weird behavior Alex Tweedly alex at tweedly.net Mon Jul 19 19:06:54 EDT 2004
* Previous message: weird behavior * Next message: weird behavior * Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]
--snip
Not true if you add the polygon in the IDE. You can create a polygon with 3
vertices, leaving it to default to opaque. (click at 100,100 - click at
200,100 - double-click at 200,200)
The result is that two edges are drawn (i.e. NOT the third closing edge),
there is no additional (duplicate) point not added to the point list. If
you give it a fill colour, you will see that it is filled as though the
third closing edge were there - but the edge itself is not drawn.
No not correct, you didn't do the action complete (and please this is no offence). You left out following comment:
< Draw a so called open polygon and **add 2 returns for welformed-ness sake**.
Deselect the polygon and reselect it and have a look at the points: the so called open polygon is closed now, the first point is added.>
If you draw an "open" ploygon like that and if you look at the points, then it is what you called a *malformed polygon*.
If you add 2 returns to make it a *welformed polygon* and then deselect and reselect you will see the engine adds the starting point.
And yes it will be filled, in both cases if there are enclosed regions.
(I only looked at the way the engine works)
(Though the point, and the drawn edge, will be added when you do certain
edits to the polygon.)
And if you do the same thing in a script, you get the last point duplicated
for you.
>Your so called "welformed <open> polygons" are in fact <closed> ones if
>the opaque property is set.and the engine gets his way.
>Have a look at the points.
> Draw a so called open polygon and add 2 returns for welformed-ness sake.
> Deselect the polygon and reselect it and have a look at the points: the
> so called open polygon is closed now, the first point is added.
See my counter-example above :-)
btw - after creating the polygon, I deselected the polygon, saved the
stack, and quit Revolution, then restarted it - all to make sure I was not
being misled by the Property Inspector lagging the stack contents.
See above
In any case, it is not a requirement that all edges exist on an opaque
polygon. You can draw an opaque polygon with blank lines in the middle of
the point list. This results in those edges being left undrawn, and the
fill behaviour is straightforward (though hard to describe in words). It
produces a set of non-contiguous shapes; the series of edges between any
two blank lines (or the start->blank line, and blank line->end) produces a
filled shape, with an implicit edge being used in the fill but not drawn.
Some language problem. < it is not a requirement that all edges exist on an opaque polygon >
the *existence* of en edge
From the point of the viewer: if it is not drawn, it does not exist.
But from the point of view of the engine, it depends on the order of the points to draw
the polygon (or any other form) if an edge exists and if it is visible or not.
If a polygon contains a couple of regions, these do not become individual polygons, though it can look like it.
I see it as a real bug. If I create a 20-sided opaque polygon, with the
first point not being duplicated at the end, that produces a filled shape,
with the last edge not drawn. Then I add a blank line at the other side
(i.e. between points 10 and 11) of the polygon, and suddenly the last edge
becomes drawn. Surely that's a bug ?
No. It is the way the engine works with graphics in relation to the opaque property.
But I see no need to add a new property - the existence or non-existence of
blank lines already provides enough expressive power to describe everything
needed. Unfortunately, both the engine and the documentation would need to
change.
-- Alex.
I like this, so many different ways to look at the same object, thing, problem or whatever.
I am sorry if what I say is not correct from the point of view of a particular language.
But there is something like: if your first programming language was C, you tend to look at any other language from the point of view of the first one you learned. And with assembler this tendency is even worse :-))
For Geoff's famous starbattle: go stack url "http://www.inspiredlogic.com/rev/starbattle.rev";;
Have fun.
Greetings, WA
_______________________________________________ use-revolution mailing list [EMAIL PROTECTED] http://lists.runrev.com/mailman/listinfo/use-revolution
