diff options
| -rw-r--r-- | graphics.c | 15 | ||||
| -rw-r--r-- | header.h | 10 | ||||
| -rw-r--r-- | mandelbrot.c | 50 |
3 files changed, 51 insertions, 24 deletions
@@ -16,7 +16,7 @@ #define IMAG_LO(state) (state->center.y - state->imag_range / 2) #define IMAG_HI(state) (state->center.y + state->imag_range / 2) -#define IN_SET_COLOR 0x000000 +#define IN_SET_COLOR 0x050505 #define PALETTE_START 0x000022 #define PALETTE_END 0xd62f2f #define SET_DRAW_COLOR(renderer, c) ( \ @@ -24,7 +24,7 @@ static void update(GState *state); static void event_handler(GState *state); -static Color *create_palette(Color start, Color end); +/* static Color *create_palette(Color start, Color end); */ /* static void move_center(GState *state, int motion_x, int motion_y); */ static void recenter(GState *state, int x, int y); static void recenter_x(GState *state, int x); @@ -96,10 +96,13 @@ static void update(GState *state) { a = map_range((double)x, 0, state->window_w, REAL_LO(state), REAL_HI(state)); b = map_range((double)y, 0, state->window_h, IMAG_LO(state), IMAG_HI(state)); - int steps = mandelbrot_in_set(a + b * I); - if (steps == -1) + int frac_steps = mandelbrot_in_set(a, b); + if (frac_steps == -1) continue; - color = state->palette[steps]; + color = state->palette[frac_steps]; + /* color.rgb.r = 100 * frac_steps; */ + /* color.rgb.g = 100 * frac_steps; */ + /* color.rgb.b = 100 * frac_steps; */ SET_DRAW_COLOR(state->renderer, color); SDL_RenderDrawPoint(state->renderer, x, y); } @@ -180,7 +183,7 @@ static void event_handler(GState *state) } } -static Color *create_palette(Color start, Color end) + Color *create_palette(Color start, Color end) { int red_step = abs(end.rgb.r - start.rgb.r) / MAX_ITERATION; int green_step = abs(end.rgb.g - start.rgb.g) / MAX_ITERATION; @@ -10,8 +10,9 @@ # define REAL_RANGE 4.0 # define IMAG_RANGE 4.0 -# define MAX_ITERATION 20 -# define ESCAPE_VALUE 2 +# define MAX_ITERATION 35 +# define ESCAPE_RADIUS 2 +# define ESCAPE_RADIUS_SQUARED (ESCAPE_RADIUS * ESCAPE_RADIUS) typedef unsigned char Byte; typedef int ColorHexcode; @@ -49,13 +50,16 @@ typedef struct } GState; // mandelbrot.c -int mandelbrot_in_set(double _Complex c); +int mandelbrot_in_set(double a, double b); void mandelbrot_print(void); +int *mandelbrot_array(Point center, double real_range, double imag_range, + double real_len, double imag_len); // graphics.c GState *graphics_init(void); void graphics_quit(GState *state); void graphics_run(GState *state); +Color *create_palette(Color start, Color end); // helper.c double map_range(double x, double src_lo, double src_hi, double dest_lo, double dest_hi); diff --git a/mandelbrot.c b/mandelbrot.c index d44b12b..92e7a64 100644 --- a/mandelbrot.c +++ b/mandelbrot.c @@ -14,26 +14,53 @@ #define IN_CHAR '*' #define OUT_CHAR ' ' -int mandelbrot_in_set(double complex c) +int mandelbrot_in_set(double ca, double cb) { - int i; - double complex z = 0; - for (i = 0; i < MAX_ITERATION; i++) + double zr = ca; + double zi = cb; + double zr_square; + double zi_square; + for (int n = 0; n < MAX_ITERATION; n++) { - z = cpow(z, 2) + c; - if (cabs(z) > ESCAPE_VALUE) - return i; + zi_square = zi * zi; + zr_square = zr * zr; + if (zr_square + zi_square > ESCAPE_RADIUS_SQUARED) + return n; + /* return n + 5 - clog(ESCAPE_RADIUS) / log(2); */ + zi = 2 * zr * zi; + zr = zr_square - zi_square; + zi += cb; + zr += ca; } return -1; } +int *mandelbrot_array(Point center, double real_range, double imag_range, + double real_len, double imag_len) +{ + double i = center.y - imag_range / 2; + double r = center.x - real_range / 2; + int *array = malloc(sizeof(int) * imag_len * real_len); + + for (int array_i = 0; array_i < imag_len; array_i++) + { + for (int array_j = 0; array_j < real_len; array_j++) + { + array[array_i * (int)imag_len + array_j] = mandelbrot_in_set(r, i); + r += real_range / real_len; + } + i += imag_range / imag_len; + } + return array; +} + void mandelbrot_print(void) { for (double i = PRINT_IMAG_LO; i < PRINT_IMAG_HI; i += IMAG_AXIS_STEP) { for (double r = PRINT_REAL_LO; r < PRINT_REAL_HI; r += REAL_AXIS_STEP) { - if (mandelbrot_in_set(r + i * I) == -1) + if (mandelbrot_in_set(r, i) == -1) putchar(IN_CHAR); else putchar(OUT_CHAR); @@ -42,10 +69,3 @@ void mandelbrot_print(void) putchar('\n'); } } - -/* -#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))); } -*/ |