Created
March 17, 2020 00:06
-
-
Save lukakostic/92dae027a219a086a30054291b460ce3 to your computer and use it in GitHub Desktop.
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| /* | |
| Use these commands to render img.ppm: | |
| w & h: 4000 4000 | |
| 2 -.5 0 .3 | |
| 1 | |
| */ | |
| #include<stdio.h> | |
| #include<stdlib.h> | |
| #include<vector> | |
| using namespace std; | |
| struct Complex{ double x,y; }; | |
| struct Color{ unsigned char r,g,b; }; | |
| //e is ^ , t is * , p is + | |
| //z^2 + c (Mandelbrot set) | |
| #define Ze2pC \ | |
| zt.x = z.x * z.x - z.y * z.y + c.x;\ | |
| zt.y = 2.0 * z.x * z.y + c.y;\ | |
| z = zt; | |
| //Global settings | |
| static unsigned int height = 1000, width = 1500; | |
| static vector<Color> pixels; | |
| //view x and y, zoom | |
| static double vx = -.5, vy = 0, zoom = 1.0; | |
| static double limit = 4.0; //2^2 | |
| static unsigned int maxIter = 200; | |
| static Complex startPoint = Complex{0,0}; | |
| void SaveImage(){ | |
| printf("Saving image... "); | |
| FILE *fp = fopen("img.ppm", "wb"); | |
| (void) fprintf(fp, "P6\n%u %u\n255\n", width, height); | |
| fwrite(&pixels[0], sizeof(vector<Color>::value_type), width*height, fp); | |
| fclose(fp); | |
| printf(" Saved\n"); | |
| } | |
| void Render(){ | |
| printf("Rendering... "); | |
| Color white = Color{(unsigned char)255,(unsigned char)255,(unsigned char)255}; | |
| Color black = Color{(unsigned char)0,(unsigned char)0,(unsigned char)0}; | |
| for (int i = 0; i < (width*height); i++) | |
| { | |
| //Center & Scale pixels to view -1.0 to 1.0 for 1000x1000 | |
| //get 2d index - offset to make centered, div by 2.0(turn -.5,.5 to -1,1)/1000.0(scale 1kx1k to -1,1) (500) | |
| double x = ((i % width) - (width / 2.0)) / 500.0; | |
| double y = ((i / width) - (height / 2.0)) / 500.0; | |
| //Move and zoom view | |
| x = x * zoom + vx; | |
| y = y * zoom + vy; | |
| Complex c = Complex {x, y}; | |
| Complex z = startPoint; | |
| Complex zt = z; //z temp | |
| for (size_t j = 0; j < maxIter; j++) | |
| { | |
| Ze2pC | |
| } | |
| if((z.x*z.x+z.y*z.y) < limit){ | |
| pixels[i] = white; | |
| }else{ | |
| pixels[i] = black; | |
| } | |
| } | |
| printf(" Rendered\n"); | |
| SaveImage(); | |
| } | |
| bool ReadCmd(){ | |
| int cmd = 0; | |
| printf("Enter a command (0 for help):\n"); | |
| scanf("%d",&cmd); | |
| if(cmd == 0){ | |
| printf("1 - render & save, 2 - set [vx vy zoom], 3 - set iterations [maxIter], 4 - set iteration start point, 5 - set [width height], 6 - quit\n"); | |
| }else if(cmd == 1){ | |
| Render(); | |
| }else if(cmd == 2){ | |
| scanf("%lf %lf %lf",&vx,&vy,&zoom); | |
| }else if(cmd == 3){ | |
| scanf("%u",&maxIter); | |
| }else if(cmd == 4){ | |
| scanf("%lf %lf",&startPoint.x,&startPoint.y); | |
| }else if(cmd == 5){ | |
| scanf("%u %u",&width,&height); | |
| pixels.clear(); | |
| pixels = vector<Color>(width * height); | |
| }else if(cmd == 6) | |
| return false; | |
| return true; | |
| } | |
| int main(int argc, char* argv[]) { | |
| int w,h; | |
| printf("width height: "); | |
| scanf("%u %u",&w,&h); | |
| width = w; | |
| height = h; | |
| pixels = vector<Color>(width * height); | |
| while(ReadCmd()){} | |
| return 0; | |
| } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment