Symbol line direction in curved polygon

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This topic contains 0 replies, has 1 voice, and was last updated by  Barry Kelly 4 years ago.

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    Barry Kelly

    I am modifying a GS hedge object to make it a little more useful for myself.
    I want to add a ‘grass’ symbol line type to the perimeter in plan to make it look a little more hedgy.
    This works fine when the perimeter is closed on a curved hedge.
    But as soon as I use the masking code to turn off the line for one edge the line on the inside curve inverts for some reason.
    There is no problem at all for a straight hedge – only when the polygon has a curve it seems.

    Here is the code used for the polygon.

    rad = 1.000
    breit = 0.500
    wink = 90
    end_1_swch = 1
    end_2_swch = 0	 !!change to 1 to close polygon
    poly2_b 7,1+2+4,gs_fill_pen,gs_back_pen,
    	rad, 0,3001

    Reversing the polygon doesn’t help either.

    add2 1.5, 0
    poly2_b 7,1+2+4,gs_fill_pen,gs_back_pen,
    	rad, 0,1
    del 1

    Even using ARC2 won’t help as you can’t reverse the direction of the line and can’t use a negative radius.

    Is this a bug (and if so can it be fixed)?
    Any ideas for a solution that doesn’t involve creating a new symbol line type that is reversed in the y direction and then using two polygons with various edges hidden or not?

    I am guessing that the positive y portion of a symbol line will always project towards the centre of an arc unless in a closed polygon with visible edges in which the direction can be reversed depending on the order of node scripting.



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