I have polygon given by the points sequence
I need to apply follow rules:
- angles must be 180,90,45 degrees;
- if lines parallel then distanse beetwen the lines greater then minValue;
- orientation of polygon is horizontal and vertical.
(If the closest to a specific problem, then I find the contours of objects in OpenCV, then they should be nice to draw)
I need to do somthing like this:

What you are asking seems non trivial, and not so well defined. More context is required.
I would try two approaches:
overlay a square grid on the polygon and keep the squares that are sufficiently filled.
skelettonize the shape (http://en.wikipedia.org/wiki/Topological_skeleton), cleanup, and break the skeleton into mostly horizontal/vertical segments; then replace these segments by truly horizontal/vertical strokes.