On Aug 21, 4:58=A0pm, "jbwest" <jbw...@[EMAIL PROTECTED]
> wrote:
> "uuilly" <willy.li...@[EMAIL PROTECTED]
> wrote in message
>
> news:b204512e-7fb7-4fdc-9d46-369db9277154@[EMAIL PROTECTED]
> On Aug 21, 9:11 am, "jbwest" <jbw...@[EMAIL PROTECTED]
> wrote:
>
>
>
> > <willy.p...@[EMAIL PROTECTED]
> wrote in message
>
>
>news:c45bd917-ce46-4f04-82e7-4cf6508e6e15@[EMAIL PROTECTED]
> > On Aug 20, 5:40 pm, "jbwest" <jbw...@[EMAIL PROTECTED]
> wrote:
>
> > [...]
>
> > > Gosh, it's been a while... Is it a closure problem? Do you need to
ad=
d a
> > > last point =3D 1st in the input data to close up the polygon ?
>
> > > jbw
> > >I've tried w/ and w/o a last=3D=3Dfirst. It's funny, it fixes some of
=
the
> > >counties and breaks just as many others. Any other thoughts? My next
> > > move is to write my own tessellation algorithm.
>
> > That's definitely a closure, off-by-one or last-triangle logic
problem.
> > I've
> > never had problems with the much-maligned tesselator with very complex
> > geometries. Surely you can just trace what's being emitted and see why
=
the
> > last triangle isn't being created (or has the wrong winding ?).
>
> > jbw
> >I think I get closure, first =3D=3D last, but what is an: "Off by one"
o=
r
> >"last triangle logic problem"? =A0Thanks for the advice btw.
>
> Your sample data doesn't even invoke Combine on my Linux glu Tesselator
> sample app. Just a combination of tri-strips and tri-fans, resulting in
a
> rectangle. One or the other of those types of BEGIN appears to be
> implemented wrong in your app. Otherwise, does this note apply to you ?
>
> "Notes
> It is a common error to use a local variable for location or data and
sto=
re
> values into it as part of a loop. For example: for (i =3D 0; i <
NVERTICE=
S;
> ++i) {
> =A0 GLdouble data[3];
> =A0 data[0] =3D vertex[i][0];
> =A0 data[1] =3D vertex[i][1];
> =A0 data[2] =3D vertex[i][2];
> =A0 gluTessVertex(tobj, data, data);
> =A0 }
>
> This doesn't work. Because the pointers specified by location and data
mi=
ght
> not be dereferenced until gluTessEndPolygon is executed, all the vertex
> coordinates but the very last set could be overwritten before
tessellatio=
n
> begins.
>
> Two common symptoms of this problem are consists of a single point (when
=
a
> local variable is used for data) and a GLU_TESS_NEED_COMBINE_CALLBACK
err=
or
> (when a local variable is used for location."
>
> jbw
Wow. Can you paste all your gluCallbacks here?
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