Removing Points within a form (pipe)

Hey all,

I am working on a pixilation project to design a high-rise building. The objective is to remove a group of targeted pixels by points, lines and boxes. I have succeeded at doing this, however; the distance from the line will be the same for all of the lines.

In order to have each line determine the amount of pixels deselected I was thinking piping the line would work best. This does not however work the same as the box witch deselects all of the pixels within the box. It deselects the pixels within a distance of the surface of the pipe.

Could you please help me with deselecting all of the pixels inside the pip as well.

Thank you for your time