## Symbol line direction in curved polygon

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• #2599
Barry Kelly
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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,end_1_swch,
rad+breit,0,1,
0,0,900,
(rad+breit)*cos(wink),(rad+breit)*sin(wink),3000+end_2_swch,
rad*cos(wink),rad*sin(wink),1,
0,0,900,
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,
0,0,900,
rad*cos(wink),rad*sin(wink),3000+end_2_swch,
(rad+breit)*cos(wink),(rad+breit)*sin(wink),1,
0,0,900,
rad+breit,0,3000+end_1_swch,
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.

Barry.

###### Attachments:

Versions 6.5 to 22
Dell XPS- i7-6700 @ 3.4Ghz, 16GB ram, GeForce GTX 960 (2GB), Windows 10
Dell Precision M6800 - i7 4700MQ @ 2.40GHz, 16GB RAM, AMD FirePro M6100 (2GB), Windows 7 64bit

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