Code cleanup: rename BLI_math_easing to BLI_easing

Many hard coded values and really specific to time & keyframes.

1 files changed, 314 insertions, 0 deletions

diff --git a/source/blender/blenlib/intern/easing.c b/source/blender/blenlib/intern/easing.c
new file mode 100644
index 00000000000..f3b2efd4680
--- /dev/null
+++ b/source/blender/blenlib/intern/easing.c
@@ -0,0 +1,314 @@
+/*
+ * Copyright © 2001 Robert Penner
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   * Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer.
+ *
+ *   * Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution.
+ *
+ *   * Neither the name of the author nor the names of contributors may be
+ *     used to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL <COPYRIGHT HOLDER> BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** \file blender/blenlib/intern/easing.c
+ *  \ingroup bli
+ */
+ 
+#include <math.h>
+
+#include "BLI_math_base.h"
+
+#include "BLI_easing.h"  /* own include */
+
+#include "BLI_strict_flags.h"
+
+
+float BackEaseIn(float time, float begin, float change, float duration, float overshoot)
+{
+	if (overshoot == 0.0f)
+		overshoot = 1.70158f;
+	time /= duration;
+	return change * time * time * ((overshoot + 1) * time - overshoot) + begin;
+}
+
+float BackEaseOut(float time, float begin, float change, float duration, float overshoot)
+{
+	if (overshoot == 0.0f)
+		overshoot = 1.70158f;
+	time = time / duration - 1;
+	return change * (time * time * ((overshoot + 1) * time + overshoot) + 1) + begin;
+}
+
+float BackEaseInOut(float time, float begin, float change, float duration, float overshoot)
+{
+	if (overshoot == 0.0f)
+		overshoot = 1.70158f; 
+	overshoot *= 1.525f;
+	if ((time /= duration / 2) < 1.0f) {
+		return change / 2 * (time * time * ((overshoot + 1) * time - overshoot)) + begin;
+	}
+	time -= 2.0f;
+	return change / 2 * (time * time * ((overshoot + 1) * time + overshoot) + 2) + begin;
+
+}
+
+float BounceEaseOut(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	if (time < (1 / 2.75f)) {
+		return change * (7.5625f * time * time) + begin;
+	}
+	else if (time < (2 / 2.75f)) {
+		time -= (1.5f / 2.75f);
+		return change * ((7.5625f * time) * time + 0.75f) + begin;
+	}
+	else if (time < (2.5f / 2.75f)) {
+		time -= (2.25f / 2.75f);
+		return change * ((7.5625f * time) * time + 0.9375f) + begin;
+	}
+	else {
+		time -= (2.625f / 2.75f);
+		return change * ((7.5625f * time) * time + 0.984375f) + begin;
+	}
+}
+
+float BounceEaseIn(float time, float begin, float change, float duration)
+{
+	return change - BounceEaseOut(duration - time, 0, change, duration) + begin;
+}
+
+float BounceEaseInOut(float time, float begin, float change, float duration)
+{
+	if (time < duration / 2)
+		return BounceEaseIn(time * 2, 0, change, duration) * 0.5f + begin;
+	else
+		return BounceEaseOut(time * 2 - duration, 0, change, duration) * 0.5f + change * 0.5f + begin;
+}
+
+float CircEaseIn(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return -change * (sqrtf(1 - time * time) - 1) + begin;
+}
+
+float CircEaseOut(float time, float begin, float change, float duration)
+{
+	time = time / duration - 1;
+	return change * sqrtf(1 - time * time) + begin;
+}
+
+float CircEaseInOut(float time, float begin, float change, float duration)
+{
+	if ((time /= duration / 2) < 1.0f)
+		return -change / 2 * (sqrtf(1 - time * time) - 1) + begin;
+	time -= 2.0f;
+	return change / 2 * (sqrtf(1 - time * time) + 1) + begin;
+}
+
+float CubicEaseIn(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return change * time * time * time + begin;
+}
+
+float CubicEaseOut(float time, float begin, float change, float duration)
+{
+	time = time / duration - 1;
+	return change * (time * time * time + 1) + begin;
+}
+
+float CubicEaseInOut(float time, float begin, float change, float duration)
+{
+	if ((time /= duration / 2) < 1.0f)
+		return change / 2 * time * time * time + begin;
+	time -= 2.0f;
+	return change / 2 * (time * time * time + 2) + begin;
+}
+
+float ElasticEaseIn(float time, float begin, float change, float duration, float amplitude, float period)
+{
+	float s;
+
+	if (time == 0.0f)
+		return begin;
+
+	if ((time /= duration) == 1.0f)
+		return begin + change;
+
+	if (!period)
+		period = duration * 0.3f;
+
+	if (!amplitude || amplitude < fabsf(change)) {
+		amplitude = change;
+		s = period / 4;
+	}
+	else
+		s = period / (2 * (float)M_PI) * asinf(change / amplitude);
+
+	time -= 1.0f;
+	return -(amplitude * powf(2, 10 * time) * sinf((time * duration - s) * (2 * (float)M_PI) / period)) + begin;
+}
+
+float ElasticEaseOut(float time, float begin, float change, float duration, float amplitude, float period)
+{
+	float s;
+
+	if (time == 0.0f)
+		return begin;
+	if ((time /= duration) == 1.0f)
+		return begin + change;
+	if (!period)
+		period = duration * 0.3f;
+	if (!amplitude || amplitude < fabsf(change)) {
+		amplitude = change;
+		s = period / 4;
+	}
+	else
+		s = period / (2 * (float)M_PI) * asinf(change / amplitude);
+
+	return (amplitude * powf(2, -10 * time) * sinf((time * duration - s) * (2 * (float)M_PI) / period) + change + begin);
+}
+
+float ElasticEaseInOut(float time, float begin, float change, float duration, float amplitude, float period)
+{
+	float s;
+
+	if (time == 0.0f)
+		return begin;
+	if ((time /= duration / 2) == 2.0f)
+		return begin + change;
+	if (!period)
+		period = duration * (0.3f * 1.5f);
+	if (!amplitude || amplitude < fabsf(change)) {
+		amplitude = change;
+		s = period / 4;
+	}
+	else
+		s = period / (2 * (float)M_PI) * asinf(change / amplitude);
+	if (time < 1.0f) {
+		time -= 1.0f;
+		return -0.5f * (amplitude * powf(2, 10 * time) * sinf((time * duration - s) * (2 * (float)M_PI) / period)) + begin;
+	}
+
+	time -= 1.0f;
+	return amplitude * powf(2, -10 * time) * sinf((time * duration - s) * (2 * (float)M_PI) / period) * 0.5f + change + begin;
+}
+
+float ExpoEaseIn(float time, float begin, float change, float duration)
+{
+	return (time == 0.0f) ? begin : change * powf(2, 10 * (time / duration - 1)) + begin;
+}
+
+float ExpoEaseOut(float time, float begin, float change, float duration)
+{
+	return (time == duration) ? begin + change : change * (-powf(2, -10 * time / duration) + 1) + begin;
+}
+
+float ExpoEaseInOut(float time, float begin, float change, float duration)
+{
+	if (time == 0.0f)
+		return begin;
+	if (time == duration)
+		return begin + change;
+	if ((time /= duration / 2) < 1)
+		return change / 2 * powf(2, 10 * (time - 1)) + begin;
+	time -= 1.0f;
+	return change / 2 * (-powf(2, -10 * time) + 2) + begin;
+}
+
+float LinearEase(float time, float begin, float change, float duration)
+{
+	return change * time / duration + begin;
+}
+
+float QuadEaseIn(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return change * time * time + begin;
+}
+
+float QuadEaseOut(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return -change * time * (time - 2) + begin;
+}
+
+float QuadEaseInOut(float time, float begin, float change, float duration)
+{
+	if ((time /= duration / 2) < 1.0f)
+		return change / 2 * time * time + begin;
+	time -= 1.0f;
+	return -change / 2 * (time * (time - 2) - 1) + begin;
+}
+
+
+float QuartEaseIn(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return change * time * time * time * time + begin;
+}
+
+float QuartEaseOut(float time, float begin, float change, float duration)
+{
+	time = time / duration - 1;
+	return -change * (time * time * time * time - 1) + begin;
+}
+
+float QuartEaseInOut(float time, float begin, float change, float duration)
+{
+	if ((time /= duration / 2) < 1.0f)
+		return change / 2 * time * time * time * time + begin;
+	time -= 2.0f;
+	return -change / 2 * ( time * time * time * time - 2) + begin;
+}
+
+float QuintEaseIn(float time, float begin, float change, float duration)
+{
+	time /= duration;
+	return change * time * time * time * time * time + begin;
+}
+float QuintEaseOut(float time, float begin, float change, float duration)
+{
+	time = time / duration - 1;
+	return change * (time * time * time * time * time + 1) + begin;
+}
+float QuintEaseInOut(float time, float begin, float change, float duration)
+{
+	if ((time /= duration / 2) < 1.0f)
+		 return change / 2 * time * time * time * time * time + begin;
+	time -= 2.0f;
+	return change / 2 * (time * time * time * time * time + 2) + begin;
+}
+
+float SineEaseIn(float time, float begin, float change, float duration)
+{
+	return -change * cosf(time / duration * (float)M_PI_2) + change + begin;
+}
+
+float SineEaseOut(float time, float begin, float change, float duration)
+{
+	return change * sinf(time / duration * (float)M_PI_2) + begin;
+}
+
+float SineEaseInOut(float time, float begin, float change, float duration)
+{
+	return -change / 2 * (cosf((float)M_PI * time / duration) - 1) + begin;
+}