/* gtd-easing.c * * Copyright 2020 Georges Basile Stavracas Neto * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . * * SPDX-License-Identifier: GPL-3.0-or-later */ #include "gtd-easing.h" #include gdouble gtd_linear (gdouble t, gdouble d) { return t / d; } gdouble gtd_ease_in_quad (gdouble t, gdouble d) { gdouble p = t / d; return p * p; } gdouble gtd_ease_out_quad (gdouble t, gdouble d) { gdouble p = t / d; return -1.0 * p * (p - 2); } gdouble gtd_ease_in_out_quad (gdouble t, gdouble d) { gdouble p = t / (d / 2); if (p < 1) return 0.5 * p * p; p -= 1; return -0.5 * (p * (p - 2) - 1); } gdouble gtd_ease_in_cubic (gdouble t, gdouble d) { gdouble p = t / d; return p * p * p; } gdouble gtd_ease_out_cubic (gdouble t, gdouble d) { gdouble p = t / d - 1; return p * p * p + 1; } gdouble gtd_ease_in_out_cubic (gdouble t, gdouble d) { gdouble p = t / (d / 2); if (p < 1) return 0.5 * p * p * p; p -= 2; return 0.5 * (p * p * p + 2); } gdouble gtd_ease_in_quart (gdouble t, gdouble d) { gdouble p = t / d; return p * p * p * p; } gdouble gtd_ease_out_quart (gdouble t, gdouble d) { gdouble p = t / d - 1; return -1.0 * (p * p * p * p - 1); } gdouble gtd_ease_in_out_quart (gdouble t, gdouble d) { gdouble p = t / (d / 2); if (p < 1) return 0.5 * p * p * p * p; p -= 2; return -0.5 * (p * p * p * p - 2); } gdouble gtd_ease_in_quint (gdouble t, gdouble d) { gdouble p = t / d; return p * p * p * p * p; } gdouble gtd_ease_out_quint (gdouble t, gdouble d) { gdouble p = t / d - 1; return p * p * p * p * p + 1; } gdouble gtd_ease_in_out_quint (gdouble t, gdouble d) { gdouble p = t / (d / 2); if (p < 1) return 0.5 * p * p * p * p * p; p -= 2; return 0.5 * (p * p * p * p * p + 2); } gdouble gtd_ease_in_sine (gdouble t, gdouble d) { return -1.0 * cos (t / d * G_PI_2) + 1.0; } gdouble gtd_ease_out_sine (gdouble t, gdouble d) { return sin (t / d * G_PI_2); } gdouble gtd_ease_in_out_sine (gdouble t, gdouble d) { return -0.5 * (cos (G_PI * t / d) - 1); } gdouble gtd_ease_in_expo (gdouble t, gdouble d) { return (t == 0) ? 0.0 : pow (2, 10 * (t / d - 1)); } gdouble gtd_ease_out_expo (gdouble t, gdouble d) { return (t == d) ? 1.0 : -pow (2, -10 * t / d) + 1; } gdouble gtd_ease_in_out_expo (gdouble t, gdouble d) { gdouble p; if (t == 0) return 0.0; if (t == d) return 1.0; p = t / (d / 2); if (p < 1) return 0.5 * pow (2, 10 * (p - 1)); p -= 1; return 0.5 * (-pow (2, -10 * p) + 2); } gdouble gtd_ease_in_circ (gdouble t, gdouble d) { gdouble p = t / d; return -1.0 * (sqrt (1 - p * p) - 1); } gdouble gtd_ease_out_circ (gdouble t, gdouble d) { gdouble p = t / d - 1; return sqrt (1 - p * p); } gdouble gtd_ease_in_out_circ (gdouble t, gdouble d) { gdouble p = t / (d / 2); if (p < 1) return -0.5 * (sqrt (1 - p * p) - 1); p -= 2; return 0.5 * (sqrt (1 - p * p) + 1); } gdouble gtd_ease_in_elastic (gdouble t, gdouble d) { gdouble p = d * .3; gdouble s = p / 4; gdouble q = t / d; if (q == 1) return 1.0; q -= 1; return -(pow (2, 10 * q) * sin ((q * d - s) * (2 * G_PI) / p)); } gdouble gtd_ease_out_elastic (gdouble t, gdouble d) { gdouble p = d * .3; gdouble s = p / 4; gdouble q = t / d; if (q == 1) return 1.0; return pow (2, -10 * q) * sin ((q * d - s) * (2 * G_PI) / p) + 1.0; } gdouble gtd_ease_in_out_elastic (gdouble t, gdouble d) { gdouble p = d * (.3 * 1.5); gdouble s = p / 4; gdouble q = t / (d / 2); if (q == 2) return 1.0; if (q < 1) { q -= 1; return -.5 * (pow (2, 10 * q) * sin ((q * d - s) * (2 * G_PI) / p)); } else { q -= 1; return pow (2, -10 * q) * sin ((q * d - s) * (2 * G_PI) / p) * .5 + 1.0; } } gdouble gtd_ease_in_back (gdouble t, gdouble d) { gdouble p = t / d; return p * p * ((1.70158 + 1) * p - 1.70158); } gdouble gtd_ease_out_back (gdouble t, gdouble d) { gdouble p = t / d - 1; return p * p * ((1.70158 + 1) * p + 1.70158) + 1; } gdouble gtd_ease_in_out_back (gdouble t, gdouble d) { gdouble p = t / (d / 2); gdouble s = 1.70158 * 1.525; if (p < 1) return 0.5 * (p * p * ((s + 1) * p - s)); p -= 2; return 0.5 * (p * p * ((s + 1) * p + s) + 2); } static inline gdouble ease_out_bounce_internal (gdouble t, gdouble d) { gdouble p = t / d; if (p < (1 / 2.75)) { return 7.5625 * p * p; } else if (p < (2 / 2.75)) { p -= (1.5 / 2.75); return 7.5625 * p * p + .75; } else if (p < (2.5 / 2.75)) { p -= (2.25 / 2.75); return 7.5625 * p * p + .9375; } else { p -= (2.625 / 2.75); return 7.5625 * p * p + .984375; } } static inline gdouble ease_in_bounce_internal (gdouble t, gdouble d) { return 1.0 - ease_out_bounce_internal (d - t, d); } gdouble gtd_ease_in_bounce (gdouble t, gdouble d) { return ease_in_bounce_internal (t, d); } gdouble gtd_ease_out_bounce (gdouble t, gdouble d) { return ease_out_bounce_internal (t, d); } gdouble gtd_ease_in_out_bounce (gdouble t, gdouble d) { if (t < d / 2) return ease_in_bounce_internal (t * 2, d) * 0.5; else return ease_out_bounce_internal (t * 2 - d, d) * 0.5 + 1.0 * 0.5; } /*< private > * _gtd_animation_modes: * * A mapping of animation modes and easing functions. */ static const struct { GtdEaseMode mode; GtdEaseFunc func; const char *name; } _gtd_animation_modes[] = { { GTD_CUSTOM_MODE, NULL, "custom" }, { GTD_EASE_LINEAR, gtd_linear, "linear" }, { GTD_EASE_IN_QUAD, gtd_ease_in_quad, "easeInQuad" }, { GTD_EASE_OUT_QUAD, gtd_ease_out_quad, "easeOutQuad" }, { GTD_EASE_IN_OUT_QUAD, gtd_ease_in_out_quad, "easeInOutQuad" }, { GTD_EASE_IN_CUBIC, gtd_ease_in_cubic, "easeInCubic" }, { GTD_EASE_OUT_CUBIC, gtd_ease_out_cubic, "easeOutCubic" }, { GTD_EASE_IN_OUT_CUBIC, gtd_ease_in_out_cubic, "easeInOutCubic" }, { GTD_EASE_IN_QUART, gtd_ease_in_quart, "easeInQuart" }, { GTD_EASE_OUT_QUART, gtd_ease_out_quart, "easeOutQuart" }, { GTD_EASE_IN_OUT_QUART, gtd_ease_in_out_quart, "easeInOutQuart" }, { GTD_EASE_IN_QUINT, gtd_ease_in_quint, "easeInQuint" }, { GTD_EASE_OUT_QUINT, gtd_ease_out_quint, "easeOutQuint" }, { GTD_EASE_IN_OUT_QUINT, gtd_ease_in_out_quint, "easeInOutQuint" }, { GTD_EASE_IN_SINE, gtd_ease_in_sine, "easeInSine" }, { GTD_EASE_OUT_SINE, gtd_ease_out_sine, "easeOutSine" }, { GTD_EASE_IN_OUT_SINE, gtd_ease_in_out_sine, "easeInOutSine" }, { GTD_EASE_IN_EXPO, gtd_ease_in_expo, "easeInExpo" }, { GTD_EASE_OUT_EXPO, gtd_ease_out_expo, "easeOutExpo" }, { GTD_EASE_IN_OUT_EXPO, gtd_ease_in_out_expo, "easeInOutExpo" }, { GTD_EASE_IN_CIRC, gtd_ease_in_circ, "easeInCirc" }, { GTD_EASE_OUT_CIRC, gtd_ease_out_circ, "easeOutCirc" }, { GTD_EASE_IN_OUT_CIRC, gtd_ease_in_out_circ, "easeInOutCirc" }, { GTD_EASE_IN_ELASTIC, gtd_ease_in_elastic, "easeInElastic" }, { GTD_EASE_OUT_ELASTIC, gtd_ease_out_elastic, "easeOutElastic" }, { GTD_EASE_IN_OUT_ELASTIC, gtd_ease_in_out_elastic, "easeInOutElastic" }, { GTD_EASE_IN_BACK, gtd_ease_in_back, "easeInBack" }, { GTD_EASE_OUT_BACK, gtd_ease_out_back, "easeOutBack" }, { GTD_EASE_IN_OUT_BACK, gtd_ease_in_out_back, "easeInOutBack" }, { GTD_EASE_IN_BOUNCE, gtd_ease_in_bounce, "easeInBounce" }, { GTD_EASE_OUT_BOUNCE, gtd_ease_out_bounce, "easeOutBounce" }, { GTD_EASE_IN_OUT_BOUNCE, gtd_ease_in_out_bounce, "easeInOutBounce" }, { GTD_EASE_LAST, NULL, "sentinel" }, }; GtdEaseFunc gtd_get_easing_func_for_mode (GtdEaseMode mode) { g_assert (_gtd_animation_modes[mode].mode == mode); g_assert (_gtd_animation_modes[mode].func != NULL); return _gtd_animation_modes[mode].func; } const char * gtd_get_easing_name_for_mode (GtdEaseMode mode) { g_assert (_gtd_animation_modes[mode].mode == mode); g_assert (_gtd_animation_modes[mode].func != NULL); return _gtd_animation_modes[mode].name; } gdouble gtd_easing_for_mode (GtdEaseMode mode, gdouble t, gdouble d) { g_assert (_gtd_animation_modes[mode].mode == mode); g_assert (_gtd_animation_modes[mode].func != NULL); return _gtd_animation_modes[mode].func (t, d); }