From 8a2271218007e4af1a26c984fc7c7a142672f395 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@zdoom.fake>
Date: Sat, 30 Jan 2010 14:49:15 +0000
Subject: [PATCH] - fixed: Rocket trail particle positioning only worked when
 the rocket was moving.

SVN r2145 (trunk)
---
 src/p_effect.cpp | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/p_effect.cpp b/src/p_effect.cpp
index 8a4d5bb1f..0ecb53798 100644
--- a/src/p_effect.cpp
+++ b/src/p_effect.cpp
@@ -235,7 +235,18 @@ static void MakeFountain (AActor *actor, int color1, int color2)
 
 void P_RunEffect (AActor *actor, int effects)
 {
-	angle_t moveangle = R_PointToAngle2(0,0,actor->velx,actor->vely);
+	angle_t moveangle;
+	
+	// 512 is the limit below which R_PointToAngle2 does no longer returns usable values.
+	if (abs(actor->velx) > 512 || abs(actor->vely) > 512)
+	{
+		moveangle = R_PointToAngle2(0,0,actor->velx,actor->vely);
+	}
+	else
+	{
+		moveangle = actor->angle;
+	}
+
 	particle_t *particle;
 	int i;