--- /dev/null
+/* swfc- Compiles swf code (.sc) files into .swf files.
+
+ Part of the swftools package.
+
+ Copyright (c) 2007 Huub Schaeks <huub@h-schaeks.speedlinq.nl>
+ Copyright (c) 2007 Matthias Kramm <kramm@quiss.org>
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
+
+#include <stdlib.h>
+#include <math.h>
+#include <memory.h>
+#include "interpolation.h"
+
+static inline float poly(float fraction, float start, float delta, int degree)
+{
+ return delta * pow(fraction, degree) + start;
+}
+
+float linear(float fraction, float start, float delta)
+{
+ return poly(fraction, start, delta, 1);
+}
+
+float quadIn(float fraction, float start, float delta)
+{
+ return poly(fraction, start, delta, 2);
+}
+
+float quadOut(float fraction, float start, float delta)
+{
+ return quadIn(1 - fraction, start + delta, -delta);
+}
+
+float quadInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return quadIn(2 * fraction, start, delta / 2);
+ return quadOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float cubicIn(float fraction, float start, float delta)
+{
+ return poly(fraction, start, delta, 3);
+}
+
+float cubicOut(float fraction, float start, float delta)
+{
+ return cubicIn(1 - fraction, start + delta, -delta);
+}
+
+float cubicInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return cubicIn(2 * fraction, start, delta / 2);
+ return cubicOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float quartIn(float fraction, float start, float delta)
+{
+ return poly(fraction, start, delta, 4);
+}
+
+float quartOut(float fraction, float start, float delta)
+{
+ return quartIn(1 - fraction, start + delta, -delta);
+}
+
+float quartInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return quartIn(2 * fraction, start, delta / 2);
+ return quartOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float quintIn(float fraction, float start, float delta)
+{
+ return poly(fraction, start, delta, 5);
+}
+
+float quintOut(float fraction, float start, float delta)
+{
+ return quintIn(1 - fraction, start + delta, -delta);
+}
+
+float quintInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return quintIn(2 * fraction, start, delta / 2);
+ return quintOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float circleIn(float fraction, float start, float delta)
+{
+ return delta * (1 - sqrt(1 - fraction * fraction)) + start;
+}
+
+float circleOut(float fraction, float start, float delta)
+{
+ return circleIn(1 - fraction, start + delta, -delta);
+}
+
+float circleInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return circleIn(2 * fraction, start, delta / 2);
+ return circleOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float exponentialIn(float fraction, float start, float delta)
+{
+ if (fraction == 0)
+ return start;
+ return delta * pow(2, 10 * (fraction - 1)) + start;
+}
+
+float exponentialOut(float fraction, float start, float delta)
+{
+ return exponentialIn(1 - fraction, start + delta, -delta);
+}
+
+float exponentialInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return exponentialIn(2 * fraction, start, delta / 2);
+ return exponentialOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float sineIn(float fraction, float start, float delta)
+{
+ return delta * (1 - cos(fraction * PI/2)) + start;
+}
+
+float sineOut(float fraction, float start, float delta)
+{
+ return sineIn(1 - fraction, start + delta, -delta);
+}
+
+float sineInOut(float fraction, float start, float delta)
+{
+ if (fraction < 0.5)
+ return sineIn(2 * fraction, start, delta / 2);
+ return sineOut(2 * fraction - 1, start + delta / 2, delta / 2);
+}
+
+float elasticIn(float fraction, float start, float delta, float amplitude, int bounces, float damping)
+{
+ if (fraction == 0 || delta == 0)
+ return start;
+ if (fraction == 1)
+ return start + delta;
+ if (amplitude < fabs(delta))
+ amplitude = delta;
+ float period = 1 / (bounces + 0.25);
+// float s = asin(delta / amplitude) - 2 * PI / period;
+ return amplitude * pow(2, damping * (fraction - 1)) * sin(fraction * (2 * PI) / period /*+ fraction * s*/) + start;
+}
+
+float elasticOut(float fraction, float start, float delta, float amplitude, int bounces, float damping)
+{
+ return elasticIn(1 - fraction, start + delta, -delta, amplitude, bounces, damping);
+}
+
+float elasticInOut(float fraction, float start, float delta, float amplitude, int bounces, float damping)
+{
+ if (fraction < 0.5)
+ return elasticIn(2 * fraction, start, delta / 2, amplitude, bounces, damping);
+ return elasticOut(2 * fraction - 1, start + delta / 2, delta / 2, amplitude, bounces, damping);
+}
+
+float backIn(float fraction, float start, float delta, float speed)
+{
+ return delta * fraction * fraction * ((speed + 1) * fraction - speed) + start;
+}
+
+float backOut(float fraction, float start, float delta, float speed)
+{
+ return backIn(1 - fraction, start + delta, -delta, speed);
+}
+
+float backInOut(float fraction, float start, float delta, float speed)
+{
+ if (fraction < 0.5)
+ return backIn(2 * fraction, start, delta / 2, speed);
+ return backOut(2 * fraction - 1, start + delta / 2, delta / 2, speed);
+}
+
+/* when applied to movement bounceIn the object 'hits the floor' bounces times
+ * (after leaving the floor first) before gently reaching the final position at the top of the final bounce
+ * Each bounce takes growth times a long as the previous, except for the last one which lasts only half
+ * that time. The heights of the intermediate bounces are determined by the damping parameter.
+ * Set damping to 0 for an undamped movement.*/
+
+float bounceIn(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ if (fraction == 0 || delta == 0)
+ return start;
+ if (fraction == 1)
+ return start + delta;
+ float w0;
+ if (growth == 1.0)
+ w0 = 1 / (bounces + 0.5);
+ else
+ {
+ float gN = pow(growth, bounces);
+ w0 = 1 / ((gN - 1) / (growth - 1) + gN / 2 );
+ }
+ float bounceStart = 0;
+ int i;
+ float w = w0;
+ for (i = 0; i <= bounces; i++)
+ {
+ float bounceEnd = bounceStart + w;
+ if (fraction >= bounceStart && fraction < bounceEnd)
+ {
+ float half = (bounceEnd + bounceStart) / 2;
+ float top = delta / pow(2, damping * ((bounces - i)));
+ fraction -= half;
+ fraction /= (w / 2);
+ return (1 - fraction * fraction) * top + start;
+ }
+ bounceStart = bounceEnd;
+ w = w * growth;
+ }
+}
+
+/* bounceOut is a time-reversed bounceIn; therefore each bounce takes 1/growth times as long as
+ * the previous, which I think fits the idea when applied to movement */
+
+float bounceOut(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ return bounceIn(1 - fraction, start + delta, -delta, bounces, growth, damping);
+}
+
+/* since bounceIn and bounceOut are combined, if growth > 1 then the bounce-times will increase in
+ * the first half and decrease in the second half */
+
+float bounceInOut(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ if (fraction < 0.5)
+ return bounceIn(2 * fraction, start, delta / 2, bounces, growth, damping);
+ return bounceOut(2 * fraction - 1, start + delta / 2, delta / 2, bounces, growth, damping);
+}
+/* fastBounce(In/Out) doesn't end or start in a horizontal slope (= gentle end or start) as
+ * bounce(In/Out) do which means fastBounceInOut doesn't have the 'delay' in the middle */
+float fastBounceIn(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ if (fraction == 0 || delta == 0)
+ return start;
+ if (fraction == 1)
+ return start + delta;
+ float w0;
+ if (growth == 1.0)
+ w0 = 1 / (bounces + 0.25); /* in general (bounces + 1 / (2 * f)) */
+ else
+ {
+ float gN = pow(growth, bounces);
+ w0 = 1 / ((gN - 1) / (growth - 1) + gN / 4 /* in general: gN / (2 * f) */ );
+ }
+ float bounceStart = 0;
+ int i;
+ float w = w0;
+ for (i = 0; i <= bounces; i++)
+ {
+ float bounceEnd = bounceStart + w;
+ if (fraction >= bounceStart && fraction < bounceEnd)
+ {
+ float half = (bounceEnd + bounceStart) / 2;
+ float top = delta / 0.75/* in general: (1 - (1 / f) * (1 / f)) */ / pow(2, damping * ((bounces - i)));
+ fraction -= half;
+ fraction /= (w / 2);
+ return (1 - fraction * fraction) * top + start;
+ }
+ bounceStart = bounceEnd;
+ w = w * growth;
+ }
+}
+
+float fastBounceOut(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ return fastBounceIn(1 - fraction, start + delta, -delta, bounces, growth, damping);
+}
+
+float fastBounceInOut(float fraction, float start, float delta, int bounces, float growth, float damping)
+{
+ if (fraction < 0.5)
+ return fastBounceIn(2 * fraction, start, delta / 2, bounces, growth, damping);
+ return fastBounceOut(2 * fraction - 1, start + delta / 2, delta / 2, bounces, growth, damping);
+}