306 lines
8.0 KiB
C
306 lines
8.0 KiB
C
#include <stdlib.h>
|
|
#include <stdio.h>
|
|
#include <stdint.h>
|
|
#include <raylib.h>
|
|
#include <raymath.h>
|
|
#include <limits.h>
|
|
#include <complex.h>
|
|
|
|
#define WINDOW_SIZE_X 1600
|
|
#define WINDOW_SIZE_Y 800
|
|
#define RES_X 1600
|
|
#define RES_Y 800
|
|
#define DEFAULT_CENTER_X 0
|
|
#define DEFAULT_CENTER_Y 0
|
|
#define MOUSE_BUTTON 0
|
|
#define STEP_SIZE .1
|
|
#define ZOOM_SIZE .1
|
|
|
|
|
|
#define DECIMAL_LOC 28
|
|
#define DOUBLE_SCALER (1 << DECIMAL_LOC)
|
|
#define DOUBLE_TO_FIXED(val) (int32_t)((val) * DOUBLE_SCALER)
|
|
#define FIXED_MULTIPLY(x,y) ((((uint64_t)(x))*(y)) >> DECIMAL_LOC)
|
|
#define FIXED_TO_DOUBLE(val) ((val) / (double)DOUBLE_SCALER)
|
|
|
|
#define INFTY 2
|
|
#define INFTY_SQR INFTY * INFTY
|
|
#define ITERS 255
|
|
#define INFTY_SQR_FIXED DOUBLE_TO_FIXED(INFTY_SQR)
|
|
|
|
#define SHIP
|
|
//#undef SHIP
|
|
|
|
#ifdef SHIP
|
|
Color get_color(int i) {
|
|
if(i == ITERS) return (Color){0, 0, 0, 255};
|
|
if(i == 0) return (Color){0, 0, 0, 255};
|
|
return (Color) {
|
|
2*(i - 128)+255,
|
|
0,
|
|
0,
|
|
255
|
|
};
|
|
}
|
|
#else
|
|
Color get_color(int i) {
|
|
// if((i == ITERS) || (i == 0)) return (Color){0, 0, 0, 255};
|
|
if(i == ITERS) return (Color){0,255,0,255};
|
|
if(i == 0) return (Color){0, 0, 0, 255};
|
|
if(i < 128) {
|
|
return (Color) {
|
|
(8*(i - 128)+255) & 0xff,
|
|
0,
|
|
(16*(i - 64)+255) & 0xff,
|
|
255
|
|
};
|
|
}
|
|
return (Color) {
|
|
0,
|
|
0,
|
|
((unsigned int)-2*(i - 128)+255) & 0xff,
|
|
255
|
|
};
|
|
}
|
|
#endif
|
|
|
|
|
|
struct camera {
|
|
double min_r, min_i, max_r, max_i;
|
|
};
|
|
|
|
struct vec2_double {
|
|
double x, y;
|
|
};
|
|
|
|
struct vec2_float {
|
|
int32_t x, y;
|
|
};
|
|
|
|
static inline int iterate(int32_t r, int32_t i) {
|
|
int32_t z_i = 0;
|
|
int32_t z_r = 0;
|
|
int32_t z_r_2, z_i_2, zn_r, zn_i;
|
|
for(int it = 0; it < ITERS; it++) {
|
|
z_r_2 = FIXED_MULTIPLY(z_r, z_r);
|
|
z_i_2 = FIXED_MULTIPLY(z_i, z_i);
|
|
|
|
zn_r = z_r_2 - z_i_2 + r;
|
|
|
|
#ifdef SHIP
|
|
zn_i = abs(FIXED_MULTIPLY((DOUBLE_TO_FIXED(2)), (FIXED_MULTIPLY(z_r, z_i)))) + i;
|
|
#else
|
|
zn_i = (FIXED_MULTIPLY((DOUBLE_TO_FIXED(2)), (FIXED_MULTIPLY(z_r, z_i)))) + i;
|
|
#endif
|
|
|
|
z_i = zn_i;
|
|
z_r = zn_r;
|
|
|
|
if(z_i_2 + z_r_2 > INFTY_SQR_FIXED) return it;
|
|
}
|
|
return ITERS;
|
|
}
|
|
|
|
//blllluuuuurg, matracies and vectors in raylib are floats and we need doubles
|
|
void shift_cam(struct camera *cam, double step_r, double step_i) {
|
|
double i_offset = (cam->max_i - cam->min_i) * step_i;
|
|
double r_offset = (cam->max_r - cam->min_r) * step_r;
|
|
cam->min_i += i_offset;
|
|
cam->max_i += i_offset;
|
|
cam->min_r += r_offset;
|
|
cam->max_r += r_offset;
|
|
}
|
|
|
|
void zoom_cam(struct camera *cam, double zoom) {
|
|
double i_scale = (cam->max_i - cam->min_i) * zoom;
|
|
double r_scale = (cam->max_r - cam->min_r) * zoom;
|
|
cam->min_i += i_scale;
|
|
cam->max_i -= i_scale;
|
|
cam->min_r += r_scale;
|
|
cam->max_r -= r_scale;
|
|
}
|
|
|
|
enum DIRECTIONS {
|
|
N, NE, E, SE, S, SW, W, NW
|
|
};
|
|
|
|
typedef struct {
|
|
double x; double y;
|
|
} coordinate;
|
|
|
|
//we can inline these if needed
|
|
|
|
inline bool bitarray_check(uint8_t *array, size_t i) {
|
|
return array[i/8] & (1 << (i%8));
|
|
}
|
|
|
|
inline void bitarray_set(uint8_t *array, size_t i) {
|
|
array[i/8] |= (1 << (i%8));
|
|
}
|
|
|
|
/**
|
|
inline coordinate get_neighbor_coord(coordinate from_coord, int direction, coordinate step) {
|
|
if((direction == NW) && (direction < E)) from_coord.x += ;
|
|
if((direction > N) && (direction < S)) from_coord += 1;
|
|
if((direction > E) && (direction < W)) from_coord += RES_X;
|
|
if(direction > S) from_coord -= 1;
|
|
return from_coord;
|
|
}
|
|
**/
|
|
|
|
|
|
size_t get_neighbor_index(size_t from_pixel, int direction) {
|
|
//canidate for optimization; lots of branches. maybe inline
|
|
if((direction == NW) && (direction < E)) from_pixel -= RES_X;
|
|
if((direction > N) && (direction < S)) from_pixel += 1;
|
|
if((direction > E) && (direction < W)) from_pixel += RES_X;
|
|
if(direction > S) from_pixel -= 1;
|
|
return from_pixel;
|
|
}
|
|
|
|
|
|
bool bitarray_check(uint8_t *array, size_t i);
|
|
void bitarray_set(uint8_t *array, size_t i);
|
|
#define BITARRAY_SET(array, i) ((array)[(i)/8] |= (1 << ((i) % 8)))
|
|
#define BITARRAY_CHECK(array, i) ((array)[(i)/8] & (1 << ((i) % 8)))
|
|
|
|
/**
|
|
enum CANIDATE_STATUS {
|
|
UNSOLVED = 0,
|
|
CANIDATE,
|
|
NONCANIDATE
|
|
};
|
|
**/
|
|
|
|
unsigned int mandelbrot_bordertrace(struct camera *cam, Color *pixels) {
|
|
//these lookup tables r cheap cuz on the stm32f1, 1 memory read is 1 instruction
|
|
const size_t neighbor_index_accl[8] = {-RES_X, -RES_X + 1, 1, RES_X + 1, RES_X, RES_X - 1, -1, -RES_X - 1};
|
|
int32_t scale_i = DOUBLE_TO_FIXED((cam->max_i - cam->min_i) / (double)RES_Y);
|
|
int32_t scale_r = DOUBLE_TO_FIXED((cam->max_r - cam->min_r) / (double)RES_X);
|
|
int32_t c_i = DOUBLE_TO_FIXED(cam->max_i);
|
|
int32_t c_r;
|
|
unsigned int total_iters = 0;
|
|
size_t on_pixel = 0;
|
|
uint8_t border[(160*80)/8] = {0};
|
|
//for keeping track of border only. will organize later
|
|
uint8_t set[(160*80)/8] = {0};
|
|
uint8_t unset[(160*80)/8] = {0};
|
|
for(int y = 0; y < RES_Y; y++) {
|
|
c_r = DOUBLE_TO_FIXED(cam->min_r);
|
|
for(int x = 0; x < RES_X; x++) {
|
|
int i = iterate(c_r, c_i);
|
|
total_iters += i;
|
|
pixels[((y * RES_X) + x)] = get_color(i);
|
|
|
|
//this is where it all begins
|
|
if(i == ITERS) {
|
|
int current_border_pixel = on_pixel;
|
|
uint8_t visited_border[(160*80)/8] = {0};
|
|
int filled_neighbors = 0;
|
|
//unroll and manually get_neighbor if this is too slow
|
|
for(int nei_dir = 0; nei_dir < 8; nei_dir++) {
|
|
size_t nei_i = current_border_pixel + neighbor_index_accl[nei_dir];
|
|
if(bitarray_check(set, nei_i)) {
|
|
filled_neighbors++;
|
|
continue;
|
|
}
|
|
if(bitarray_check(unset, nei_i)) continue;
|
|
|
|
}
|
|
//if c_d == 7 go back
|
|
}
|
|
c_r += scale_r;
|
|
}
|
|
on_pixel++;
|
|
c_i -= scale_i;
|
|
}
|
|
return total_iters;
|
|
}
|
|
|
|
unsigned int mandelbrot_unoptimized(struct camera *cam, Color *pixels) {
|
|
int32_t scale_i = DOUBLE_TO_FIXED((cam->max_i - cam->min_i) / (double)RES_Y);
|
|
int32_t scale_r = DOUBLE_TO_FIXED((cam->max_r - cam->min_r) / (double)RES_X);
|
|
int32_t c_i = DOUBLE_TO_FIXED(cam->max_i);
|
|
int32_t c_r;
|
|
unsigned int total_iters = 0;
|
|
for(int y = 0; y < RES_Y; y++) {
|
|
c_r = DOUBLE_TO_FIXED(cam->min_r);
|
|
for(int x = 0; x < RES_X; x++) {
|
|
int i = iterate(c_r, c_i);
|
|
total_iters += i;
|
|
pixels[((y * RES_X) + x)] = get_color(i);
|
|
c_r += scale_r;
|
|
}
|
|
c_i -= scale_i;
|
|
}
|
|
return total_iters;
|
|
}
|
|
|
|
void test() {
|
|
uint8_t bitarray[(160*80)/8] = {0};
|
|
int test_i = 9;
|
|
BITARRAY_SET(bitarray, test_i);
|
|
printf("%s\n", BITARRAY_CHECK(bitarray, 9) ? "true" : "false");
|
|
}
|
|
|
|
int main() {
|
|
test();
|
|
return 0;
|
|
Color *pixels = malloc(RES_X * RES_Y * sizeof(Color));
|
|
struct camera cam = {
|
|
.min_r = -1,
|
|
.max_r = 1,
|
|
// .min_i = -1,
|
|
// .max_i = 1
|
|
};
|
|
cam.min_i = ((double)RES_Y / RES_X) * cam.min_r;
|
|
cam.max_i = ((double)RES_Y / RES_X) * cam.max_r;
|
|
InitWindow(WINDOW_SIZE_X, WINDOW_SIZE_Y, "mandelbrot fixed point test");
|
|
|
|
Image img = GenImageColor(RES_X, RES_Y, BLUE);
|
|
Texture tex = LoadTextureFromImage(img);
|
|
UnloadImage(img);
|
|
|
|
SetTargetFPS(10);
|
|
|
|
|
|
while(!WindowShouldClose()) {
|
|
switch(GetKeyPressed()) {
|
|
case KEY_UP:
|
|
shift_cam(&cam, 0, STEP_SIZE);
|
|
break;
|
|
case KEY_DOWN:
|
|
shift_cam(&cam, 0, -STEP_SIZE);
|
|
break;
|
|
case KEY_RIGHT:
|
|
shift_cam(&cam, STEP_SIZE, 0);
|
|
break;
|
|
case KEY_LEFT:
|
|
shift_cam(&cam, -STEP_SIZE, 0);
|
|
break;
|
|
case KEY_W:
|
|
zoom_cam(&cam, ZOOM_SIZE);
|
|
break;
|
|
case KEY_S:
|
|
zoom_cam(&cam, -ZOOM_SIZE);
|
|
break;
|
|
default:
|
|
BeginDrawing();
|
|
EndDrawing();
|
|
continue;
|
|
break;
|
|
}
|
|
printf("(%.21f, %.21f) - (%.21f, %.21f)\n", cam.min_r, cam.min_i, cam.max_r, cam.max_i);
|
|
|
|
printf("Unoptimized: %u iterations\n", mandelbrot_unoptimized(&cam, pixels));
|
|
//printf("Border tracing: %u iterations\n", mandelbrot_unoptimized(cam, pixels);
|
|
|
|
BeginDrawing();
|
|
UpdateTexture(tex, pixels);
|
|
DrawTextureEx(tex, (Vector2){0,0}, 0, (float)GetRenderWidth()/RES_X, WHITE);
|
|
EndDrawing();
|
|
}
|
|
|
|
return 0;
|
|
}
|