local time = 0
    local function col(r,g,b) return bit.lshift(math.floor(r),16)+bit.lshift(math.floor(g),8)+math.floor(b) end
    app:AddHook("RENDER", "wat", function(app, delta)
        local surface = sdl.SDL_GetWindowSurface(app.window)
        local pixels = ffi.cast("uint32_t*", surface.pixels)
        local width, height = surface.w, surface.h
        for yc = 0, height-1 do
            for xc = 0, width-1 do
                pixels[xc+yc*height] = col(time%1*255, 0, 0)
            end
        end
    end)
    while app:Update() do
        time = tonumber(sdl.SDL_GetTicks())/1000
        print(time)
        app:Render()
    end