {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
t /= d;
return c * t * t * t + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
t = t / d - 1;
return c * (t * t * t + 1) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
t /= d / 2;
if (t < 1) {
return c / 2 * t * t * t + b;
}
t -= 2;
return c / 2 * (t * t * t + 2) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace cubic
namespace circ {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
t /= d;
return -c * (sqrt(1 - t * t) - 1) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
t = t / d - 1;
return c * sqrt(1 - t * t) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
t /= d / 2;
if (t < 1) {
return -c / 2 * (sqrt(1 - t * t) - 1) + b;
}
t -= 2;
return c / 2 * (sqrt(1 - t * t) + 1) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace circ
namespace bounce {
static real_t out(real_t t, real_t b, real_t c, real_t d) {
t /= d;
if (t < (1 / 2.75f)) {
return c * (7.5625f * t * t) + b;
}
if (t < (2 / 2.75f)) {
t -= 1.5f / 2.75f;
return c * (7.5625f * t * t + 0.75f) + b;
}
if (t < (2.5 / 2.75)) {
t -= 2.25f / 2.75f;
return c * (7.5625f * t * t + 0.9375f) + b;
}
t -= 2.625f / 2.75f;
return c * (7.5625f * t * t + 0.984375f) + b;
}
static real_t in(real_t t, real_t b, real_t c, real_t d) {
return c - out(d - t, 0, c, d) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return in(t * 2, b, c / 2, d);
}
return out(t * 2 - d, b + c / 2, c / 2, d);
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace bounce
namespace back {
static real_t in(real_t t, real_t b, real_t c, real_t d) {
float s = 1.70158f;
t /= d;
return c * t * t * ((s + 1) * t - s) + b;
}
static real_t out(real_t t, real_t b, real_t c, real_t d) {
float s = 1.70158f;
t = t / d - 1;
return c * (t * t * ((s + 1) * t + s) + 1) + b;
}
static real_t in_out(real_t t, real_t b, real_t c, real_t d) {
float s = 1.70158f * 1.525f;
t /= d / 2;
if (t < 1) {
return c / 2 * (t * t * ((s + 1) * t - s)) + b;
}
t -= 2;
return c / 2 * (t * t * ((s + 1) * t + s) + 2) + b;
}
static real_t out_in(real_t t, real_t b, real_t c, real_t d) {
if (t < d / 2) {
return out(t * 2, b, c / 2, d);
}
return in(t * 2 - d, b + c / 2, c / 2, d);
}
}; // namespace back
#endif