[colorforth] Question about displaying text

[John Drake <jmdrake_98@xxxxxxxxx>]

Hello all,

I've made some progess on the Primary ColorForth
tutorial.  For one thing I added the formatting
to the "editor" chapter Jeff did.  Jeff included
the formatting when he wrote it, but I was unsure
how well the Wiki would take HTML so I just 
pasted raw text.  Now I realize that it handles
HTML pretty well.  I pasted Jeff's HTML and all
I had to do was attach all of the images.

http://www.quartus.net/cgi-bin/twiki/view/Main/PrimaryColorForthEditor

I also added the examples from chapter 1 of 
Starting Forth that I had documented on my
blog.

http://www.quartus.net/cgi-bin/twiki/view/Main/PrimaryColorForthGettingStarted

Note, the HTML that the blog had inserted
was much more problematic for the Wiki and
I had to do a lot of editing, but I got it
to work.

Now for my question.  I've actually finished
the rest of the example from chapter 1.  But
I'm not 100% satisfied with the results.

This is what I have so far.  I know how to
display a packed word that's on the stack.

: type fffffff0 and unpack if emit type ; then 
drop drop ;

This recursively upacks a charecter and displays.
If the charecter is 0 then we're at the end of
the word and "type" stops.  So if "hello" was
at the top of block 20 then

: ok show text 20 block type keyboard ;

would create a word to display "hello" at the
top of the screen.

I also figured out a way to use "string
variables".  Magenta variables are basically
pointers to areas of memory inside of blocks.
So if you put a magenta variable address on
the stack and add 1 to it you'll have a
pointer to the packed source code that comes
after the variable.  So I create magenta
variables and then put the string I want
directly after the variables in the form
of comments.

var s 0 ( hello )

Then

: ok show text s 1 + @ type keyboard ;

will also display "hello" on the screen.

Factoring out "1 + @ type" I get:

: stype 1 + @
: type fffffff0 and unpack if emit type ; then 
drop drop ;

But the problem is, what happens when you have
longer words?  For example:

var s 0 ( bookends )

If I do:

: ok show text s stype keyboard ;

I get:

booke

Now I can chain words together.  For example
I created a word "dword" to deal with long
words like "bookends".

: dword dup stype 1 + stype ;

Then

: ok show text s dword keyboard ;

displays:

bookends

But there HAS to be a better way.  How can
I get ColorForth to differentiate between
short words like "hello" that get packed
into a single 32 bit word and longer words
like "bookends" that take 2 32 bit words?

Clearly the editor knows how to do this
because it displays "bookends" just fine.

Regards,

John M. Drake

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