Drawing An X Shape On A HTML5 Canvas And Checking For Collisions With A Border

I am working on a maze game in HTML 5. Here is the function which I use to draw an 'X' on the canvas (using the touchpad, the user will navigate the X through the labyrinth). dim =

Solution 1:

Wow, writing the question made it clear:

var imgd = ctx.getImageData(checkx - xdim, checky - xdim, 16, 16);

Ty guys