Texture Load Watcher

ContinueOnTextureLoad.lua

local TextureParent = CreateFrame("Frame")
TextureParent:SetPoint("BOTTOMRIGHT", nil, "TOPLEFT")
TextureParent:SetSize(1, 1)

local TexturePool = CreateTexturePool(TextureParent)
local WatcherPool = CreateFramePool("Frame", TextureParent)

function ContinueOnTextureLoad(path, callback)
    local texture = TexturePool:Acquire()
    local watcher

    local OnTextureLoad = function()
        if texture:GetTextureFileID() then
            xpcall(callback, CallErrorHandler, path, true, texture:GetSize())
        else  -- Path doesn't exist.
            xpcall(callback, CallErrorHandler, path, false, 0, 0)
        end

        if watcher then
            watcher:SetScript("OnSizeChanged", nil)
            WatcherPool:Release(watcher)
        end

        texture:SetTexture(nil)
        TexturePool:Release(texture)
    end

    texture:SetPoint("BOTTOMRIGHT")
    texture:SetTexture(path)
    texture:Show()

    if texture:GetRect() then
        OnTextureLoad();
    else
        watcher = WatcherPool:Acquire()
        watcher:SetAllPoints(texture)
        watcher:SetScript("OnSizeChanged", OnTextureLoad)
        watcher:Show()
    end
end