POV-Ray : Newsgroups : povray.general : Big Bug Found Server Time
11 Aug 2024 15:20:23 EDT (-0400)
  Big Bug Found (Message 1 to 10 of 10)  
From: Ken
Subject: Big Bug Found
Date: 4 Jul 1999 23:01:46
Message: <37801FC9.74AE2833@pacbell.net>
Rendering the following produces a big bug:

  camera       { location < 0, -.5, -1.7> look_at 0}
  light_source { <-10,10,-10> rgb 1}

  text       { ttf "timrom.ttf" "BIG" .5,0 translate<-0.85,   0,0>pigment{rgb 1}}
  text       { ttf "timrom.ttf" "BUG" .5,0 translate<-1.05,-.67,0>pigment{rgb 2}}

  background { rgb .35}

While not a serious big bug it is a big bug none the less.

-- 
Ken Tyler

mailto://tylereng@pacbell.net


Post a reply to this message

From: Alan Kong
Subject: Re: Big Bug Found
Date: 5 Jul 1999 01:11:14
Message: <37803cd4.53747224@news.povray.org>
On Sun, 04 Jul 1999 20:00:25 -0700, Ken <tyl### [at] pacbellnet> wrote:

  Hi, Ken. You are correct. Using your scene code I was able to reproduce
the big bug.

>Rendering the following produces a big bug:
>
>  camera       { location < 0, -.5, -1.7> look_at 0}
>  light_source { <-10,10,-10> rgb 1}
>
>  text       { ttf "timrom.ttf" "BIG" .5,0 translate<-0.85,   0,0>pigment{rgb 1}}
>  text       { ttf "timrom.ttf" "BUG" .5,0 translate<-1.05,-.67,0>pigment{rgb 2}}
>
>  background { rgb .35}
>
>While not a serious big bug it is a big bug none the less.

  The following scene source, however, will squash the big bug:

camera { location < 0, -.5, -1.7> look_at 0}

light_source { <-10,10,-10> rgb 1}

text { ttf "timrom.ttf" "BIG" .5,0 scale <1, .2, 1>
  translate<-0.85,-.525,0>
  pigment{rgb 1}
}

text { ttf "timrom.ttf" "BUG" .5,0 scale <1, .2, 1>
  translate<-1.05,-.67,0>
  pigment{rgb 2}
}

background { rgb .35}

-- 
Alan
--------------------------------------------------------------------
http://www.povray.org - Home of the Persistence of Vision Ray Tracer
news.povray.org - where POV-Ray enthusiasts around the world can get
together to exchange ideas, information, and experiences with others
--------------------------------------------------------------------


Post a reply to this message

From: Ken
Subject: Re: Big Bug Fix Found
Date: 5 Jul 1999 05:04:40
Message: <378074CB.EE357A9E@pacbell.net>
Alan Kong wrote:
> 
> On Sun, 04 Jul 1999 20:00:25 -0700, Ken <tyl### [at] pacbellnet> wrote:
> 
>   Hi, Ken. You are correct. Using your scene code I was able to reproduce
> the big bug.

>   The following scene source, however, will squash the big bug:
> 
> camera { location < 0, -.5, -1.7> look_at 0}
> 
> light_source { <-10,10,-10> rgb 1}
> 
> text { ttf "timrom.ttf" "BIG" .5,0 scale <1, .2, 1>
>   translate<-0.85,-.525,0>
>   pigment{rgb 1}
> }
> 
> text { ttf "timrom.ttf" "BUG" .5,0 scale <1, .2, 1>
>   translate<-1.05,-.67,0>
>   pigment{rgb 2}
> }
> 
> background { rgb .35}
> 
> --
> Alan

  While your solution to the Big Bug works it is a bit messy. I have a
Big Bug fix that I would like to submit for your approval. Besides fixing
this particular bug it has the potential of fixing many other Bugs as
well:

  camera       { location < 0, 0, -1.9> look_at 0}
  light_source { <-1,1,-510> rgb 1}

  text { ttf "timrom.ttf" "RAID" .5,0  scale <1,2,1> 
    translate<-1.2,-.35,0>
   pigment { rgb 2 }
  }


  All kidding aside there does appear to be something wrong with the first
example I presented. If you look at the text object on top you will note
where it intersects the text object on the bottom the bottom of the top
text object appears to be thicker in the z direction than the top of the
text object on the bottom. Shouldn't they be a uniform thickness both top
and bottom for both text objects bottom and top ?

Is this a Big Bug BUG ?

-- 
Ken Tyler

mailto://tylereng@pacbell.net


Post a reply to this message

From: Jim Kress
Subject: Re: Big Bug Fix Found
Date: 5 Jul 1999 15:04:49
Message: <378101d1@news.povray.org>
You sure this isn't just an optical illusion caused by the viewing
persepective?  If I change the viewing point to <0, 0.5, -1.7> the problem
seems to go away.  It might also be an artifact of the lighting, since when
I switch the RGB values the top letters appear to be bigger than the bottom.

--
Jim

Check out my web site  http://www.kressworks.com/
It'll blow your mind (politically), stimulate your senses (artistically)
and provide scientific insights that boggle the mind!

Ken <tyl### [at] pacbellnet> wrote in message
news:378074CB.EE357A9E@pacbell.net...
>
>
> Alan Kong wrote:
> >
> > On Sun, 04 Jul 1999 20:00:25 -0700, Ken <tyl### [at] pacbellnet> wrote:
> >
> >   Hi, Ken. You are correct. Using your scene code I was able to
reproduce
> > the big bug.
>
> >   The following scene source, however, will squash the big bug:
> >
> > camera { location < 0, -.5, -1.7> look_at 0}
> >
> > light_source { <-10,10,-10> rgb 1}
> >
> > text { ttf "timrom.ttf" "BIG" .5,0 scale <1, .2, 1>
> >   translate<-0.85,-.525,0>
> >   pigment{rgb 1}
> > }
> >
> > text { ttf "timrom.ttf" "BUG" .5,0 scale <1, .2, 1>
> >   translate<-1.05,-.67,0>
> >   pigment{rgb 2}
> > }
> >
> > background { rgb .35}
> >
> > --
> > Alan
>
>   While your solution to the Big Bug works it is a bit messy. I have a
> Big Bug fix that I would like to submit for your approval. Besides fixing
> this particular bug it has the potential of fixing many other Bugs as
> well:
>
>   camera       { location < 0, 0, -1.9> look_at 0}
>   light_source { <-1,1,-510> rgb 1}
>
>   text { ttf "timrom.ttf" "RAID" .5,0  scale <1,2,1>
>     translate<-1.2,-.35,0>
>    pigment { rgb 2 }
>   }
>
>
>   All kidding aside there does appear to be something wrong with the first
> example I presented. If you look at the text object on top you will note
> where it intersects the text object on the bottom the bottom of the top
> text object appears to be thicker in the z direction than the top of the
> text object on the bottom. Shouldn't they be a uniform thickness both top
> and bottom for both text objects bottom and top ?
>
> Is this a Big Bug BUG ?
>
> --
> Ken Tyler
>
> mailto://tylereng@pacbell.net


Post a reply to this message

From: Ken
Subject: Re: Big Bug Fix Found
Date: 5 Jul 1999 15:24:56
Message: <37810611.A3CB8F97@pacbell.net>
Jim Kress wrote:
> 
> You sure this isn't just an optical illusion caused by the viewing
> persepective?  If I change the viewing point to <0, 0.5, -1.7> the problem
> seems to go away.  It might also be an artifact of the lighting, since when
> I switch the RGB values the top letters appear to be bigger than the bottom.
> 
> --
> Jim

 Arranging it once again and incoporating one of your changes it is still
evident the the object on top is thicker than the object on the bottom -
I think.



  camera       { location < 0, 0, -.5> look_at 0}
  light_source { <-4,4,-3> rgb 1}

  text       { ttf "timrom.ttf" "BIG" .5,0 translate<-0.85,   0,0>pigment{rgb 2}}
  text       { ttf "timrom.ttf" "BUG" .5,0 translate<-1.05,-.67,0>pigment{rgb 1}}

  background { rgb .65}

-- 
Ken Tyler

mailto://tylereng@pacbell.net


Post a reply to this message

From: Ken
Subject: Re: Big Bug Fix Found
Date: 5 Jul 1999 16:35:03
Message: <3781167D.EA988AC5@pacbell.net>
Ken wrote:

>  Arranging it once again and incoporating one of your changes it is still
> evident the the object on top is thicker than the object on the bottom -
> I think.
> 
>   camera       { location < 0, 0, -.5> look_at 0}
>   light_source { <-4,4,-3> rgb 1}
> 
>   text       { ttf "timrom.ttf" "BIG" .5,0 translate<-0.85,   0,0>pigment{rgb 2}}
>   text       { ttf "timrom.ttf" "BUG" .5,0 translate<-1.05,-.67,0>pigment{rgb 1}}
> 
>   background { rgb .65}

  The most compelling argument yet that there is a possible problem with
the text object comes when we render the following example. In a difference
operation with two equally thick objects we would expect a coincident surface
problem. Evidence from the following example shows this not to be the case
because there is still some of the differencing object remaing in the back
of the lower differenced text object. This indicates to me that the text
object on top is offset slightly in the -z diffection where on would instead
expect the surfaces to be flush with one another. It might be a precision
problem on the Windows platform and I would like to hear from someone
running on a different platform if they too witness what I am seeing.

  camera       { location < 0, .1, -.3> look_at 0}
  light_source { <-4,4,-3> rgb 1}
  
  difference {
  text       { ttf "timrom.ttf" "BUG" .5,0 translate<-1.05,-.67,0>pigment{rgb 1}}
  text       { ttf "timrom.ttf" "BIG" .5,0 translate<-0.85,   0,0>pigment{rgb 2}}
             }
  background { rgb .65}

-- 
Ken Tyler

mailto://tylereng@pacbell.net


Post a reply to this message

From: Alan Kong
Subject: Re: Big Bug Still Exsists
Date: 5 Jul 1999 17:01:25
Message: <37841c8a.53999319@news.povray.org>
On Mon, 05 Jul 1999 13:03:54 -0700, Ken <tyl### [at] pacbellnet> wrote:

>In a difference
>operation with two equally thick objects we would expect a coincident surface
>problem. Evidence from the following example shows this not to be the case
>because there is still some of the diffeneced object remaing in the back
>of the lower differenced text object. This indicates to me that the text
>object on top is offset slightly in the -z [..]

  Hi, Ken. Rendered at 800w by 600h, +am2 +a0.2, the following modification
to the camera and light source location make it even more obvious:

//camera       { location < 0, -.5, -1.7> look_at 0}
camera       { location < 0, -0.2, -0.01> look_at 0}

//light_source { <-10,10,-10> rgb 1}
light_source { <-10,-10,-10> rgb 1}

text       { ttf "timrom.ttf" "BIG" .5,0
  translate<-0.85, 0,0>
  pigment{rgb 1}
}

text       { ttf "timrom.ttf" "BUG" .5,0
  translate<-1.05,-.67,0>
  pigment{rgb 2}
}

background { rgb .35}

-- 
Alan
--------------------------------------------------------------------
http://www.povray.org - Home of the Persistence of Vision Ray Tracer
news.povray.org - where POV-Ray enthusiasts around the world can get
together to exchange ideas, information, and experiences with others
--------------------------------------------------------------------


Post a reply to this message

From: Alan Kong
Subject: Re: Big Bug Still Exsists
Date: 5 Jul 1999 17:56:59
Message: <37812947.57260714@news.povray.org>
On Mon, 05 Jul 1999 13:03:54 -0700, Ken <tyl### [at] pacbellnet> wrote:

>It might be a precision
>problem on the Windows platform and I would like to hear from someone
>running on a different platform if they too witness what I am seeing.

  Just traced it using MS-DOS POV-Ray v3.1e, with the same results using
your scene with my modified camera and light source locations. I can still
see the edge of the text on top hanging over the bottom word.

-- 
Alan
--------------------------------------------------------------------
http://www.povray.org - Home of the Persistence of Vision Ray Tracer
news.povray.org - where POV-Ray enthusiasts around the world can get
together to exchange ideas, information, and experiences with others
--------------------------------------------------------------------


Post a reply to this message

From: Ken
Subject: Re: Big Bug Still Exsists
Date: 5 Jul 1999 18:07:17
Message: <37812C15.2F1784A3@pacbell.net>
Alan Kong wrote:
> 
> On Mon, 05 Jul 1999 13:03:54 -0700, Ken <tyl### [at] pacbellnet> wrote:
> 
> >It might be a precision
> >problem on the Windows platform and I would like to hear from someone
> >running on a different platform if they too witness what I am seeing.
> 
>   Just traced it using MS-DOS POV-Ray v3.1e, with the same results using
> your scene with my modified camera and light source locations. I can still
> see the edge of the text on top hanging over the bottom word.
> 
> --
> Alan

  When I started this thread it was simply intended to be a bit of Pov humor
and I did not for a moment think there was a bug in Pov's text object. Now
I am not so sure that this is indeed the case. Before I make a report of
this does anyone else concur there is cause for concern ?

P.S. Thanks for the input Alan.

-- 
Ken Tyler

mailto://tylereng@pacbell.net


Post a reply to this message

From: Colin Fleming
Subject: Re: Big Bug Still Exsists
Date: 6 Jul 1999 10:36:25
Message: <378213D7.F9C7ED69@csi.com>
I would agree with Jim Kress and say that its an optical illusion, if
you look at the bottom of the letter "I" with the top of the letter "U",
the "I" sits on top of the "U" neatly (perfectly!).

Colin ;)


Ken wrote:
> 
> 
>   When I started this thread it was simply intended to be a bit of Pov humor
> and I did not for a moment think there was a bug in Pov's text object. Now
> I am not so sure that this is indeed the case. Before I make a report of
> this does anyone else concur there is cause for concern ?


Post a reply to this message

Copyright 2003-2023 Persistence of Vision Raytracer Pty. Ltd.