Tweak LFO script

* thin automation to prevent too dense events
* add icon (cosine wave)

scripts/lfo_automation.lua

@@ -160,6 +160,9 @@ function factory (unused_params)
          end
       end
 
+      -- remove dense events
+      al:thin (20) -- threashold of area below curve
+
       -- TODO: display the modified automation lane in the time line in order to make the change visible!
 
       -- Save undo
@@ -171,3 +174,16 @@ function factory (unused_params)
       collectgarbage()
    end
 end
+
+function icon (params) return function (ctx, width, height, fg)
+	local wh = math.min (width, height) * .5
+	local x0 = math.ceil (wh * .2)
+	local x1 = math.floor (wh * 1.8)
+	ctx:set_line_width (1)
+	ctx:set_source_rgba (ARDOUR.LuaAPI.color_to_rgba (fg))
+	ctx:move_to (x0, wh * 1.5)
+	for x = x0, x1 do
+		ctx:line_to (x, wh + math.cos (3 * math.pi * (x-x0) / (x1-x0)) * wh * .5)
+	end
+	ctx:stroke ()
+end end