参考
- 《C和C++游戏趣味编程》
见缝插圆
随机生成的圆互不相交且尽量填满画布，按空格键可以切换不同的绘制模式
每次增加一个随机圆
设定圆的个数circleNum=100，定义3个数组用于存储所有圆的圆心坐标、半径，然后每隔100毫秒，添加一个随机圆并绘制
#include <graphics.h>
#include <conio.h>
#include <stdio.h>
#include <time.h>
int main()
{
int width = 600;
int height = 600;
initgraph(width, height);
setbkcolor(RGB(255, 255, 255));
cleardevice();
srand(time(0));
int xArray[100];
int yArray[100];
int rArray[100];
int rmin = 8;
int rmax = 50;
int circleNum = 0;
float x, y, r;
while (circleNum < 100)
{
x = rand() % width;
y = rand() % height;
r = rand() % (rmax - rmin + 1) + rmin;
xArray[circleNum] = x;
yArray[circleNum] = y;
rArray[circleNum] = r;
circleNum++;
setlinecolor(RGB(0, 0, 0));
setfillcolor(RGB(255, 255, 0));
fillcircle(x, y, r);
Sleep(100);
}
_getch();
closegraph();
return 0;
}
新圆不和已有圆相交
每次随机生成一个新圆后，首先与所有已经生成的圆比较，如果和任何一个圆相交，则重新生成一个新圆；如果新圆和所有已生成的圆都不相交，则循环结束，将此圆添加到数组中
设置标志变量isNewCircleOK=0，当新圆满足不和已有圆相交时，isNewCircle==1
isNewCircleOK = 0;
while (isNewCircleOK == 0)
{
x = rand() % width;
y = rand() % height;
r = rand() % (rmax - rmin + 1) + rmin;
for (i = 0; i < circleNum; i++)
{
float dist2 = (xArray[i] - x) * (xArray[i] - x) + (yArray[i] - y) * (yArray[i] - y);
float r2 = (rArray[i] + r) * (rArray[i] + r);
if (dist2 < r2)
{
break;
}
}
if (i == circleNum)
{
isNewCircleOK = 1;
}
}
新圆半径最大化
如果生成的圆和之前已生成的圆都不相交，则不断增大新圆的半径，直到找到第一个与该圆相切的圆，或达到rmax为止
#include <graphics.h>
#include <conio.h>
#include <stdio.h>
#include <time.h>
#include <math.h>
// 求解两个点之间的距离
float Dist2Points(float x1, float y1, float x2, float y2)
{
float result;
result = sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
return result;
}
// 判断两个圆是否相交
int isTwoCirclesIntersect(float x1, float y1, float r1, float x2, float y2, float r2)
{
if (Dist2Points(x1, y1, x2, y2) < r1 + r2)
{
return 1;
}
return 0;
}
int main()
{
int width = 600;
int height = 600;
initgraph(width, height);
setbkcolor(RGB(255, 255, 255));
cleardevice();
srand(time(0));
int xArray[1000];
int yArray[1000];
int rArray[1000];
int rmin = 8;
int rmax = 50;
int circleNum = 0;
float x, y, r;
int isNewCircleOK;
int i, j;
while (circleNum < 1000)
{
isNewCircleOK = 0;
while (isNewCircleOK == 0)
{
x = rand() % width;
y = rand() % height;
r = rmin;
for (i = 0; i < circleNum; i++)
{
if (isTwoCirclesIntersect(xArray[i], yArray[i], rArray[i], x, y, r))
{
break;
}
}
if (i == circleNum)
{
isNewCircleOK = 1; // 新生成的圆和已有圆都不相交
}
}
isNewCircleOK = 0; // 继续设为不OK，下面让这个新圆的半径最大
while (isNewCircleOK == 0 && r < rmax)
{
r++;
for (j = 0; j < circleNum; j++)
{
if (isTwoCirclesIntersect(xArray[j], yArray[j], rArray[j], x, y, r))
{
isNewCircleOK = 1;
break;
}
}
}
xArray[circleNum] = x;
yArray[circleNum] = y;
rArray[circleNum] = r;
circleNum++;
setlinecolor(RGB(0, 0, 0));
setfillcolor(RGB(255, 255, 0));
fillcircle(x, y, r);
Sleep(10);
}
_getch();
closegraph();
return 0;
}
封装多种绘制效果
// 填充黄色圆绘制
void DrawCircles1(float x, float y, float r)
{
setlinecolor(RGB(0, 0, 0));
setfillcolor(RGB(255, 255, 0));
fillcircle(x, y, r);
}
// 填充随机颜色圆绘制
void DrawCircles2(float x, float y, float r)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.6, 0.8);
setlinecolor(RGB(255, 255, 255));
setfillcolor(color);
fillcircle(x, y, r);
}
// 填充随机颜色同心圆绘制
void DrawCircles3(float x, float y, float r)
{
while (r > 0)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.6, 0.8);
setlinecolor(RGB(255, 255, 255));
setfillcolor(color);
fillcircle(x, y, r);
r -= 5;
}
}
// 随机颜色同心圆线条绘制
void DrawCircles4(float x, float y, float r)
{
while (r > 0)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.9, 0.8);
setlinecolor(color);
circle(x, y, r);
r -= 5;
}
}
按键互动
当按下空格键后，将circleNum设为0，相当于清除所有已有的圆；将drawMode加1，从而切换为下一种绘图模式
#include <graphics.h>
#include <conio.h>
#include <stdio.h>
#include <time.h>
#include <math.h>
// 求解两个点之间的距离
float Dist2Points(float x1, float y1, float x2, float y2)
{
float result;
result = sqrt((x1 - x2) * (x1 - x2) + (y1 - y2) * (y1 - y2));
return result;
}
// 判断两个圆是否相交
int isTwoCirclesIntersect(float x1, float y1, float r1, float x2, float y2, float r2)
{
if (Dist2Points(x1, y1, x2, y2) < r1 + r2)
{
return 1;
}
return 0;
}
// 填充黄色圆绘制
void DrawCircles1(float x, float y, float r)
{
setlinecolor(RGB(0, 0, 0));
setfillcolor(RGB(255, 255, 0));
fillcircle(x, y, r);
}
// 填充随机颜色圆绘制
void DrawCircles2(float x, float y, float r)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.6, 0.8);
setlinecolor(RGB(255, 255, 255));
setfillcolor(color);
fillcircle(x, y, r);
}
// 填充随机颜色同心圆绘制
void DrawCircles3(float x, float y, float r)
{
while (r > 0)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.6, 0.8);
setlinecolor(RGB(255, 255, 255));
setfillcolor(color);
fillcircle(x, y, r);
r -= 5;
}
}
// 随机颜色同心圆线条绘制
void DrawCircles4(float x, float y, float r)
{
while (r > 0)
{
float h = rand() % 360;
COLORREF color = HSVtoRGB(h, 0.9, 0.8);
setlinecolor(color);
circle(x, y, r);
r -= 5;
}
}
int main()
{
int width = 600;
int height = 600;
initgraph(width, height);
setbkcolor(RGB(255, 255, 255));
cleardevice();
srand(time(0));
int xArray[1000];
int yArray[1000];
int rArray[1000];
int rmin = 8;
int rmax = 50;
int circleNum = 0;
float x, y, r;
int isNewCircleOK;
int i, j;
int drawMode = 3;
while (circleNum < 1000)
{
isNewCircleOK = 0;
while (isNewCircleOK == 0)
{
if (_kbhit())
{
char input = _getch();
if (input == ' ')
{
circleNum = 0;
cleardevice();
drawMode += 1;
if (drawMode > 4)
{
drawMode = 1;
}
}
}
x = rand() % width;
y = rand() % height;
r = rmin;
for (i = 0; i < circleNum; i++)
{
if (isTwoCirclesIntersect(xArray[i], yArray[i], rArray[i], x, y, r))
{
break;
}
}
if (i == circleNum)
{
isNewCircleOK = 1; // 新生成的圆和已有圆都不相交
}
}
isNewCircleOK = 0; // 继续设为不OK，下面让这个新圆的半径最大
while (isNewCircleOK == 0 && r < rmax)
{
r++;
for (j = 0; j < circleNum; j++)
{
if (isTwoCirclesIntersect(xArray[j], yArray[j], rArray[j], x, y, r))
{
isNewCircleOK = 1;
break;
}
}
}
xArray[circleNum] = x;
yArray[circleNum] = y;
rArray[circleNum] = r;
circleNum++;
if (drawMode == 1)
{
DrawCircles1(x, y, r);
}
if (drawMode == 2)
{
DrawCircles2(x, y, r);
}
if (drawMode == 3)
{
DrawCircles3(x, y, r);
}
if (drawMode == 4)
{
DrawCircles4(x, y, r);
}
Sleep(10);
}
_getch();
closegraph();
return 0;
}
