#include <graphics.h> /*预定义库函数*/
void circlePoint(int x,int y)/*八分法画圆程序*/
{
circle(320+x*20,240+y*20,3)
circle(320+y*20,240+x*20,3)
circle(320-y*20,240+x*20,3)
circle(320-x*20,240+y*20,3)
circle(320-x*20,240+y*20,3)
circle(320-x*20,240-y*20,3)
circle(320-y*20,240-x*20,3)
circle(320+y*20,240-x*20,3)
circle(320+x*20,240-y*20,3)
}
void MidBresenhamcircle(int r) /* 中点Bresenham算法画圆的程序 */
{
int x,y,d
x=0y=rd=1-r /* 计算初始值 */
while(x<y)
{ circlePoint(x,y) /* 绘制点(x,y)及其在八分圆中的另外7个对称点 */
if(d<0) d+=2*x+3/* 根据误差项d的判断,决定非最大位移方向上是走还是不走 */
else
{ d+=2*(x-y)+5
y--
}
x++
delay(900000)
} /* while */
}
main()
{
int i,j,r,graphmode,graphdriver
detectgraph(&graphdriver,&graphmode)
initgraph(&graphdriver,&graphmode," ")
printf("中点Bresenhamcircle算法画圆的程序\n")/*提示信息*/
printf("注意 |r|<=11")
printf("\n输入半径值 r:")
scanf("%d",&r)
printf("按任意键显示图形...")
getch()
cleardevice()
setbkcolor(BLACK)
for(i=20i<=620i+=20) /*使用双循环画点函数画出表格中的纵坐标*/
for(j=20j<=460j++)
putpixel(i,j,2)
for(j=20j<=460j+=20) &n欢迎光临学网,收藏本篇文章 [1] [2]
$False$
bsp/*使用双循环画点函数画出表格中的横坐标*/
for(i=20i<=620i++)
putpixel(i,j,2)
outtextxy(320,245,"0")/*原点坐标*/
outtextxy(320-5*20,245,"-5")circle(320-5*20,240,2) /*横坐标值*/
outtextxy(320+5*20,245,"5")circle(320+5*20,240,2)
outtextxy(320-10*20,245,"-10")circle(320-10*20,240,2)
outtextxy(320+10*20,245,"10")circle(320+10*20,240,2)
outtextxy(320-15*20,245,"-15")circle(320-15*20,240,2)
outtextxy(320+15*20,245,"15")circle(320+15*20,240,2)
outtextxy(320,240-5*20,"-5")circle(320,240-5*20,2) /*纵坐标值*/
outtextxy(320,240+5*20,"5")circle(320,240+5*20,2)
outtextxy(320,240-10*20,"-10")circle(320,240-10*20,2)
outtextxy(320,240+10*20,"10")circle(320,240+10*20,2)
outtextxy(20,10,"The center of the circle is (0,0) ") /*坐标轴左上角显示提示信息*/
setcolor(RED)/*标记坐标轴*/
line(20,240,620,240) outtextxy(320+15*20,230,"X")
line(320,20,320,460) outtextxy(330,20,"Y")
setcolor(YELLOW)
MidBresenhamcircle(r)
setcolor(BLUE)/*绘制圆*/
circle(320,240,r*20)
setcolor(2)
getch()
closegraph()
}
#include <math.h>#include <stdio.h>#define R 10 //半径 #define X 10 //圆心x坐标 #define Y 10 //圆心Y坐标 int main(void){ int x,y int m int i for(i=Y-Ri>=1i--)
{ printf("\n")
}
for(y=Ry>=-Ry--)
{
m=2*sqrt(R*R - y*y) //横坐标的偏移量，因为字体长宽比例为2，所以要乘2
for(x=1x<X+R-mx++) //打印左半圆
{ printf(" ")
} printf("*") for(x<X+R+mx++) //打印右半圆
{ printf(" ")
} printf("*\n")
}
}
