"Francois Labreque" <fla### [at] attglobalnet> wrote :
>
> box {
>     < 2.875, 5.5, 3.6333333 >
>     < 7.142857, 9.3, 4 >
> }
>

    Modeler syndrome.

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Ron Parker <ron### [at] povrayorg> wrote in message
news:slr### [at] linuxparkerrfwicom...
> On Sun, 12 Mar 2000 07:56:08 -0500, Bill DeWitt wrote:
> >Since most people use a unit, at origin object, then scale
> >and translate, it could save tons of typing.
>
> Who is this "most people" you talk about?  Most modelers do that, but
> I would think most people make the box where they want it.  I know I
> do.

I'm suprised - I'm trying to write a short newbie tutorial on object
transformations, and one of my general rules is always create objects with a
known point at <0,0,0>. Don't you lose track of where you objects are going
to end up if you scale them? (or at least find it harder).

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Tom Melly wrote:

> I'm suprised - I'm trying to write a short newbie tutorial on object
> transformations, and one of my general rules is always create objects with a
> known point at <0,0,0>. Don't you lose track of where you objects are going
> to end up if you scale them? (or at least find it harder).

I completely agree. When I was a newbie, my permanent problem was that
I defined objects "directly" and always lost them after a few translates and
rotates.
I often had to "pile" transform statements to obtain a desired effect, and lost
a
lot of time looking for disappearing primitives (no VFAQ then !).
This problem was solved when I started creating them at <0,0,0>
and applied the transforms afterwards. I find it easier to apply textures too.
This can't be a general rule, though. Chain-like objects can be often created
more
easily using absolute coordinates (when using loops at least) since the end
points
of a primitive can be used as the starting points of the next.

G.

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On Mon, 13 Mar 2000 17:27:07 -0000, Tom Melly wrote:
>I'm suprised - I'm trying to write a short newbie tutorial on object
>transformations, and one of my general rules is always create objects with a
>known point at <0,0,0>. Don't you lose track of where you objects are going
>to end up if you scale them? (or at least find it harder).

If you create it where you want it, you don't need to scale it.  I don't see
the problem here.

Okay, to be honest, I still follow the rule of creating things at the origin.
But if I'm going to make a simple stool, I do this:

 union {
   box {<-6, 36, -6>,<6,37,6>}
   intersection {
     box {<-8,0,-8>,<8,36.5,8>}
     cylinder { <-5,0,-5>, <-4,36.5,-4>, .5 }
     cylinder { < 5,0,-5>, < 4,36.5,-4>, .5 }
     cylinder { <-5,0, 5>, <-4,36.5, 4>, .5 }
     cylinder { < 5,0, 5>, < 4,36.5, 4>, .5 }
   }
 }

That is, I create the parts of the stool where they should be, relative to the
fixed point on the stool that I have chosen to have at the origin (in this case,
a point on the floor directly under the center.)  To me, this looks a lot 
cleaner than trying to create and translate and rotate and scale all those 
components to get the desired result.  I will still translate and rotate the 
stool to put it where I want it (but I won't scale it, because it's already to 
scale.)

The exception, of course, is when I need an ellipsoid or a torus.  Those have to
be created at the origin.  (In fact, I wish there were an alternate syntax for
toruses that took a center and an axis so I could work with them without having
to wave my left hand around to figure out the rotations.)

-- 
These are my opinions.  I do NOT speak for the POV-Team.
The superpatch: http://www2.fwi.com/~parkerr/superpatch/
My other stuff: http://www2.fwi.com/~parkerr/traces.html

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"Ron Parker" <ron### [at] povrayorg> wrote :
>  (In fact, I wish there were an alternate syntax for
> toruses that took a center and an axis so I could work with them without
having
> to wave my left hand around to figure out the rotations.)

    I have almost convinced my family and friends that waving your hands in
the air, staring into space and  even pounding one hand against your temple
while apparently grasping at and manipulating something invisible with your
eyes tightly shut is the way we communicate with the POVray Program Goddess.

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On 12 Mar 2000 15:11:48 -0500, ron### [at] povrayorg (Ron Parker)
wrote:
>Who is this "most people" you talk about?  Most modelers do that, but
>I would think most people make the box where they want it.  I know I
>do.

I usually do as well, but it might be handy for include files that are
trying to be as universal as possible. Having all you include-file
objects oriented in a similar manner can be handy in the main scene
file.

Later,
Glen Berry

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On Tue, 14 Mar 2000, Glen Berry wrote:

> On 12 Mar 2000 15:11:48 -0500, ron### [at] povrayorg (Ron Parker)
> wrote:
> >Who is this "most people" you talk about?  Most modelers do that, but
> >I would think most people make the box where they want it.  I know I
> >do.
> 
> I usually do as well, but it might be handy for include files that are
> trying to be as universal as possible. Having all you include-file
> objects oriented in a similar manner can be handy in the main scene
> file.

so my method of making ALL my objects at 0,0,0 and then translating them
where I want them is umm....non-standard?:) (I swear I make everything at
0,0,0 then translate and rotate to where it looks right) I find it easier
but then hehehe :)


 
> Later,
> Glen Berry
> 
>

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cre### [at] belialrenonvus wrote:

> so my method of making ALL my objects at 0,0,0 and then translating them
> where I want them is umm....non-standard?:) (I swear I make everything at
> 0,0,0 then translate and rotate to where it looks right) I find it easier
> but then hehehe :)

Not at all. Your method has considerable merit and is quite popular.
There are a lot of good reasons for specifying objects at the origin
and then manipulating them from there.

-- 
Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/

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On Tue, 14 Mar 2000, Ken wrote:

> 
> 
> cre### [at] belialrenonvus wrote:
> 
> > so my method of making ALL my objects at 0,0,0 and then translating them
> > where I want them is umm....non-standard?:) (I swear I make everything at
> > 0,0,0 then translate and rotate to where it looks right) I find it easier
> > but then hehehe :)
> 
> Not at all. Your method has considerable merit and is quite popular.
> There are a lot of good reasons for specifying objects at the origin
> and then manipulating them from there.

Good!:) btw since we're kinda on the subject, how can I shorten the 
box {<-0.5,-0.5,-0.5>,<0.5,0.5,0.5> } 

see I always make my boxes that big then scale the suckers to whatever I'm
doing, the thing is typing all those 0.5's can be tiring (I get around
that with cut and paste, but still if there is some shortform...I'd love
to know it :)
 
> -- 
> Ken Tyler -  1300+ Povray, Graphics, 3D Rendering, and Raytracing Links:
> http://home.pacbell.net/tylereng/index.html http://www.povray.org/links/
> 
>

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In article 
<Pin### [at] belialrenonvus>, 
<cre### [at] belialrenonvus> wrote:

> Good!:) btw since we're kinda on the subject, how can I shorten the 
> box {<-0.5,-0.5,-0.5>,<0.5,0.5,0.5> } 
> 
> see I always make my boxes that big then scale the suckers to 
> whatever I'm doing, the thing is typing all those 0.5's can be tiring 
> (I get around that with cut and paste, but still if there is some 
> shortform...I'd love to know it :)

You could use this:
#declare Box = box {<-0.5,-0.5,-0.5>,<0.5,0.5,0.5> }

And then make your boxes with
object {Box
...
}

Or you can leave the 0's out:
box {<-.5,-.5,-.5>,<.5,.5,.5> }
And to shorten it further, you can use the feature of POV that promotes 
floats to vectors when necessary:
box {-0.5, 0.5}
or
box {-.5,.5}

This isn't as easy to immediately understand, though, and is just as 
long as using a Box variable.


If you really want to eliminate keypresses, try this:
#macro Box()
box {<-.5,-.5,-.5>,<.5,.5,.5>
#end

You would use the macro this way:

Box()
...object stuff, textures, etc go here...
}

You could use a shorter name for the macro, but you can't eliminate the 
parentheses.

-- 
Chris Huff
e-mail: chr### [at] yahoocom
Web page: http://chrishuff.dhs.org/

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