apophysis7x/Plugin/cpow2.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

85 lines
2.4 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.
*/
// Must define this structure before we include apoplugin.h
typedef struct
{
double cpow2_r, cpow2_a;
int cpow2_divisor;
int cpow2_spread;
double c, half_c;
double d, half_d;
double ang;
double inv_spread, full_spread;
} Variables;
#define _USE_MATH_DEFINES
#include "apoplugin.h"
// Set the name of this plugin
APO_PLUGIN("cpow2");
// Define the Variables
APO_VARIABLES(
VAR_REAL(cpow2_r, 1.0),
VAR_REAL(cpow2_a, 0.0),
VAR_INTEGER_NONZERO(cpow2_divisor, 1),
VAR_INTEGER_RANGE(cpow2_spread, 1, 0x7fffffff, 1),
);
// You must call the argument "vp".
int PluginVarPrepare(Variation* vp)
{
VAR(ang) = 2*M_PI / ((double) VAR(cpow2_divisor));
VAR(c) = VAR(cpow2_r) * cos(M_PI/2*VAR(cpow2_a)) / ((double) VAR(cpow2_divisor));
VAR(d) = VAR(cpow2_r) * sin(M_PI/2*VAR(cpow2_a)) / ((double) VAR(cpow2_divisor));
VAR(half_c) = VAR(c) / 2;
VAR(half_d) = VAR(d) / 2;
VAR(inv_spread) = 0.5 / VAR(cpow2_spread);
VAR(full_spread) = 2*M_PI*VAR(cpow2_spread);
return TRUE; // Always return TRUE.
}
// You must call the argument "vp".
int PluginVarCalc(Variation* vp)
{
double sn, cs;
double a = atan2(FTy, FTx);
int n = rand() % VAR(cpow2_spread);
if (a < 0) n++;
a += 2*M_PI*n;
if (cos(a*VAR(inv_spread)) < rand()*2.0/RAND_MAX - 1.0)
a -= VAR(full_spread);
double lnr2 = log(FTx*FTx + FTy*FTy); // logarithm * 2
double r = VVAR * exp(VAR(half_c) * lnr2 - VAR(d) * a);
fsincos(VAR(c) * a + VAR(half_d) * lnr2 + VAR(ang) * rand(),
&sn, &cs);
FPx += r * cs;
FPy += r * sn;
return TRUE;
}