Vowel contouring

For today's daily dose of my conlang, I shall introduce part of the noun
morphology. As I've already described in another post, there are five noun
cases in my conlang. Now we take a peek at how they are formed lexically:

We'll start with the word "t3c3i'" [Kirsh] /tV"cV"?i/, "wall" or
"protective barrier". For simplicity, we restrict our attention to the
singular forms. The singular stem of "t3c3i'" is "tacww'". Here are the
forms:

Originative:    t3cw0'          /tV"cu"?O/
Receptive:      tac3u'          /tacV"?u/
Instrumental:   tacwa'          /tacu"?a/
Conveyant:      tac33'          /tV"cV":/
Locative:       t3c3i'          /tV"cV"?i/

To understand how these forms are derived, we need to understand "vowel
contouring" in the language. The language arranges its 9 vowels into a 3
by 3 table:
        u       w       y
        o       3       i
        0       a       e

When inflecting for case, three vowel-change points are identified:
1) the "tail vowel": the vowel in the final syllable
2) the "middle vowel": the vowel on the stress syllable. If the stress
   syllable coincides with the final syllable, the "tail vowel" takes
   precedence, and the rules pertaining to the "middle vowel" are ignored.
3) the "head vowel": the vowel on the first syllable of the stem (but
   *following* any prefixes). If the first syllable of the stem coincides
   with the stress syllable or the final syllable, then the "middle" or
   "tail" vowel takes precedence, and the rules pertaining to the head
   vowel are ignored.
4) when the noun stem ends with a long syllable, in all cases except the
   conveyant, the long vowel is split into two short vowels before (1),
   (2), and (3) are applied. If the original long syllable was the stress
   syllable, then the middle vowel is the first short vowel after the
   split, and the tail vowel is the second. After inflection, if the two
   short vowels are identical, they are merged back into a long vowel.

Now, the following table shows the inflection rules for each of the 5
forms. The symbol (^) means that if the corresponding vowel is a 3rd row
vowel (see vowel table above), it becomes a 2nd row vowel of the same
column; otherwise it is unchanged. The symbol (v) means that if the
corresponding vowel is a 1st row vowel, it becomes a 2nd row vowel of the
same column; otherwise it is unchanged. The symbol (=) means that the
vowel is replaced with a 2nd *column* vowel of the same row. The symbol
for a vowel (0,u,a,3,i) means that the corresponding vowel is replaced
with that vowel. The absence of a symbol means the vowel is unchanged.

                head    middle  tail
originative:    ^       ^       0
receptive:      v       v       u
instrumental:           =       a
conveyant:      =               3
locative:       ^       v       i

For example, to derive the locative form from the stem "tacww'", we first
split the long vowel "ww" (as per rule (4)):
        tacww' --> tacw-w'
Next, by rule (4), we identify the head vowel "a", the middle vowel the
first "w" and the tail vowel the second "w". Now we apply the vowel
contouring rule for the locative:
- "a" is a 3rd row vowel, and the rule is (^); so we replace it with a 2nd
  row vowel of the same column, which is "3".
- The first "w" is a 1st row vowel, and the rule is (v); so we replace it
  with a 2nd row vowel of the same column, which again is "3".
- Finally, the second "w" is replaced with "i".
So, we obtain the form "t3c3i'".

*Note: these rules may seem totally artificial and arbitrary, but believe
you me, there is a reason why "3" appears twice in the derivation of
"t3c3i'" above. I hand-crafted these rules with extra care to ensure a
pleasant-sounding (to me that is :-P) vowel contouring. If you don't
believe me, take a look at the forms of "pii'z3di" (man) below, and notice
that the first two syllables "pii'z3" is unchanged in all except in the
instrumental. There is a reason why I chose those particular vowels in the
noun stem! :-)

Noun stem: pii'z3da
Originative:    pii'z3d0        /pi:zV"dO/
Receptive:      pii'z3du        /pi:zV"du/
Instrumental:   p33'z3da        /pV":zV"da/
Conveyant:      pii'z3d3        /pi:zV"d3/
Locative:       pii'z3di        /pi:zV"di/


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