当我运行这段代码并返回错误距离时,不会生成新的随机数。不断产生相同的随机数,从而使我陷入无限循环。有谁知道为什么会这样?谢谢你的期待!
private void setRandomVerticies()
{
//generate 200 triangles
this.randomVerticies = new LinkedList<TGVertex>();
random.setSeed(System.currentTimeMillis());
short x = 5000, y = 5000;
int specT = 0;
int vert = 0;
int triangleCount = 0;
int rx = 0, ry = 0;
int sameAxis = 0;
TGVertex check = new TGVertex(x,y);
for (int i = 1; i <= 600; i++)
{
for (;;)
{
rx = random.nextInt();
ry = random.nextInt();
System.out.println("generate a new random number please");
if(i == 1) break;
if (specT == 1) //approximately 50 triangles will have 2 vertices against the edge
{
if (sameAxis == 0 || sameAxis == 1) { rx = 0;
}else if (sameAxis == 2 || sameAxis == 3) { ry = 0;
}else if (sameAxis == 4 || sameAxis == 5) { rx = tImage.getWidth()-1;
}else if (sameAxis == 6 || sameAxis == 7) { ry = tImage.getHeight()-1; }
check = new TGVertex(rx, ry);
if (!randomVerticies.contains(check))
{
if (vert == 2 && distance(check, randomVerticies.get(i-2)))
{
sameAxis++;
if (sameAxis == 8) sameAxis = 0;
break; //breaks while loop if new vertex is chosen
}
else if (vert == 1)
{
sameAxis++;
if (sameAxis == 8) sameAxis = 0;
break; //breaks while loop if new vertex is chosen
}
}
}
rx = (short)(rx & 0x1FF);
ry = (short)(rx & 0x19D);
check = new TGVertex(rx, ry);
System.out.println("rx = " + rx + " ry = " + ry);
System.out.println("check = " + check.getX() + ", " + check.getY());
System.out.println("randomVert = " + randomVerticies.get(i-2).getX() + ", " + randomVerticies.get(i-2).getY());
if (!randomVerticies.contains(check) && distance(check, randomVerticies.get(i-2))) break; //breaks while loop if new vertex is chosen
}
String sliceX = Integer.toHexString(this.width()-1);
String sliceY = Integer.toHexString(this.height()-1);
int sX = (int) Integer.parseInt(sliceX, util.Global.HEX);
int sY = (int) Integer.parseInt(sliceY, util.Global.HEX);
x = (short) (rx & sX);
y = (short) (ry & sY);
//System.out.println("("+x+", "+y+")");
randomVerticies.add( new TGVertex(x, y) );
if (i % 3 == 0) triangleCount++;
if (triangleCount == 2 && vert < 3 )
{
specT = 1;
vert++;
}
if (vert == 3)
{
specT = 0;
vert = 0;
triangleCount = 0;
}
}
}
这是输出,你可以看到randomVert永远不会改变值。
rx = 196 ry = 132
check = 196, 132
randomVert = 225, 392
generate a new random number please
rx = 383 ry = 285
check = 383, 285
randomVert = 225, 392
generate a new random number please
rx = 328 ry = 264
check = 328, 264
randomVert = 225, 392
generate a new random number please
rx = 102 ry = 4
check = 102, 4
randomVert = 225, 392
generate a new random number please
rx = 197 ry = 133
check = 197, 133
randomVert = 225, 392
generate a new random number please
rx = 62 ry = 28
check = 62, 28
randomVert = 225, 392
generate a new random number please
rx = 295 ry = 261
check = 295, 261
randomVert = 225, 392
generate a new random number please
rx = 142 ry = 140
check = 142, 140
randomVert = 225, 392
generate a new random number please
rx = 261 ry = 261
check = 261, 261
randomVert = 225, 392
答案 0 :(得分:1)
您正在循环中创建Random
的背对背新实例。只需创建一个(在循环外部!),并在需要新值时询问它是否为随机数。想想它就像挖井一样 - 你每次想要喝一杯水都不会挖新井,你就挖一口井,然后根据需要再去喝多少饮料。