OpenEuphoria

Re: sorting points or rectangles

• Posted by tone.skoda at siol.net Feb 23, 2002
• 513 views

It's any rectangle that is partly inside the specified big rectangle.
I do need to know how much it is inside for clipping, but that is not a
problem.


----- Original Message -----
From: "Dan Moyer" <DANIELMOYER at prodigy.net>
To: "EUforum" <EUforum at topica.com>
Subject: Re: sorting points or rectangles


>
> Tone,
>
> Ok, no tilted rectangles.
>
> But let me get this straight:  is it only rectangles *wholly* inside
another
> rectangle you're concerned with, or is it any rectangle that is even
> *partly* inside another that concerns you?  And do you need to know how
much
> of one is inside the other, perhaps for clipping purposes?
>
> Dan
>
> ----- Original Message -----
> From: <tone.skoda at siol.net>
> To: "EUforum" <EUforum at topica.com>
> Sent: Thursday, February 21, 2002 3:53 PM
> Subject: Re: sorting points or rectangles
>
>
> > I get it.
> > No, I don't have any situations like that.
> > My rectangles are all about same size and don't have whole numbers for
> > coordinates, like this 100000.321.
> >
> > Something like that:
> >
> >  Please view in a fixed-width font such as
> >                  Courier.
> >
> >   +--------+------+-----+---------+
> >   |        |      |     |       +-+-------+
> >   |        |      |    ++-------+-+--+    |
> >   |    +---+------+----++-+     | |  |    |
> >   +----+---+------+----++-+-----+-+  |    |
> >        |               |  |     |    |    |
> >        |+--------+     |  |     +----+----+
> >        ||        |     |  |          |
> >        ++--------+-----+--+          |
> >         |        |     |             |
> >         |        |     +-------------+
> >         +--------+
> >
> >
> > ----- Original Message -----
> > From: "Dan Moyer" <DANIELMOYER at prodigy.net>
> > To: "EUforum" <EUforum at topica.com>
> > Sent: Friday, February 22, 2002 3:44 AM
> > Subject: Re: sorting points or rectangles
> >
> >
> > > tone,
> > >
> > > A rectangle could be *tilted* with respect to the screen, but still
have
> 4
> > > 90 degree corners.  Do you have any situations like that to consider?
> > >
> > > Dan Moyer
> > >
> > > ----- Original Message -----
> > > From: <tone.skoda at siol.net>
> > > To: "EUforum" <EUforum at topica.com>
> > > Sent: Thursday, February 21, 2002 4:31 PM
> > > Subject: Re: sorting points or rectangles
> > >
> > >
> > > > ----- Original Message -----
> > > > From: "Dan Moyer" <DANIELMOYER at prodigy.net>
> > > >
> > > > > ... if the edges of the rectangles are all vertical and horizontal
> > with
> > > > respect to
> > > > > the coordinate system (the screen).
> > > >
> > > > I don't understand this quite. Rectangles allways have two
horizontal
> > and
> > > > two vertical edges. If edges are not horizontal or vertical then
that
> > > would
> > > > be paralelogram or whatever, no?
> > > >
> > > > > Do you need to handle conditions other
> > > > > than that?
> > > >
> > > > No. You all responded with functions how to find out if (and how)
> > > rectangle
> > > > is inside rectangle.
> > > > I have around 10.000 rectangles and I have to get all rectangles
which
> > > have
> > > > at least one of their four points inside a big rectangle.
> > > > I want to be able to use binary search on sorted rectangles for
speed.
> > > >
> > > > If I do it like this it is too slow:
> > > >
> > > > function get_rects_inside_rect (sequence rectangles, sequence
> big_rect)
> > > >     sequence rects_inside
> > > >     sequence rect
> > > >     rects_inside = {}
> > > >     for int i = 0 to length (rects) do
> > > >         rect = rects [i]
> > > >         if is_rect_partially_inside_rect (rect, big_rect)  then
> > > >             rects_inside = append (rects_inside, rect)
> > > >         end if
> > > >    end for
> > > >    return rects_inside
> > > > end function
> > > >
> > > > A little faster it would be if I woluld somehow sort them by their
> > left-x,
> > > > or something similar. Unclear to me right now.
> > > >
> > > >
>
>
>