ugfx/demos/applications/mandelbrot/main.c

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2021-10-20 12:17:27 +00:00
/*
* Copyright (c) 2012, 2013, Joel Bodenmann aka Tectu <joel@unormal.org>
* Copyright (c) 2012, 2013, Andrew Hannam aka inmarket
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name of the <organization> nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 <COPYRIGHT HOLDER> 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 "gfx.h"
void mandelbrot(float x1, float y1, float x2, float y2) {
unsigned int i,j, width, height;
gU16 iter;
gColor color;
float fwidth, fheight;
float sy = y2 - y1;
float sx = x2 - x1;
const int MAX = 512;
width = (unsigned int)gdispGetWidth();
height = (unsigned int)gdispGetHeight();
fwidth = width;
fheight = height;
for(i = 0; i < width; i++) {
for(j = 0; j < height; j++) {
float cy = j * sy / fheight + y1;
float cx = i * sx / fwidth + x1;
float x=0.0f, y=0.0f, xx=0.0f, yy=0.0f;
for(iter=0; iter <= MAX && xx+yy<4.0f; iter++) {
xx = x*x;
yy = y*y;
y = 2.0f*x*y + cy;
x = xx - yy + cx;
}
//color = ((iter << 8) | (iter&0xFF));
color = RGB2COLOR(iter<<7, iter<<4, iter);
gdispDrawPixel(i, j, color);
}
}
}
int main(void) {
float cx, cy;
float zoom = 1.0f;
gfxInit();
/* where to zoom in */
cx = -0.086f;
cy = 0.85f;
while(1) {
mandelbrot(-2.0f*zoom+cx, -1.5f*zoom+cy, 2.0f*zoom+cx, 1.5f*zoom+cy);
zoom *= 0.7f;
if(zoom <= 0.00001f)
zoom = 1.0f;
}
}