diff options
Diffstat (limited to 'graphics.c')
| -rw-r--r-- | graphics.c | 67 |
1 files changed, 51 insertions, 16 deletions
@@ -6,35 +6,48 @@ #define WINDOW_TITLE "Mandelbrot" #define WINDOW_X 20 #define WINDOW_Y 20 -#define WINDOW_W 300 -#define WINDOW_H 300 -#define REFRESH_RATE 3 +#define WINDOW_W 500 +#define WINDOW_H 500 +#define REFRESH_RATE 1 #define MOVE_SIZE 0.1 #define ZOOM_SIZE 0.1 -#define BRIGHTNESS_LO 0 -#define BRIGHTNESS_HI 10 +#define RED_MASK 0xFF0000 +#define GREEN_MASK 0x00FF00 +#define BLUE_MASK 0x0000FF +#define RED(c) ((c & RED_MASK) >> (8 * 2)) +#define GREEN(c) ((c & GREEN_MASK) >> 8) +#define BLUE(c) (c & BLUE_MASK) +#define MERGE_RGB(r, g, b) ((r) << (8 * 2) | (g) << 8 | (b)) +#define PALETTE_START 0x334455 +#define PALETTE_END 0xFFFFFF +#define SET_DRAW_COLOR_RGB(renderer, c) ( \ + SDL_SetRenderDrawColor(renderer, RED(c), GREEN(c), BLUE(c), SDL_ALPHA_OPAQUE)) +#define IN_SET_COLOR 0x000000 static void update(GState *state); static void event_handler(GState *state); +static Color *create_palette(Color start, Color end); static void destroy_state(GState *state); static void error_exit_state(GState *state, const char *msg); static void error_exit(const char *msg); GState *graphics_init(void) { - GState *state = (GState*)malloc(sizeof(GState)); - if (state == NULL) - return NULL; if (SDL_Init(SDL_INIT_VIDEO) < 0) error_exit("unable to init SDL"); + GState *state = (GState*)malloc(sizeof(GState)); + if (state == NULL) + error_exit("state allocation failed"); state->window = SDL_CreateWindow(WINDOW_TITLE, WINDOW_X, WINDOW_Y, WINDOW_W, WINDOW_H, 0); if (state->window == NULL) - error_exit("unable to create window"); + error_exit_state(state, "unable to create window"); state->renderer = SDL_CreateRenderer(state->window, -1, 0); if (state->renderer == NULL) error_exit_state(state, "unable to create renderer"); + if ((state->palette = create_palette(PALETTE_START, PALETTE_END)) == NULL) + error_exit_state(state, "unable to create color palette"); state->running = true; state->window_w = WINDOW_W; state->window_h = WINDOW_H; @@ -63,8 +76,8 @@ void graphics_run(GState *state) static void update(GState *state) { - double a, b, brightness; - SDL_SetRenderDrawColor(state->renderer, 0, 0, 0, SDL_ALPHA_OPAQUE); + double a, b; + SET_DRAW_COLOR_RGB(state->renderer, IN_SET_COLOR); SDL_RenderClear(state->renderer); for (int x = 0; x < state->window_w; x++) { @@ -76,10 +89,7 @@ static void update(GState *state) int steps = mandelbrot_in_set(mapped_z); if (steps == -1) continue; - brightness = map_range(steps, state->real_lo, state->real_hi, - BRIGHTNESS_LO, BRIGHTNESS_HI); - SDL_SetRenderDrawColor(state->renderer, brightness, brightness, - brightness, SDL_ALPHA_OPAQUE); + SET_DRAW_COLOR_RGB(state->renderer, state->palette[steps]); SDL_RenderDrawPoint(state->renderer, x, y); } } @@ -96,42 +106,67 @@ static void event_handler(GState *state) case SDL_QUIT: state->running = false; break; - case SDL_KEYUP: + case SDL_KEYDOWN: switch (e.key.keysym.sym) { case SDLK_UP: + case SDLK_k: state->imag_lo -= MOVE_SIZE; state->imag_hi -= MOVE_SIZE; break; case SDLK_DOWN: + case SDLK_j: state->imag_lo += MOVE_SIZE; state->imag_hi += MOVE_SIZE; break; case SDLK_LEFT: + case SDLK_h: state->real_lo -= MOVE_SIZE; state->real_hi -= MOVE_SIZE; break; case SDLK_RIGHT: + case SDLK_l: state->real_lo += MOVE_SIZE; state->real_hi += MOVE_SIZE; break; + case SDLK_PLUS: case SDLK_p: state->real_lo += ZOOM_SIZE; state->real_hi -= ZOOM_SIZE; state->imag_lo += ZOOM_SIZE; state->imag_hi -= ZOOM_SIZE; break; + case SDLK_MINUS: case SDLK_m: state->real_lo -= ZOOM_SIZE; state->real_hi += ZOOM_SIZE; state->imag_lo -= ZOOM_SIZE; state->imag_hi += ZOOM_SIZE; break; + case SDLK_q: + state->running = false; + break; } } } } +static Color *create_palette(Color start, Color end) +{ + Color red_step = abs(RED(end) - RED(start)) / MAX_ITERATION; + Color green_step = abs(GREEN(end) - GREEN(start)) / MAX_ITERATION; + Color blue_step = abs(BLUE(end) - BLUE(start)) / MAX_ITERATION; + + Color *palette = (Color*)malloc(sizeof(Color) * MAX_ITERATION); + if (palette == NULL) + return NULL; + for (int i = 0; i < MAX_ITERATION; i++) + palette[i] = MERGE_RGB(i * red_step + RED(start), + i * green_step + GREEN(start), + i * blue_step + BLUE(start)); + return palette; +} + static void destroy_state(GState *state) { if (state == NULL) |