apophysis7x/Plugin/flux.c

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/*
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.
*/
/*
09-10-04 - Optimized by Xyrus02
*/
typedef struct
{
//double v;
double spr;
double flux_spread;
} Variables;
#include "apoplugin.h"
APO_PLUGIN("flux");
APO_VARIABLES(
VAR_REAL(flux_spread, 0.0),
);
int PluginVarPrepare(Variation* vp)
{
// Why is this calculated? It isn't used...
//VAR(v) = 0.5 * VVAR / M_PI;
// But we only use 2 + VAR(flux_spread) so we can precalculate that :-)
VAR(spr) = 2 + VAR(flux_spread);
// We succeeded :-)
return TRUE;
}
int PluginVarCalc(Variation* vp)
{
double avgr, avga;
double s, c;
// Avoid reduant calculations by precalculating everything what is used at least twice
double x = FTx,
y = FTy;
double xpv = FTx + VVAR,
xmv = FTx - VVAR;
double y2 = sqr(y);
// We have a division by zero problem in the original flux
// (What if y + (x-vvar) == 0 ????)
double frac = sqrt(y2 + sqr(xmv));
if (frac == 0) frac = 1.0;
// This is a huge shitload of calculations :O
avgr = VVAR * (VAR(spr) * sqrt(sqrt(y2 + sqr(xpv) ) / frac));
avga = (atan2(y , xmv) - atan2(y , xpv)) / 2.0;
fsincos(avga, &s, &c);
FPx += avgr * c;
FPy += avgr * s;
// Add 3D compatibility
FPz += FTz;
// Report success!
return TRUE;
}