I need to draw polygons with lines at boundary to give good appearence. lines drawn first by "PrimitiveType.lines" then polygons drawn by "PrimitiveType.Triangles" and enabling depth test + DepthFunction.Less. I have two problem. 1.when zoom out, the polygons becomes small as requied while lines has fixed line width that cover all drawing at zoom out (zoom by increse orthognal view size). I need to make lines disappear or very small width when zoom out (polygons are faraway) 2.Lines behind a polygon are not displayed as enable depthfunction to be less. however lines that are too close benhind polygons appear with hidden pattern. I need to make all not displayed if behind polygon.