Set visualization

Loop throught each pixel and color it black if its in the set,
white otherwise.
This is eavily inspired by the coding train video on the subject.
(https://www.youtube.com/watch?v=6z7GQewK-Ks)

5 files changed, 55 insertions, 21 deletions

diff --git a/Makefile b/Makefile
index 03be06e..dc19c48 100644
--- a/Makefile
+++ b/Makefile
@@ -4,7 +4,7 @@ CCFLAGS = -Wall -Wextra
 LDFLAGS = -lm $(shell sdl2-config --libs --cflags)
 
 HEADER = header.h
-SRC = main.c graphics.c mandelbrot.c
+SRC = main.c graphics.c mandelbrot.c helper.c
 OBJ = $(SRC:.c=.o)
 
 RM = rm -f
diff --git a/graphics.c b/graphics.c
index e9e12ff..1e7470f 100644
--- a/graphics.c
+++ b/graphics.c
@@ -4,6 +4,7 @@
 #define WINDOW_X 20
 #define WINDOW_Y 20
 
+static void update(GState *state);
 static void event_handler(GState *state);
 static void destroy_state(GState *state);
 static void error_exit_state(GState *state, const char *msg);
@@ -17,7 +18,7 @@ GState *graphics_init(GConf *conf)
     if (SDL_Init(SDL_INIT_VIDEO) < 0)
         error_exit("unable to init SDL");
     state->window = SDL_CreateWindow(WINDOW_TITLE, WINDOW_X, WINDOW_Y,
-                                     conf->window_width, conf->window_height, 0);
+                                     WINDOW_W, WINDOW_H, 0);
     if (state->window == NULL)
         error_exit("unable to create window");
     state->renderer = SDL_CreateRenderer(state->window, -1, 0);
@@ -38,9 +39,28 @@ void graphics_run(GState *state)
     while (state->running)
     {
         event_handler(state);
+        update(state);
+        SDL_Delay(3);
+    }
+}
 
-        SDL_Delay(10);
+static void update(GState *state)
+{
+    SDL_SetRenderDrawColor(state->renderer, 155, 155, 155, SDL_ALPHA_OPAQUE);
+    SDL_RenderClear(state->renderer);
+    for (int x = 0; x < WINDOW_W; x++)
+    {
+        for (int y = 0; y < WINDOW_H; y++)
+        {
+            if (mandelbrot_in_set(map_range((double)x, 0, WINDOW_W, LO, HI)
+                                  + map_range((double)y, 0, WINDOW_H, LO, HI) * I))
+            {
+                SDL_SetRenderDrawColor(state->renderer, 0, 0, 0, SDL_ALPHA_OPAQUE);
+                SDL_RenderDrawPoint(state->renderer, x, y);
+            }
+        }
     }
+    SDL_RenderPresent(state->renderer);
 }
 
 static void event_handler(GState *state)
diff --git a/header.h b/header.h
index 855cff3..97e3de6 100644
--- a/header.h
+++ b/header.h
@@ -5,6 +5,18 @@
 # include <complex.h>
 # include <SDL2/SDL.h>
 
+# define WINDOW_W 500
+# define WINDOW_H 500
+
+# define LO -1.5
+# define HI 1.5
+# define AXIS_DIV 46.0
+# define AXIS_STEP ((HI - LO) / AXIS_DIV)
+
+# define MAX_ITERATION 50
+# define _INFINITY 15
+
+
 typedef struct
 {
     SDL_Window *window;
@@ -27,4 +39,7 @@ GState *graphics_init(GConf *conf);
 void graphics_quit(GState *state);
 void graphics_run(GState *state);
 
+// helper.c
+double map_range(double x, double src_lo, double src_hi, double dest_lo, double dest_hi);
+
 #endif
diff --git a/helper.c b/helper.c
new file mode 100644
index 0000000..9920c5d
--- /dev/null
+++ b/helper.c
@@ -0,0 +1,10 @@
+#include <math.h>
+#include "header.h"
+
+double map_range(double x, double src_lo, double src_hi, double dest_lo, double dest_hi)
+{
+    double src_len = fabs(src_hi - src_lo);
+    double dest_len = fabs(dest_hi - dest_lo);
+
+    return (x - src_lo) / src_len * dest_len + dest_lo;
+}
diff --git a/mandelbrot.c b/mandelbrot.c
index 053ce70..c5f5148 100644
--- a/mandelbrot.c
+++ b/mandelbrot.c
@@ -1,28 +1,11 @@
 #include <stdio.h>
 #include <math.h>
 #include <complex.h>
-
-#define LO -1.7
-#define HI 1.7
-#define AXIS_DIV 46.0
-#define AXIS_STEP ((HI - LO) / AXIS_DIV)
-
-#define MAX_ITERATION 1000
-#define _INFINITY 1000
+#include "header.h"
 
 #define IN_CHAR '*'
 #define OUT_CHAR ' '
 
-/*
-#define SQUARE(x) (pow((x), 2))
-#define SQUARE_CML(z) (SQUARE(creal(z)) - SQUARE(cimag(z)) + 2 * creal(z) * cimag(z) * I)
-
-double magnitude(double complex z)
-{
-    return sqrt(SQUARE(creal(z)) + SQUARE(cimag(z)));
-}
-*/
-
 double mandelbrot_in_set(double complex c)
 {
     int i;
@@ -52,3 +35,9 @@ void mandelbrot_print(void)
     }
 }
 
+/*
+#define SQUARE(x) (pow((x), 2))
+#define SQUARE_CML(z) (SQUARE(creal(z)) - SQUARE(cimag(z)) + 2 * creal(z) * cimag(z) * I)
+
+double magnitude(double complex z) { return sqrt(SQUARE(creal(z)) + SQUARE(cimag(z))); }
+*/