Re: LOGO-L> Re: Logo Contest Entry

[George Mills <mills@softronix.com>]

Craig Denson wrote:
> 
>  please take the following as constructive criticism. i truly admire
>  the work you've done on logo.

No problem.

> 
> >think the single index method is complicated to understand because there
> >is no relation between color 1 and color 2 etc. Kids learn about mixing
> >colors to get other colors very early (before they can type). You can
> >think
> >of setpencolor [r g b] as the "color mixer".
> 
>  this is a dangerous argument to make because the color mixing kids do
>  is not in rgb space. mixing maximum equal amounts of rgb gives white
>  in additive space and black in the subtractive space of watercolors
>  and fingerpaints. one could argue that you should have used cmy
>  space, which is subtractive.
>

I don't think it's dangerous they will learn how color mixes in RGB
by trial an error. They learned one "Scheme" they can learn another.

> 
> >What if setpensize 1 gave you a penwidth 1 and setpensize 2 gave you a
> >penwidth 10 and setpensize 3 gave you a width of 4. To me and a young
> >student that's about how much sense setpencolor with an index makes.
> >Just like
> >setpencolor you could train the student that setpensize 1 is 1, 2 is 10
> >and 3 is 4. Just like you train them that setpencolor 1 is black, 2 is
> >red etc.
> 
>   i don't think this is a good argument, either, because there isn't a
>   natural ordering of colors as there is with widths, particularly in
>   rgb space. it doesn't make sense to say that brick red is greater
>   than sea green. if you switch to lhc space then you do get a natural
>   ordering in l and c, and you could impose one in h, but even if you
>   use, say wavelength to impose the ordering, it isn't intuitively
>   obvious that green is greater than red - without a prism.
> 
>   anyway, once we get this deep, it's clear there are different
>   orderings for different purposes and your analogy with penwidth
>   fails.
> 
>   the mini-proposal i made for a palette command is how HPGL (a pen
>   plotter language) evolved into larger color spaces than the original
>   pen carriages allowed for.
> 
>   again, i'm not really agitating for change, it's just that for quick
>   and dirty stuff (of the 'pc random x' variety ) the single index
>   method is simpler.
> 
> craig

Nothing in the RGB scheme prevents you (a teacher) from building a
simple
routine to generate colors based on a single index. The reverse is much
more sloppy.

If the student can deal with angles etc. I don't believe the RGB is that
much harder to grasp and a whole lot more fun. For really young students
(no programming) they can bypass setpencolor completely and click on a
palette.

-- 
===============================================================
George Mills
email: mills@softronix.com
http://www.softronix.com
The www page contains some very powerful educational software.
Our single most important investment is our kids.


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