Java 计算哪个绘制的圆最接近另一个圆
我想得到距离我的特殊圆最小的圆的x和y。我用计时器创建了25个圆圈，需要检查场上绘制的每个圆圈。我已经拥有的是：Java 计算哪个绘制的圆最接近另一个圆,java,android,position,distance,geometry,Java,Android,Position,Distance,Geometry,我想得到距离我的特殊圆最小的圆的x和y。我用计时器创建了25个圆圈，需要检查场上绘制的每个圆圈。我已经拥有的是： protected void onDraw (android.graphics.Canvas canvas){ //If arrow-button was clicked, do ... get the circle with the lowest distance to viking circle if (buttonClicked == true) {
protected void onDraw (android.graphics.Canvas canvas){
//If arrow-button was clicked, do ... get the circle with the lowest distance to viking circle
if (buttonClicked == true) {
//distance of the current circle from the viking
int tempCircleDistance = 0;
//the minimum distance we have found so far in our loop
int minCircleDistance = 0;
//index of the min circle we have found so far
int indexOfNearest=0;
for(int i = 0; i<circlesOnTheField; i++)
{
//help me Phytagoras
tempCircleDistance = (int) (Math.sqrt((viking.getX() - circles.get(i).getX())*
(viking.getX() - circles.get(i).getX())+
(viking.getY() - circles.get(i).getY())*
(viking.getY() - circles.get(i).getY()))-
(viking.getR() + circles.get(i).getR()));
//first cycle or did we find the nearest circle? If so update our variables
if(i==0||tempCircleDistance<minCircleDistance)
{
indexOfNearest=i;
minCircleDistance=tempCircleDistance;
}
}
if(circles.get(indexOfNearest).getIsDrawn() == true) {
//draw the line with the given index of the nearest circle
//At this point, nearest circle is calculated and we draw a line from viking to that circle
canvas.drawLine(viking.getX(), viking.getY(),
circles.get(indexOfNearest).getX(),
circles.get(indexOfNearest).getY(),
pgoal);
//Here we delete the circle and increase our variable frags for one more killed opponent.
deleteCircle(circles.get(indexOfNearest));
circlesOnTheField--;
frags++;
buttonClicked = false;
}
}
//END
//This is where the circles are drawn
for(int k = 0; k<circlesOnTheField; k++) {
canvas.drawCircle(circles.get(k).getX(), circles.get(k).getY(), circles.get(k).getR(), p3);
circles.get(k).setIsDrawn(true);
}
}
addCircle（）addCircle（）moveCircle（）publicstaticvoidmovecircle（）{
对于（inti=0；iIm，假设getR（）给出半径？！
然后尝试以下操作，而不是for循环：
//distance of the current circle from the viking
int tempCircleDistance = 0;
//the minimum distance we have found so far in our loop
int minCircleDistance = 0;
//index of the min circle we have found so far
int indexOfNearest=0;
for(int i = 0; i<circlesOnTheField; i++)
{
//help me Phytagoras
tempCircleDistance = (int) (Math.sqrt((viking.getX() - circles[i].getX())*
(viking.getX() - circles[i].getX())+
(viking.getY() - circles[i].getY())*
(viking.getY() - circles[i].getY()))-
(viking.getR() + circles[i].getR()));
//first cycle or did we find the nearest circle? If so update our variables
if(i==0||tempCircleDistance<minCircleDistance)
{
indexOfNearest=i;
minCircleDistance=tempCircleDistance;
}
}
//draw the line with the given index of the nearest circle
canvas.drawLine(viking.getX(), viking.getY(),
circles[indexOfNearest].getX(),
circles[indexOfNearest].getY(),
pgoal);
//当前圆与viking的距离
int tempCircleDistance=0；
//到目前为止，我们在环路中找到的最小距离
int minCircleDistance=0；
//到目前为止我们已经找到的最小圆的索引
int indexOfNearest=0；
对于if（i>=1）{…
部分中的（int i=0；iI），为什么只检查ifcircledistance[i]
比上一个小，而不是比所有其他距离都小？如果从圆到您的特殊圆的距离小于任何其他圆到特殊圆的距离，则该圆应仅分配给箭头圆
。我认为如果从第一个圆开始，只看一眼就可以了在下一个，因为它应该总是一个较小的值，对吗？考虑如下：画一个特殊的圆。然后画第二个圆，叫它A。假设它与特殊圆的距离是5（根据距离的一些定义）。现在画第三个和第四个圆，分别是B和C。在画B之后，检查它与a的距离。让我们假设B与特殊圆的距离为7，因此a仍然是最近的。在画C之后，我们检查它与B的距离，让我们假设C的距离为6，然后<代码>距离（C）<距离（B）
。但是仍然要对照A检查，否则它会错误地导致C是最接近的。哇，你是个魔术师：D！这真的很有效！哈哈！我只是在想一个新主意。我可以使用直线作为向量，并以预定义的速度移动位图（如果可能的话，旋转）使用这个向量指向最近的圆？只是想法！非常感谢！！！可能是的。你有起点和终点，你有长度，没有什么可以反对它。我假设像一个炮弹攻击最近的圆或什么？！对！像一把投掷斧！继续尝试吧！用所需的变量创建一个向量类，然后尝试utOk在尝试之前，我对删除最近的圆有一个问题。只要我不使用删除方法，我的viking circle就会得到一条到最近圆的连接线（他们总是向下移动）。然后，当我把删除放进去时，这条线会非常快地画成两到三个圆圈，有时会在两秒钟后画出一个圆圈。看看我编辑的代码。谢谢
public static void addCircle() {
if(circlesOnTheField >= 25) {
circlesOnTheField = 25;
}
else{
circlesOnTheField++;
}
}
public static void moveCircle() {
for(int i=0; i<circlesOnTheField; i++) {
//Move circles downwards
circles.get(i).setY(circles.get(i).getY()+5);
//Check if the circle collides with the viking
if(detectCollision(viking, circles.get(i))) {
deleteCircle(circles.get(i));
circles.get(i).setIsDrawn(false);
life--;
}
//Check if the circle intersects the goal line and recreate it if yes
if(intersects(circles.get(i).getX(), circles.get(i).getY(), circles.get(i).getR(), 0, 750, 500, 760)) {
deleteCircle(circles.get(i));
circles.get(i).setIsDrawn(false);
circlesInGoal++;
}
}
}
public static void createNewCircleOnCanvas() {
//Collision Detection
circles.clear();
int createdCircles = 0;
outer: while (createdCircles < 25) {
int randomX = r.nextInt(500);
int randomY = r.nextInt(300);
candidate = new Circle(randomX, randomY, 33, "Circle"+createdCircles, false);
inner: for (int z = 0; z<createdCircles;z++) {
//If new created circle collides with any already created circle or viking, continue with outer
if (detectCollision(candidate, circles.get(z))) continue outer;
}
circles.add(candidate);
createdCircles++;
}
//distance of the current circle from the viking
int tempCircleDistance = 0;
//the minimum distance we have found so far in our loop
int minCircleDistance = 0;
//index of the min circle we have found so far
int indexOfNearest=0;
for(int i = 0; i<circlesOnTheField; i++)
{
//help me Phytagoras
tempCircleDistance = (int) (Math.sqrt((viking.getX() - circles[i].getX())*
(viking.getX() - circles[i].getX())+
(viking.getY() - circles[i].getY())*
(viking.getY() - circles[i].getY()))-
(viking.getR() + circles[i].getR()));
//first cycle or did we find the nearest circle? If so update our variables
if(i==0||tempCircleDistance<minCircleDistance)
{
indexOfNearest=i;
minCircleDistance=tempCircleDistance;
}
}
//draw the line with the given index of the nearest circle
canvas.drawLine(viking.getX(), viking.getY(),
circles[indexOfNearest].getX(),
circles[indexOfNearest].getY(),
pgoal);