title: html canvas resolution issue with overlaying boxes
body: <p>I have noticed issues with drawing one box over another. As requested, here is the code, but in greater detail</p>
  
  <pre><code>function draw(x,y,w,h,c){
   ctx.fillStyle=c;
   ctx.strokeStyle=c;
   ctx.lineWidth=1;
   ctx.globalAlpha=1.0;
   ctx.fillRect(x,y,w,h);
  }
  
  function Rectangle(x,y,w,h,c){
   this.x=x;
   this.y=y;
   this.w=w;
   this.h=h;
   this.c=c;
   this.draw=draw;
  
   this.onMouseEnter=function(){
    this.c='rgb(0,0,0)';   //black
    this.draw();
   }
  
  this.onMouseLeave=function(){
   this.c='rgb(255,255,255)';   //white
   this.draw();
   }
  }
  box=new Rectangle(10,10,110,110,'rgb(255,255,255)');  //black box at
  </code></pre>
  
  <p>At rest the box is white, but on hover, it turns black. However, there is still a white border. I am pretty sure this is not a calculation error on my part as I am changing the color, not the dimensions. I have also noticed this problem occurring in most of my other onHover functions.</p>
  
  <p>Why does HTML have these problems with drawing over other objects.</p>
  
  <p>Thanks</p>