呵呵昨天花了一個圓，今天想畫個太極圖，我知道沒啥技術含量，但是挺有意思的，希望各位看官不要鄙視我不務正業，畫完此圖，不再做這些事情。
先展示下畫出來的影像的情況，因為不支援pgm格式的影像，所以我用的 QQ截圖：
今天，二話不說上程式碼。同時再次致謝Banu前輩。
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#include <stdio.h> #include <stdlib.h> #include <string.h> #include <math.h> typedef struct { size_t width; size_t height; unsigned char *data; } Image; static Image * image_new (size_t width, size_t height) { Image *image; image = malloc (sizeof *image); image->width = width; image->height = height; image->data = malloc (width * height); return image; } static void image_free (Image *image) { free (image->data); free (image); } static void image_fill (Image *image, unsigned char value) { memset (image->data, value, image->width * image->height); } /** * image_set_pixel: * * Sets a pixel passed in signed (x, y) coordinates, where (0,0) is at * the center of the image. **/ static void image_set_pixel (Image *image, ssize_t x, ssize_t y, unsigned char value) { size_t tx, ty; unsigned char *p; tx = (image->width / 2) + x; ty = (image->height / 2) + y; p = image->data + (ty * image->width) + tx; *p = value; } static void image_save (const Image *image, const char *filename) { FILE *out; out = fopen (filename, "wb"); if (!out) return; fprintf (out, "P5\n"); fprintf (out, "%zu %zu\n", image->width, image->height); fprintf (out, "255\n"); fwrite (image->data, 1, image->width * image->height, out); fclose (out); } static void draw_Taijitu(Image *image,int radius,int value) { int x,y; int rlimit ,llimit; int radius_2 = radius*radius; for(y = -radius;y<radius;y++) for(x= -radius;x<radius;x++) if(x*x+y*y <= radius_2) image_set_pixel(image,x,y,0xff); for(y = -radius;y<0;y++) for(x = 0;x<radius;x++) if((x*x)+(y*y) <= radius_2) image_set_pixel(image,x,y,value); for(y = -radius;y<0;y++) for(x = -(int)sqrt((double)(-radius*y-y*y));x<0;x++) image_set_pixel(image,x,y,value); for(y = 0;y<radius;y++) { llimit = (int)sqrt((double)(radius*y - y*y)); rlimit = (int)sqrt((double)(radius_2 - y*y)); for(x = llimit;x<rlimit;x++) image_set_pixel(image,x,y,value); } for(y = 2*radius/6;y<4*radius/6;y++) { rlimit =(int) sqrt((double)(radius*y-y*y-2*radius_2/9)); llimit = -rlimit; for(x = llimit;x<rlimit;x++) image_set_pixel(image,x,y,value); } for(y = -4*radius/6;y<-2*radius/6;y++) { rlimit = sqrt(-radius*y-y*y-2*radius_2/9); llimit = -rlimit; for(x = llimit;x<rlimit;x++) image_set_pixel(image,x,y,0xff); } return ; } int main (int argc, char *argv[]) { Image *image; image = image_new (800, 800); image_fill (image, 0xaa); draw_Taijitu (image, 300, 0); image_save (image, "taiji_6.pgm"); image_free (image); return 0; } |