• TechNotes
• Alignment of adjoining roof edge lines

The following screen capture shows the problem users face when drawing the contour of adjoining Roofs using line types other than Solid or Continuous Lines. This also applies to any Polygon Type Elements on the Floor Plan, the contour line types of that can be set.

As you can see the edges of the two Roof polygons that are closest to each other do not coincide in their pattern. The result of this is if they adjoin, the result will be an almost continuous line which does not look good graphically in the Project.

This is a problem of direction of the lines within the polygon. When the contour polygon is drawn, it is either drawn clockwise around its geometric center or counter-clockwise. If one draws it manually, one can of course control this direction. When it is generated automatically, it is a matter of chance which direction it will get created.

The reason they are not correctly aligned is because the direction of the two line segments of the two Roof polygons is not the same. Also, the line types are started from the first point from where the contour polygon was originally started to be drawn. So from this point of view, it counts whether the contour polygon was started from its lower left, upper right or any other of its corners.

So here is what to do: draw the left Polygon starting from its upper right corner and draw it clockwise. Then draw the right polygon starting from its upper left corner, drawing it counter-clockwise. In case of adjoining edges, the starting point and the direction of the first edge of the two polygons will be the same and this is the key of creating the edges the line type patterns of which will coincide.

• Category2dDrawing