Fixed tricorn_V3.c to correctly handle complex numbers and add threaded V4 skeleton

This commit is contained in:
Yashar Alan Zenker
2026-07-04 15:28:51 +02:00
parent c1bbaf7eda
commit b630fa965e
4 changed files with 93 additions and 8 deletions
+8 -4
View File
@@ -9,6 +9,7 @@
#include "tricorn_V1.h"
#include "tricorn_V2.h"
#include "tricorn_V3.h"
#include "tricorn_V4.h"
void save_bmp(const char *filename, unsigned char *img, size_t width, ssize_t height,_Bool color);
@@ -206,7 +207,7 @@ int main(int argc, char** argv)
switch (version_to_use)
{
case 0:
//Uses highly optimized SIMD version
// Uses highly optimized SIMD version
tricorn_V0(complexA,width,height,resolution,n,colored,tempArr);
break;
case 1:
@@ -214,14 +215,17 @@ int main(int argc, char** argv)
tricorn_V1(complexA,width,height,resolution,n,colored,tempArr);
break;
case 2:
//Uses optimized SISD version
// Uses optimized SISD version
tricorn_V2(complexA,width,height,resolution,n,colored,tempArr);
break;
case 3:
//Uses unoptimised comparison implementation
// Uses unoptimised comparison implementation
tricorn_V3(complexA,width,height,resolution,n,colored,tempArr);
break;
case 4:
// Uses non SIMD threaded version
tricorn_V4(complexA,width,height,resolution,n,colored,tempArr);
break;
default:
break;
}
+3 -4
View File
@@ -15,16 +15,15 @@ static unsigned converge(float complex position,unsigned n);
*/
void tricorn_V3(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img){
// Absolute height for iteration purposes
unsigned imag_direction = height < 0 ? -1 : 1;
height = height < 0 ? height*-1 : height;
float imag_direction = height < 0 ? -1.0f : 1.0f;
unsigned bytesPerColor = color ? 3 : 1;
height = height < 0? -height : 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 - imag_direction*j*res),n);
unsigned value = converge(start + (i*res - I* imag_direction*j*res),n);
// Pixel value position in the output array
size_t position = (j*width +i) * bytesPerColor;
+77
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@@ -0,0 +1,77 @@
#include "tricorn_V2.h"
static unsigned converge(float c_real, float c_imag, unsigned n);
/**
* @brief Generates a Tricorn fractal image using an optimized SISD implementation.
* @param start The starting complex coordinate (bottom-left or top-left depending on height sign).
* @param width The width of the target image in pixels.
* @param height The height of the target image. A negative height reverses the Y-axis calculation.
* @param res The step size (resolution) per pixel in the complex plane.
* @param n The maximum number of mathematical iterations per pixel.
* @param color If true, generates a 24-bit RGB image. If false, writes a grayscale image.
* @param img Pointer to the pre-allocated memory buffer where the bitmap data will be stored.
*/
void tricorn_V4(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img){
int bytesPerColor = color ? 3 : 1;
// Absolute height for iteration purposes
ssize_t actual_height = height < 0 ? (ssize_t)(-height) : height;
ssize_t imag_step = height < 0 ? -1:1;
float c_start_real = creal(start);
float c_start_imag = cimag(start);
float c_imag = c_start_imag;
float vertical_step = imag_step * res;
size_t position = 0;
// Simple iteration over every pixel in the picture
for(ssize_t y = 0; y < actual_height; y++){
// Calculate imaginary part on each row as it stays the same
float c_real = c_start_real;
for(size_t x = 0; x < width; x++){
unsigned value = converge(c_real,c_imag,n);
// Pixel value position in the output array
if(!color){ // Grayscale colors as specified by the assignment r = g = b
img[position] = value;
}
else{ // Temporary colors with random multipliers
img[position] = ((value*3) % 255);
img[position + 1] = ((value*2) % 255) ;
img[position + 2] = ((value*5) % 255);
}
position += bytesPerColor;
c_real += res;
}
c_imag -= vertical_step;
}
}
// Iterative application of the equation given by the assignment
static inline unsigned converge(float c_real, float c_imag, unsigned n) {
const float convergenceLimit = 4.0f;
float real = 0.0f;
float imag = 0.0f;
for (unsigned i = 0; i < n; i++) {
float real2 = real * real;
float imag2 = imag * imag;
if (real2 + imag2 > convergenceLimit) {
return 255 - 4 * (i % 64);
}
imag = -2.0f * real * imag + c_imag;
real = real2 - imag2 + c_real;
}
return 0;
}
+5
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@@ -0,0 +1,5 @@
#include <complex.h>
#include <stddef.h>
#include <math.h>
#include <sys/types.h>
void tricorn_V4(float complex start, size_t width, ssize_t height, float res, unsigned n, _Bool color, unsigned char* img);