This bit of code doesn't seem to work.
for(var b = 0; b < wallPoints.length-1; b++)
{
wallPoints[b].xPos = wallPoints[b]-1;
}
function Point(x,y)
{
this.xPos = x;
this.yPos = y;
}
wallPoints is an array of Points
The code doesn't return any errors, it just makes all my code stop executing. This is my first time using JavaScript, so this is probably a very stupid mistake.
What are you trying to do -- shift each point by one in the x axis? You need to reference the property on the right hand side of the assignment as well.
for(var b = 0; b < wallPoints.length; b++)
{
wallPoints[b].xPos = wallPoints[b].xPos - 1;
}
or do you want to propagate the x axis from one point to another
for(var b = 1; b < wallPoints.length; b++)
{
wallPoints[b].xPos = wallPoints[b-1].xPos;
}
In the latter case, you'll need to figure out what to do with the first point. Note the change in the termination condition (and start condition in the second case).
EDIT: Here's my test code:
<html>
<head>
<title>Point</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>
<script type="text/javascript">
$(function() {
var wallPoints = new Array();
wallPoints[0] = new Point(0,10);
wallPoints[1] = new Point(600,10);
wallPoints[2] = new Point(650,10);
var content = $('#content');
content.append('<h2>Before</h2>');
for(var b = 0; b < wallPoints.length; b++)
{
content.append('<p> x = ' + wallPoints[b].xPos + ', y = ' + wallPoints[b].yPos + '</p>' );
wallPoints[b].xPos = wallPoints[b].xPos-1;
}
content.append('<h2>After</h2>');
for(var b = 0; b < wallPoints.length; b++)
{
content.append('<p> x = ' + wallPoints[b].xPos + ', y = ' + wallPoints[b].yPos + '</p>' );
}
function Point(x,y)
{
this.xPos = x;
this.yPos = y;
}
});
</script>
</head>
<body>
<div id="content">
</div>
</body>
</html>
You're assigning an X variable equal to a point. Not an option:
for(var b = 0; b < wallPoints.length-1; b++)
{
wallPoints[b].xPos = wallPoints[b]-1;
}
instead try this:
for(var b = 0; b < wallPoints.length-1; b++)
{
wallPoints[b].xPos = wallPoints[b].xPos - 1;
}
wallPoints[b].xPos = wallPoints[b]-1;wallPointsplease.var wallPoints = [new Point(0,10), new Point(600,10), new Point(650,10)];