Just the other party members, right? Almost purplish (on a CRT, at least)? That can happen when you tap triangle (mentioned in the game manual, pg. 8).
This "directs" your party to attack your target. Party members often give a shout as they do so (some are listed in the Battle Quotes guide). The gauge stays purplish until the direction wears off; just tap triangle again if needed.
Press R1 to target something (pg. 6), press L2 or R2 to cycle through targets, then tap triangle until each party member's gauge goes purple. Or stop at one, if that's all you need.
Directing your party is a unique feature in KH, BTW. Not found in other of the series' games, unfortunately.
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