--[[
For finding the maximum attainable player level:
    0: WoW Classic. Level 60
    1: The Burning Cruade. Level 70
    2: Wrath of the Lich King. Level 80
    3: Cataclysm. Level 85
    4: Mists of Pandaria. Level 90
    5: Warlords of Draenor. Level 100
--]]
local maxPlayerLevel = MAX_PLAYER_LEVEL_TABLE[GetExpansionLevel()]
 
-- Check if player is already max level
local displayXP = true
if UnitLevel("player") == maxPlayerLevel then
    displayXP = false
end
 
-- Disable XP bar upon hitting max level
local frame = CreateFrame("Frame")
frame:RegisterEvent("PLAYER_LEVEL_UP")
frame:SetScript("OnEvent", function(self, event, level)
    if level == maxPlayerLevel then
        displayXP = false
    end
end)

local fill = bar:GetStatusBarTexture()
local animatedTexture = bar:CreateTexture(nil, 'ARTWORK', nil, 2)
animatedTexture:SetAllPoints(fill)
animatedTexture:SetTexture('texturepath')
 
local timeSince, textureOffset = 0, 0
bar:SetScript('OnUpdate', function(self, elapsed)
  timeSince = timeSince + elapsed
  if timeSince >= 0.03 then -- speed at which it updates
    local value = self:GetValue()
    local minValue, maxValue = self:GetMinMaxValues()
    local diff = maxValue - minValue
    if diff > 0 then -- cut off horizontally to match the bar fill value, and rotate vertically however you want
      animatedTexture:SetTexCoord(0, (value - minValue) / diff, textureOffset, textureOffset + 1)
    end
    textureOffset = textureOffset + 0.02 -- how far to animate the texture each update
    if textureOffset > 1 then textureOffset = textureOffset - 1 end
    timeSince = 0
  end
end)