"JRG" <jrg### [at] hotmailcom> wrote in message
news:3c0aaac1@news.povray.org...
> If we start to put here and there exceptions to the
> rules, things won't be easier, but harder.

Kind of like the English language :)

...Chambers

Post a reply to this message

Ben Chambers wrote:

>Kind of like the English language :)

Interesting that you should mention this. I have been thinking that this
whole discussion mirrors a debate that has been raging for years in the
area of liguistics, between prescriptive and descriptive grammar.
Prescritive grammar is based on the insistance that a set of rules,
formulated over the course of time, must be followed, or the language
will degenerate. Descriptive grammar looks at the way the language is
being used and reformulates the rules to reflect current usage. I happen
to fall into the descriptive category.

Post a reply to this message

"Dave Dunn" <poi### [at] aolcom> wrote in message
news:3C0B7B79.EEF09155@aol.com...
> Ben Chambers wrote:
>
> >Kind of like the English language :)
>
> Interesting that you should mention this. I have been thinking that this
> whole discussion mirrors a debate that has been raging for years in the
> area of liguistics, between prescriptive and descriptive grammar.
> Prescritive grammar is based on the insistance that a set of rules,
> formulated over the course of time, must be followed, or the language
> will degenerate. Descriptive grammar looks at the way the language is
> being used and reformulates the rules to reflect current usage. I happen
> to fall into the descriptive category.

    Follow ups to p.o.t.

    Clearly it is both. Definitions of words must be agreed upon, while room
must be made for new usages. But I must admit that I would be more willing
to argue in favor of the former than the latter if we -had- to have it one
way or another.

    Most modern languages are quite expressive. If new words can be added as
new concepts arise, there is no need to re-define the old words. But going
to far in the 'descriptive' direction allows chaos to rule and
misunderstanding erupts in every attempt to communicate. For instance, what
if I use the word "erupts" to mean "decreases" or "is destroyed"?

Post a reply to this message

> if I can translate x*3, and rotate x*3, that I should be able to scale x*3
> without generating an error or a warning

... and this probably could generate a lot of questions from future newusers
after such simple animation render:

// animate it with clock from 0 to 1
#local Clock=1-clock;
#local V=Clock*y;
sphere{-1*y,.1 translate V}
sphere{ 0*y,.1 rotate V}
sphere{ 1*y,.1 scale V}

Warning is a good idea for newusers. Advanced one can switch it off.

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

Post a reply to this message

"Dave Dunn" <poi### [at] aolcom> wrote in message
news:3C0B7B79.EEF09155@aol.com...
> Ben Chambers wrote:
>
> >Kind of like the English language :)
>
> Interesting that you should mention this. I have been thinking that this
> whole discussion mirrors a debate that has been raging for years in the
> area of liguistics, between prescriptive and descriptive grammar.
> Prescritive grammar is based on the insistance that a set of rules,
> formulated over the course of time, must be followed, or the language
> will degenerate. Descriptive grammar looks at the way the language is
> being used and reformulates the rules to reflect current usage. I happen
> to fall into the descriptive category.

I would have to go with prescriptive.  Language is very important - not just
for communication, but also in forming our thoughts (this is the main reason
that learning a second language is so highly recommended - it forces you to
learn to restructure your thoughts).  Because of this, it is important to
follow grammatical rules.  If you do not follow the set grammar, what
happens is not a muddling of the language, but a muddling of your thought
processes.

...Chambers

Post a reply to this message

I think it makes sense the way it works at present.
But if people want to scale  quickly in one direction without the warnings
why not use a macro?

#macro ScaleIt (s)
  #local s=s*<1,1,1>
  scale <#if (s.x=0) 0 #else s.x #end,
         #if (s.y=0) 0 #else s.y #end,
         #if (s.z=0) 0 #else s.z #end>
#end


Instead of using 'scale x*5' and getting a warning or having to type 'scale
<5,1,1>' you just type
'ScaleIt(x*5)'.

I don't really see the point though, I have gotten in the habit of using
'scale <5,1,1>' for continuity sake.

-tgq

Post a reply to this message

On Mon, 3 Dec 2001 10:13:54 -0500, Trevor Quayle wrote:
> I think it makes sense the way it works at present.
> But if people want to scale  quickly in one direction without the warnings
> why not use a macro?
> 
> #macro ScaleIt (s)
>   #local s=s*<1,1,1>
>   scale <#if (s.x=0) 0 #else s.x #end,
>          #if (s.y=0) 0 #else s.y #end,
>          #if (s.z=0) 0 #else s.z #end>

Shirley some of those 0's should be 1's.

-- 
plane{-z,-3normal{crackle scale.2#local a=5;#while(a)warp{repeat x flip x}rotate
z*60#local a=a-1;#end translate-9*x}pigment{rgb 1}}light_source{-9red 1rotate 60
*z}light_source{-9rgb y rotate-z*60}light_source{9-z*18rgb z}text{ttf"arial.ttf"
"RP".01,0translate-<.6,.4,.02>pigment{bozo}}light_source{-z*3rgb-.2}//Ron Parker

Post a reply to this message

On Mon, 3 Dec 2001 10:13:54 -0500, "Trevor Quayle" <Tin### [at] hotmailcom>
wrote:

> #macro ScaleIt (s)
>   #local s=s*<1,1,1>
>   scale <#if (s.x=0) 0 #else s.x #end,
>          #if (s.y=0) 0 #else s.y #end,
>          #if (s.z=0) 0 #else s.z #end>
> #end

Excuse me, but ... what is purpose of this macro :-)
You probably want

#macro ScaleIt (s)
   #local s=s+<0,0,0>;
  scale <(s.x=0?1:s.x),(s.y=0?1:s.y),(s.z=0?1:s.z)>
#end

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

Post a reply to this message

news:oh6n0uoqibno6v3ighkgd7moo9u6cm0doi@4ax.com...
> On Mon, 3 Dec 2001 10:13:54 -0500, "Trevor Quayle"
<Tin### [at] hotmailcom>
> wrote:
>
> > #macro ScaleIt (s)
> >   #local s=s*<1,1,1>
> >   scale <#if (s.x=0) 0 #else s.x #end,
> >          #if (s.y=0) 0 #else s.y #end,
> >          #if (s.z=0) 0 #else s.z #end>
> > #end
>
> Excuse me, but ... what is purpose of this macro :-)
> You probably want
>
> #macro ScaleIt (s)
>    #local s=s+<0,0,0>;
>   scale <(s.x=0?1:s.x),(s.y=0?1:s.y),(s.z=0?1:s.z)>
> #end
>

Oops, my mistake, I did mean to use 1s not 0s, and I didn't think of the
conditional operand.  Still, there is no real point to it other than to
placate those who don't like the present results of scaling by 0.
Also what would be the difference between
#local s=s*<1,1,1>
and
#local s=s+<0,0,0>
?

-tgq

Post a reply to this message

On Mon, 3 Dec 2001 11:02:42 -0500, "Trevor Quayle" <Tin### [at] hotmailcom>
wrote:
> Also what would be the difference between
> #local s=s*<1,1,1>
> and
> #local s=s+<0,0,0>
> ?

You want put floats and vectors into this just like scale accept, right ?
But I'm not sure multiplication Vector*<1,1,1> is defined. I can't check it
becouse limitation of current 3.5 beta.

ABX
--
#declare _=function(a,b,x){((a^2)+(b^2))^.5-x}#default {pigment{color rgb 1}}
union{plane{y,-3}plane{-x,-3}finish{reflection 1 ambient 0}}isosurface{ //ABX
function{_(x-2,y,1)|_((x+y)*.7,z,.1)|_((x+y+2)*.7,z,.1)|_(x/2+y*.8+1.5,z,.1)}
contained_by{box{<0,-3,-.1>,<3,0,.1>}}translate z*15finish{ambient 1}}//POV35

Post a reply to this message