use masking:

glyph images are now used as masks over the "leds_on" image
instead of the glyphs themselves looking like they're made of LEDs.

Makes font files much simpler, easier to draw, makes LEDs easier
to re-texture.

White for "on" LEDs, black for "off"

Also optimized all images (optipng, pngcrush)

init.lua

@@ -369,23 +369,17 @@ for i = 31, 255 do
 	local groups = { cracky = 2, not_in_creative_inventory = 1}
 	local light = LIGHT_MAX-2
 	local description = S("LED marquee panel ("..i..")")
-	local tiles = {
+	local leds = "led_marquee_char_"..i..".png^[mask:led_marquee_leds_on.png"
-				{ name="led_marquee_base.png", color="white"},
-				{ name="led_marquee_leds_off.png", color="white"},
-				"led_marquee_char_"..i..".png",
-			}
 
 	if i == 31 then
-		tiles = {
+		leds ={
-			{ name="led_marquee_base.png", color="white"},
+			name = "led_marquee_char_31.png^[mask:led_marquee_leds_on_cursor.png",
-			{ name="led_marquee_leds_off.png", color="white"},
-				{
-				name = "led_marquee_char_31.png",
 			animation = {type = "vertical_frames", aspect_w = 32, aspect_h = 32, length = 0.75}
 		}
-		}
 	end
 
+	local wimage
+
 	if i == 32 then
 		groups = {cracky = 2}
 		light = nil
@@ -397,7 +391,11 @@ for i = 31, 255 do
 		description = description,
 		drawtype = "mesh",
 		mesh = "led_marquee.obj",
-		tiles = tiles,
+		tiles = {
+			{ name = "led_marquee_base.png", color = "white" },
+			{ name = "led_marquee_leds_off.png", color = "white" }
+		},
+		overlay_tiles = { "", leds },
 		inventory_image = wimage,
 		wield_image = wimage,
 		palette="led_marquee_palette.png",
@@ -412,6 +410,11 @@ for i = 31, 255 do
 			reset_meta(pos)
 		end,
 		on_receive_fields = function(pos, formname, fields, sender)
+			local name = sender:get_player_name()
+			if minetest.is_protected(pos, name) and not minetest.check_player_privs(name, {protection_bypass=true}) then
+				minetest.record_protection_violation(pos, name)
+				return
+			end
 			if (fields.channel) then
 				minetest.get_meta(pos):set_string("channel", fields.channel)
 			end

models/led_marquee.obj

@@ -21,10 +21,6 @@ v -0.500000 -0.453125 0.468750
 v -0.500000 -0.453125 -0.468750
 v -0.500000 -0.437500 -0.484375
 v -0.500000 -0.437500 -0.500000
-v 0.500000 -0.449125 -0.468750
-v -0.500000 -0.449125 -0.468750
-v -0.500000 -0.449125 0.468750
-v 0.500000 -0.449125 0.468750
 vt 0.681855 0.961799
 vt 0.723891 0.992824
 vt 0.723891 0.000000
@@ -69,10 +65,6 @@ vt 0.000000 0.000000
 vt 1.000000 0.000000
 vt 1.000000 1.000000
 vt 0.000000 1.000000
-vt 0.000000 0.000000
-vt 1.000000 0.000000
-vt 1.000000 1.000000
-vt 0.000000 1.000000
 vn 1.0000 0.0000 0.0000
 vn 0.0000 -1.0000 -0.0000
 vn -1.0000 0.0000 0.0000
@@ -106,7 +98,5 @@ f 7/26/8 6/38/8 19/19/8
 f 19/19/6 6/38/6 5/20/6
 f 15/22/6 10/39/6 9/23/6
 f 8/25/7 17/40/7 16/24/7
-g Cube_Cube_LEDs_Cube_Cube_LEDs_leds_off
+g Cube_Cube_LEDs_Cube_Cube_LEDs_base_led_marquee_leds_off.png
 f 1/41/6 2/42/6 3/43/6 4/44/6
-g Cube_Cube_LEDs_Cube_Cube_LEDs_leds_on
-f 21/45/6 22/46/6 23/47/6 24/48/6