ChangeTurf()... We meet again...

code/WorkInProgress/Aryn/Lighting/Engine.dm

@@ -162,6 +162,11 @@ turf/proc/RemoveLight(light/light)
 			ResetValue()
 		if(!lit_by.len) lit_by = null
 
+//Only called by ChangeTurf, because it really needs it.
+turf/proc/ResetAllLights()
+	for(var/light/light in lit_by)
+		light.Reset()
+
 turf/proc/ResetValue()
 	if(is_outside)
 		max_brightness = lighting_controller.starlight

code/game/turfs/turf.dm

@@ -233,7 +233,7 @@ var/turf_light_data/old_lights = new
 		//W.Assimilate_Air()
 
 		old_lights.copy_to(W)
-		W.ResetValue()
+		W.ResetAllLights()
 
 		if(old_opacity)
 			W.opacity = 1
@@ -257,7 +257,7 @@ var/turf_light_data/old_lights = new
 		var/turf/W = new N( locate(src.x, src.y, src.z) )
 
 		old_lights.copy_to(W)
-		W.ResetValue()
+		W.ResetAllLights()
 
 		if(air_master)
 			air_master.mark_for_update(src)