From f63d89eb3e372ec158355ccfc9461514a539b08c Mon Sep 17 00:00:00 2001
From: Reese Norris <reese.norris@gmail.com>
Date: Sun, 25 May 2025 14:27:07 -0700
Subject: [PATCH] only do velocity distance calculation for relevant clients

---
 fsd/handler.go    | 20 +++++++++++---------
 fsd/postoffice.go |  2 +-
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/fsd/handler.go b/fsd/handler.go
index cc221ca..55deb06 100644
--- a/fsd/handler.go
+++ b/fsd/handler.go
@@ -165,15 +165,17 @@ func (s *Server) handlePilotPosition(client *Client, packet []byte) {
 	client.lastUpdated.Store(time.Now())
 
 	// Check if we need to update the sendfast state
-	if client.sendFastEnabled {
-		if (client.closestVelocityClientDistance / 1852.0) > 5.0 { // 5.0 nautical miles
-			client.sendFastEnabled = false
-			sendDisableSendFastPacket(client)
-		}
-	} else {
-		if (client.closestVelocityClientDistance / 1852.0) < 5.0 { // 5.0 nautical miles
-			client.sendFastEnabled = true
-			sendEnableSendFastPacket(client)
+	if client.protoRevision == 101 {
+		if client.sendFastEnabled {
+			if (client.closestVelocityClientDistance / 1852.0) > 5.0 { // 5.0 nautical miles
+				client.sendFastEnabled = false
+				sendDisableSendFastPacket(client)
+			}
+		} else {
+			if (client.closestVelocityClientDistance / 1852.0) < 5.0 { // 5.0 nautical miles
+				client.sendFastEnabled = true
+				sendEnableSendFastPacket(client)
+			}
 		}
 	}
 }
diff --git a/fsd/postoffice.go b/fsd/postoffice.go
index 5b4d6c7..5441355 100644
--- a/fsd/postoffice.go
+++ b/fsd/postoffice.go
@@ -98,7 +98,7 @@ func (p *postOffice) search(client *Client, callback func(recipient *Client) boo
 			return true // Ignore self
 		}
 
-		if foundClient.protoRevision == 101 {
+		if !client.isAtc && client.protoRevision == 101 && foundClient.protoRevision == 101 {
 			clientLatLon := client.latLon()
 			foundClientLatLon := foundClient.latLon()
 			dist := distance(clientLatLon[0], clientLatLon[1], foundClientLatLon[0], foundClientLatLon[1])