模仿自然界的雪花的程序-mimic natural snow procedures.zip

#define DEGREE 6 /* 递归层次 */ #define SQRT3 1.732 /* 向量旋转参数， A(x+iy)逆时针旋转六十度后为 B (x+iy)*( 1/2+ ^/3i/2) */ #include <graphics.h> void snowpart(int x1,int y1,int x5,int y5,int degree) /* 递归画图 */ { int x2,y2,x3,y3,x4,y4; /*一条线段拆分成四条*/ int deltX, deltY; if (degree==0) /* 递归终点 */ { line(x1,y1,x5,y5); return; } deltX=x5-x1; /* 线段: ______ */ deltY=y5-y1; /* 拆分: __/\__ */ /* 1 234 5 */ x2=x1+deltX/3; y2=y1+deltY/3; x4=x2+deltX/3; y4=y2+deltY/3; x3=x2+(deltX+(int)(SQRT3*deltY))/6; y3=y2+(deltY-(int)(SQRT3*deltX))/6; snowpart(x1,y1,x2,y2,degree-1); snowpart(x2,y2,x3,y3,degree-1); snowpart(x3,y3,x4,y4,degree-1); snowpart(x4,y4,x5,y5,degree-1); } main() { int x1=100 ,y1=350; int x2=200 ,y2=177; int x3=300 ,y3=350; int i=0; int driver=DETECT, mode=0; initgraph(&driver,&mode,""); setfillstyle(SOLID_FILL,WHITE); while(i<DEGREE) { sleep(1); cleardevice(); snowpart(x1,y1,x2,y2,i); snowpart(x2,y2,x3,y3,i); snowpart(x3,y3,x1,y1,i); i++; } floodfill((x1+x2+x3)/3,(y1+y2+y3)/3,WHITE); getch(); }