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/*
* Part of fractal-gen - Generate iteration-based fractals in PNM format
* Copyright (c) 2015 David Phillips <dbphillipsnz@gmail.com>
* All rights reserved
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "../fractal-gen.h"
void *generate_mandelbrot_section(void *section)
{
data_section *d = (data_section*)section;
unsigned int x,y,i;
int idx = 0;
double a,b;
double complex z,c;
double size_units = 3.5f;
double top = -1.75f;
double left = -2.5f;
for (y = d->core, b = (d->core*(size_units/d->size)+top); y < d->size; b+=((d->cores*size_units)/d->size), y+=d->cores)
{
for (x = d->clust_id, a = (d->clust_id*(size_units/d->size)+left); x < d->size; a+=((d->clust_total*size_units)/d->size), x+=d->clust_total)
{
z = 0;
c = a+I*b;
for (i = 0; i < d->iterat; i++)
{
if (cabsf(z) >= 2)
break;
z = cpow(z , d->power) + c;
}
d->data[idx++] = (255*i)/d->iterat;
}
}
return NULL;
}
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