Nameplate Overhaul (#38)

* ElvUI/NamePlates: initial nameplate conversions

* More nameplate work

* Modules/Cooldowns: various CD fixes, nameplates cant show 'swipe' texture

* ElvUI/NamePlates: final nameplate polish

* Modules/Misc: add space before interrupted announcement

ElvUI/Modules/Nameplates/Plugins/Highlight.lua

@@ -0,0 +1,77 @@
+local E, L, V, P, G = unpack(ElvUI)
+local oUF = E.oUF
+
+local UnitExists = UnitExists
+local UnitIsUnit = UnitIsUnit
+
+local function MouseOnUnit(frame)
+	if frame and frame:IsVisible() and UnitExists('mouseover') then
+		return frame.unit and UnitIsUnit('mouseover', frame.unit)
+	end
+
+	return false
+end
+
+local function OnUpdate(self, elapsed)
+	if self.elapsed and self.elapsed > 0.1 then
+		if not MouseOnUnit(self) then
+			self:Hide()
+			self:ForceUpdate()
+		end
+
+		self.elapsed = 0
+	else
+		self.elapsed = (self.elapsed or 0) + elapsed
+	end
+end
+
+local function Update(self)
+	local element = self.Highlight
+
+	if element.PreUpdate then
+		element:PreUpdate()
+	end
+
+	if MouseOnUnit(self) then
+		element:Show()
+	else
+		element:Hide()
+	end
+
+	if element.PostUpdate then
+		return element:PostUpdate(element:IsShown())
+	end
+end
+
+local function Path(self, ...)
+	return (self.Highlight.Override or Update)(self, ...)
+end
+
+local function ForceUpdate(element)
+	return Path(element.__owner, 'ForceUpdate', element.__owner.unit)
+end
+
+local function Enable(self)
+	local element = self.Highlight
+	if element then
+		element.__owner = self
+		element.ForceUpdate = ForceUpdate
+		element:SetScript('OnUpdate', OnUpdate)
+
+		self:RegisterEvent('UPDATE_MOUSEOVER_UNIT', Path, true)
+
+		return true
+	end
+end
+
+local function Disable(self)
+	local element = self.Highlight
+	if element then
+		element:Hide()
+		element:SetScript('OnUpdate', nil)
+
+		self:UnregisterEvent('UPDATE_MOUSEOVER_UNIT', Path)
+	end
+end
+
+oUF:AddElement('Highlight', Path, Enable, Disable)