otravi_UnitFrames.lua
---------------------
CreateFramework:
		self.frames[u].RaidTarget = self.frames[u]:CreateTexture(nil, "OVERLAY")
		self.frames[u].RaidTarget:Hide()
		self.frames[u].RaidTarget:SetTexture("Interface\\TargetingFrame\\UI-RaidTargetingIcons")
		self.frames[u].RaidTarget:SetWidth(26)
		self.frames[u].RaidTarget:SetHeight(26)
		self.frames[u].RaidTarget:SetPoint("CENTER", self.frames[u], "TOPLEFT")

functions:
	updateRaidTarget = function(self, u)
		local index = GetRaidTargetIndex(u)
		if self.frames[u].RaidTarget and index then
			self:updateRaidTargetIcon(u, index)
			self.frames[u].RaidTarget:Show()
		else
			self.frames[u].RaidTarget:Hide()
		end
	end,

	updateRaidTargetIcon = function(self, u, index)
		index = index - 1
		local left, right, top, bottom
		local coordIncrement = RAID_TARGET_ICON_DIMENSION / RAID_TARGET_TEXTURE_DIMENSION
		left = mod(index , RAID_TARGET_TEXTURE_COLUMNS) * coordIncrement
		right = left + coordIncrement
		top = floor(index/ RAID_TARGET_TEXTURE_ROWS) * coordIncrement
		bottom = top + coordIncrement
		self.frames[u].RaidTarget:SetTexCoord(left, right, top, bottom)
	end,

individual frame .lua files
---------------------------
Initialize:
	self:RegisterEvent("RAID_TARGET_UPDATE", "updateRaidTarget")

Enable:
	oUF:updateRaidTarget("target") --or "player" or "targettarget", etc.

functions:
	updateRaidTarget = function(self)
		oUF:updateRaidTarget("target")
	end,