From 4e332fdfdccd7c617b0eba00e1da9886227eb485 Mon Sep 17 00:00:00 2001
From: JP Appel <jeanpierre.appel01@gmail.com>
Date: Sat, 20 Apr 2024 02:25:24 -0400
Subject: fixed mandel & multibrot sets, added cli options

---
 src/mandelbrot.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 68 insertions(+), 11 deletions(-)

(limited to 'src')

diff --git a/src/mandelbrot.c b/src/mandelbrot.c
index 63db30d..f8e65f7 100644
--- a/src/mandelbrot.c
+++ b/src/mandelbrot.c
@@ -2,16 +2,18 @@
 #include <stddef.h>
 #include <stdint.h>
 #include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
 
-#include "plotting.h"
+#include "grids.h"
 
 /*
  * Computes the number of iterations it takes for a point z0 to diverge
  * if the return value is equal to max_iterations, the point lies within the mandelbrot set
- * This is an implementation the esacpe algorithm
+ * This is an implementation the escape algorithm
  */
-size_t mandelbrot(double complex z0, size_t max_iterations) {
-  double complex z = 0.0 + 0.0*I;
+size_t mandelbrot(const double complex z0, const size_t max_iterations) {
+  double complex z = z0;
   size_t iteration = 0;
 
   while (cabs(z) <= 2 && iteration < max_iterations) {
@@ -27,8 +29,8 @@ size_t mandelbrot(double complex z0, size_t max_iterations) {
  * This is implementation closely matches mandelbrot
  * Note, only positive integer powers are supported
  */
-size_t multibrot(double complex z0, size_t max_iterations, uintmax_t d){
-    double complex z = 0.0 + 0.0*I;
+size_t multibrot(const double complex z0, const size_t max_iterations, const uintmax_t d){
+    double complex z = z0;
     double complex ztemp;
     size_t iteration = 0;
     while(cabs(z) <= 2 && iteration < max_iterations){
@@ -42,10 +44,65 @@ size_t multibrot(double complex z0, size_t max_iterations, uintmax_t d){
     return iteration;
 }
 
+/*
+ * Converts a grid point into an complex number
+ */
+double complex lattice_to_complex(const size_t index, const size_t x_res, const size_t y_res) {
+    const double x_min = -2.0;
+    const double x_max = 2.0;
+    const double y_min = -2.0;
+    const double y_max = 2.0;
+
+    const double x_step = (x_max - x_min) / (double)x_res;
+    const double y_step = (y_max - y_min) / (double)y_res;
+
+    const size_t x_index = index % x_res;
+    const size_t y_index = index / x_res;
+
+    const double x = x_min + x_index * x_step;
+    const double y = y_min + y_index * y_step;
+
+    return x + y * I;
+}
+
+
+int main(const int argc, char *argv[]) {
+    //default values
+    size_t iterations = 1000;
+    size_t x_res = 100;
+    size_t y_res = 100;
 
-int main(const int argc, const char *argv[]) {
-    double complex z = 1.0 + 0.0*I;
-    size_t result = mandelbrot(z, 1000);
-    printf("Input: %f+%fI\n", creal(z), cimag(z));
-    printf("result: %zu\n", result);
+    //parse command line arguments
+    int opt;
+    while((opt =getopt(argc, argv, "i:x:y:")) != -1){
+        switch(opt){
+            case 'i':
+                iterations = strtoull(optarg, NULL, 10);
+                break;
+            case 'x':
+                x_res = strtoull(optarg, NULL, 10);
+                break;
+            case 'y':
+                y_res = strtoull(optarg, NULL, 10);
+                break;
+            default:
+                fprintf(stderr, "Usage: %s [-i iterations] [-x x_res] [-y y_res]\n", argv[0]);
+                return 1;
+        }
+    }
+
+
+    grid_t* grid = create_grid(x_res, y_res);
+    if(!grid) return 1;
+
+
+    const size_t size = grid->size;
+    size_t* data = grid->data;
+    for(size_t i = 0; i < size;i++){
+        data[i] = multibrot(lattice_to_complex(i, x_res, y_res), iterations, 3);
+    }
+
+    for(size_t i = 0; i < size; i++){
+        printf("%zu%s", data[i], (i % x_res == x_res - 1) ? "\n" : "\t");
+    }
 }
-- 
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