apophysis7x/Plugin/fibonacci.c
xyrus02 95a2f54683 ADMIN: migration complete
git-svn-id: https://svn.code.sf.net/p/apophysis7x/svn/trunk@1 a5d1c0f9-a0e9-45c6-87dd-9d276e40c949
2013-07-28 08:58:33 +00:00

82 lines
2.5 KiB
C

/*
Apophysis Plugin
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., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
typedef struct
{
double ffive;
double fnatlog;
} Variables;
#define _USE_MATH_DEFINES
#define APO_NOVARIABLES
#define APO_VIRTUALVAR
#include "apoplugin.h"
// Set the name of this plugin
APO_PLUGIN("fibonacci");
// You must call the argument "vp".
int PluginVarPrepare(Variation* vp)
{
// Updated to use the new constants. Still calculates
// invserse of root five and the nat log of the Golden Ratio.
// I'm not sure how many decimal places were appropriate,
// or how many C allows, and this isn't going to take
// up any noticeable amount of time.
VAR(ffive) = 1/M_SQRT5;
VAR(fnatlog) = log(M_PHI);
// Always return TRUE.
return TRUE;
}
// p^z - (-p)^(-z)
// z' = -----------------
// sqrt(5)
//
// Where p is the Golden Ratio.
// This function generates the fibonacci sequence
// for real integer values.
// 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 < Real Value
// 1 1 2 3 5 8 13 21 34 55 89 144 233 377 610 < Fib Value
//
// Negative real integers produce the negative fibonacci sequence,
// which is the same as the normal one, except every
// other number is negative.
// 1 0 -1 -2 -3 -4 -5 -6 -7 -8 < Real Value
// 1 0 1 -1 3 -3 5 -8 13 -21 < Fib Value
// You must call the argument "vp".
int PluginVarCalc(Variation* vp)
{
double snum1, cnum1, snum2, cnum2;
fsincos(FTy * VAR(fnatlog), &snum1, &cnum1);
fsincos((FTx * M_PI + FTy * VAR(fnatlog)) * -1, &snum2, &cnum2);
double eradius1 = exp(FTx * VAR(fnatlog));
double eradius2 = exp((FTx * VAR(fnatlog) - FTy * M_PI) * -1);
FPx += VVAR * (eradius1 * cnum1 - eradius2 * cnum2) * VAR(ffive);
FPy += VVAR * (eradius1 * snum1 - eradius2 * snum2) * VAR(ffive);
return TRUE;
}