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puzzles: more accurate sin() and cos()

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- now uses fp_sincos()

Change-Id: I20c8224cac98fc677097161737d25dd9038bede2
This commit is contained in:
Franklin Wei 2017-01-16 11:38:18 -05:00 committed by Franklin Wei
parent 1b882cb156
commit 0056ea8a25
1 changed files with 36 additions and 7 deletions
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43
apps/plugins/puzzles/rbwrappers.c
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@ -22,24 +22,53 @@ int puts_wrapper(const char *s)
}
/* fixed-point wrappers */
static long lastphase = 0, lastsin = 0, lastcos = 0x7fffffff;
double sin_wrapper(double rads)
{
int degs = rads * 180/PI;
long fixed = fp14_sin(degs);
return fixed / (16384.0);
/* we want [0, 2*PI) */
while(rads >= 2*PI)
rads -= 2*PI;
while(rads < 0)
rads += 2*PI;
unsigned long phase = rads/(2*PI) * 4294967296.0;
/* caching */
if(phase == lastphase)
{
return lastsin/(lastsin < 0 ? 2147483648.0 : 2147483647.0);
}
lastphase = phase;
lastsin = fp_sincos(phase, &lastcos);
return lastsin/(lastsin < 0 ? 2147483648.0 : 2147483647.0);
}
double cos_wrapper(double rads)
{
int degs = rads * 180/PI;
long fixed = fp14_cos(degs);
return fixed / (16384.0);
/* we want [0, 2*PI) */
while(rads >= 2*PI)
rads -= 2*PI;
while(rads < 0)
rads += 2*PI;
unsigned long phase = rads/(2*PI) * 4294967296.0;
/* caching */
if(phase == lastphase)
{
return lastcos/(lastcos < 0 ? 2147483648.0 : 2147483647.0);
}
lastphase = phase;
lastsin = fp_sincos(phase, &lastcos);
return lastcos/(lastcos < 0 ? 2147483648.0 : 2147483647.0);
}
int vsprintf_wrapper(char *s, const char *fmt, va_list ap)
{
return rb->vsnprintf(s, 9999, fmt, ap);
}
/* Absolute value, simple calculus */