javascript逻辑返回奇怪的结果(javascript logic returning strange results)

 我有一个网格，我正在尝试将光标编程到，网格中有一个中心点，我试图让光标只能从该中心点移动x个方块，这里是我的代码 
 
var makecursor = function (axis, operation) {
    oppositeAxis = axis === 'y' ? 'x' : 'y';

    // app.cursor contains the x and y coordinates of the cursor
    app.cursor[axis] = 

    // calcualte the difference between the current cursor location and the origin
    Math.abs( app.cursor[axis] - origin[axis] ) + 

   // calculate the difference between the opposite axis and
   // the origin and add it to the previous calculation
    Math.abs( app.cursor[oppositAxis] - origin[oppositeAxis] ) 

  // add the operation to be performed ( movement of cursor, 1 or -1 )
  + operation 

  // if the sum of the x, y and current operation are greater then the allowed
  // movement, then make "app.cursor[axis]" equal to itself (dont move) , 
  // otherwise make "app.cursor[axis]" equal to itself plus the operation ( move )

> origin.movement ? app.cursor[axis] : app.cursor[axis] + operation;
}
 
 “操作”是1或-1，用于定向 
 
 “origin.movement”是您可以移动光标的原点的平方数。 
 
 我希望/期望的行为是从我的网格上的一个正方形，你只能移动“origin.movement”变量中指定的正方形。 但是当我打印出结果时，它返回了奇怪的数字，并且它没有正确计算位置，即原点应该为零，而是取而代之的是一个或两个，这取决于之前的运动，还有许多其他我没有的异常能够理解。 任何帮助这个问题将不胜感激，谢谢！ 

I have a grid that I am trying to program a cursor onto, there is a central point in the grid and I am trying to make the cursor only be able to move x amount of squares from that central point, here is the code I have
 
var makecursor = function (axis, operation) {
    oppositeAxis = axis === 'y' ? 'x' : 'y';

    // app.cursor contains the x and y coordinates of the cursor
    app.cursor[axis] = 

    // calcualte the difference between the current cursor location and the origin
    Math.abs( app.cursor[axis] - origin[axis] ) + 

   // calculate the difference between the opposite axis and
   // the origin and add it to the previous calculation
    Math.abs( app.cursor[oppositAxis] - origin[oppositeAxis] ) 

  // add the operation to be performed ( movement of cursor, 1 or -1 )
  + operation 

  // if the sum of the x, y and current operation are greater then the allowed
  // movement, then make "app.cursor[axis]" equal to itself (dont move) , 
  // otherwise make "app.cursor[axis]" equal to itself plus the operation ( move )

> origin.movement ? app.cursor[axis] : app.cursor[axis] + operation;
}
 
"operation" is either 1 or -1, for directional 
 
"origin.movement" is the number of squares from the origin you can move the cursor.
 
my hopes / expected behavior is that from a square on my grid, you can only move as many squares are specified in "origin.movement" variable. but it is returning strange numbers when i print out the results, and it doesn't calculate the locations correctly, i.e. origin should be zero, but is instead one, or two, depending on previous movements, many other anomalies that I haven't been able to understand. any help with this problem would be appreciated, thanks!

原文：https://stackoverflow.com/questions/29861966