【转帖】hatch problem
 

hatch problem
hatch problem
hi.
i have a problem with a loop hatch .
this is the loop definition according to autocad:
"a loop must be simple, closed, and continuous, intersecting itself only at its endpoints.
furthermore, its start point and end point must coincide. when defining the hatch
boundary, the application must ensure that the loops and edges are well defined and
structured. if the boundary contains two or more loops, they must be organized into
a nested structure in which the external loop is constructed first, then followed by
all its internal loops in nested order. if there is more than one external loop, repeat
the process. autocad provides limited validation of the hatch boundary in
order to maintain api efficiency and performance."
i send you an example of a loop hatch which doesn´t keep this definition.
if i open this example with autocad 2004 and i save it, then i have
a loop without problems.
how can i solve this problem?
attached files
hi gabriel,
this is a stupid geometric of a lwpolyline for use as a hatchboundary.
i think, a technical planer doesn't construct this. try to close the lwpolyline and you get the lwpolyline example for a outerloop.
if you want to hatch some drawing entities, you must think about the result you wish.
regards
___________
ralph
gabriel,
actually in autocad only solid hatch always has closed loops. if it's a hatch (not solid fill) loops can be not closed, self intersecting etc.. when hatch is rendered points of intersection of hatch line and all edges are found and odd/even rule is used to draw hatch lines. it's impossible to get closed loops from hatch in such cases.
see also
in the file attached where is a block insertion with hatch round-trip xdata. while loading files of minor versions dd processes this xdata and turns block insertion into hatch object. autocad leaves this block insertion as is. after the file is saved to ac2004 version dd does not convert block insertion into hatch because file version is the latest.
sergey slezkin