🚀 go-pugleaf

I am writing code that produces a cross-section of various layers. To differentiate the layers I am trying to use various patterns such as: hatching with straight lines, diagonal lines, cross-hatching, circles, etc.. However, I am finding it difficult to create just evenly spaced vertical and horizontal lines. The following is a sample code that (I think should) produces a evenly spaced cross-hatching pattern, or grid type of pattern:

<< /PatternType 1 % Tiling pattern
        /PaintType 1 % Colored
        /TilingType 3
        /BBox [50 0 100 100]
        /XStep 10
        /YStep 10
        /PaintProc
        {
                pop % pop pattern dictionary
                %0.0 0.0 0.0 setrgbcolor
                72.0 72.0 scale 0 setlinewidth
                0 1 50 {0 moveto 0 11 rlineto} for
                0 1 50 {0 exch moveto 8 0 rlineto} for
                stroke
        } bind 

      > % End prototype pattern dictionary




This works on a standard page ok. However, when I try it on my drawing the cross-hatching comes out not evenly spaced. Any ideas? Also, does anybody know a good informational place to get postscript code in languatelevel 3 for producing such patterns. I still need to come up with circles and other various types of standard patterns. Thanks.