split out msg receiver

board.go

@@ -43,14 +43,9 @@ func animate(sz image.Point, mqMessages chan mqtt.Message) *Animation {
 		},
 	}
 }
-func (a *Animation) Next() (image.Image, <-chan time.Time, error) {
+
+func (a *Animation) useMsg() {
 	var incoming incomingMessage
-	switch {
-	case a.doorbell != (Doorbell{}):
-		a.animateDoorbell()
-	default:
-		a.animateMario()
-	}
 	select {
 	case msg := <-a.mqmsg:
 		json.Unmarshal([]byte(string(msg.Payload())), &incoming)
@@ -62,5 +57,15 @@ func (a *Animation) Next() (image.Image, <-chan time.Time, error) {
 		}
 	default:
 	}
+}
+
+func (a *Animation) Next() (image.Image, <-chan time.Time, error) {
+	switch {
+	case a.doorbell != (Doorbell{}):
+		a.animateDoorbell()
+	default:
+		a.animateMario()
+	}
+	a.useMsg()
 	return a.ctx.Image(), time.After(time.Millisecond * 50), nil
 }