79 lines
1.9 KiB
C
79 lines
1.9 KiB
C
// Compile using:
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// cc -W -Wall --pedantic --std=c99 -Ofast sandpile-video.c -lpng -lm -o sandpile-video
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// The run it to produce png files:
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// sandpile-video 2000
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// Then use ffmpeg to convert to a video
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// ffmpeg -pattern_type glob -i '*.png' out.mp4
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#include <stdlib.h>
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#include <stdbool.h>
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#include <string.h>
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#include <inttypes.h>
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#include <stdio.h>
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#include <math.h>
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#include "common.c"
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void apply_gravity(int width, int **terrain)
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{
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bool did_something;
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int div;
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while (1) {
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did_something = false;
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for (int x = 0; x < width; x++) {
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for (int y = 0; y < width; y++) {
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if (terrain[x][y] >= 4) {
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did_something = true;
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div = terrain[x][y] / 4;
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terrain[x][y] = terrain[x][y] % 4;
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terrain[x - 1][y] += div;
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terrain[x + 1][y] += div;
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terrain[x][y + 1] += div;
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terrain[x][y - 1] += div;
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}
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}
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}
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if (!did_something)
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return;
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}
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}
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int **sandpile_new(int width)
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{
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int **terrain = calloc(width, sizeof(int*));
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int *data = calloc(width * width, sizeof(int));
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for (int i = 0; i < width; i++) {
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terrain[i] = data + i * width;
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}
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return terrain;
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}
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#define STEP 100
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int main(int argc, char **argv)
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{
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args args = {0};
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if (parse_args(argc, argv, &args))
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return EXIT_FAILURE;
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int width = sandpile_width(args.height);
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int **terrain = sandpile_new(width);
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char imgname[255] = {0};
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for (int i = 0; i < args.height; i += STEP) {
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terrain[width / 2][width / 2] += STEP;
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apply_gravity(width, terrain);
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sprintf(imgname, "sandpile-%i-%010i.png", args.height, i);
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if (save_terrain(width, terrain, imgname) == 0)
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printf("%i/%i saved\n", i, args.height);
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else
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printf("Can't save terrain\n");
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}
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return EXIT_SUCCESS;
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}
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