Graffiti centers on where you click. (#9255)

* Graffiti centers on where you click.

* Oversights, and pixelshifted engravings.

* Better returns

code/game/objects/effects/decals/crayon.dm

@@ -4,25 +4,38 @@
 	icon = 'icons/obj/rune.dmi'
 	plane = DIRTY_PLANE
 	anchored = 1
+	var/art_type
+	var/art_color
+	var/art_shade
 
 /obj/effect/decal/cleanable/crayon/Initialize(var/ml, main = "#FFFFFF",shade = "#000000",var/type = "rune")
 	. = ..(ml, 0) // mapload, age
 	name = type
 	desc = "A [type] drawn in crayon."
 
+	// Persistence vars.
+	art_type = type
+	art_color = main
+	art_shade = shade
+
 	switch(type)
 		if("rune")
 			type = "rune[rand(1,6)]"
 		if("graffiti")
 			type = pick("amyjon","face","matt","revolution","engie","guy","end","dwarf","uboa")
 
-	var/icon/mainOverlay = new/icon('icons/effects/crayondecal.dmi',"[type]",2.1)
-	var/icon/shadeOverlay = new/icon('icons/effects/crayondecal.dmi',"[type]s",2.1)
+	update_icon()
 
-	mainOverlay.Blend(main,ICON_ADD)
-	shadeOverlay.Blend(shade,ICON_ADD)
+	add_hiddenprint(usr)
+
+/obj/effect/decal/cleanable/crayon/update_icon()
+	cut_overlays()
+	var/icon/mainOverlay = new/icon('icons/effects/crayondecal.dmi',"[art_type]",2.1)
+	var/icon/shadeOverlay = new/icon('icons/effects/crayondecal.dmi',"[art_type]s",2.1)
+
+	mainOverlay.Blend(art_color,ICON_ADD)
+	shadeOverlay.Blend(art_shade,ICON_ADD)
 
 	add_overlay(mainOverlay)
 	add_overlay(shadeOverlay)
-
-	add_hiddenprint(usr)
+	return