51 lines
1.8 KiB
C
51 lines
1.8 KiB
C
#include "tricorn.h"
|
|
|
|
static const float convergenceLimit = 2.0f; // Mandelbrot set limit
|
|
static unsigned converge(float complex position,unsigned n);
|
|
|
|
void tricorn(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img){
|
|
|
|
// Absolute height for iteration purposes
|
|
height = height < 0 ? height*-1 : height;
|
|
|
|
// Simple iteration over every pixel in the picture
|
|
for(size_t i = 0; i < width; i++){
|
|
for(ssize_t j = 0; j < height; j++){
|
|
|
|
unsigned value = converge(start + (i*res - I*j*res),n);
|
|
|
|
// Pixel value position in the output array
|
|
size_t position = (j*width +i) *3;
|
|
|
|
|
|
if(!color){ // Grayscale colors as specified by the assignment r = g = b
|
|
img[position] = value;
|
|
img[position + 1] = value;
|
|
img[position + 2] = value;
|
|
}
|
|
else{ // Temporary colors with random multipliers
|
|
img[position] = ((value*3) % 255);
|
|
img[position + 1] = ((value*2) % 255) ;
|
|
img[position + 2] = ((value*5) % 255);
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
// Iterative application of the equation given by the assignment
|
|
static unsigned converge(float complex position,unsigned n){
|
|
|
|
complex float result = 0;
|
|
for(unsigned i = 0; i < n; i++){
|
|
// Application of the given complex equation with m = 2
|
|
result = cpowf(conjf(result),2) + position;
|
|
|
|
// Detection of unbounded behaviour
|
|
// If the magnitude of the result vector is greater than the convergence limit, we know that the function will grow unbounded
|
|
// Current convergence limit taken from mandelbrot set
|
|
if(sqrtf(powf (crealf(result),2)+powf(cimagf(result),2)) > convergenceLimit)
|
|
return 255-4*(i % 64);
|
|
}
|
|
return 0;
|
|
} |