Use the correct variables in this function

Author: JohnAFernandez

code/network/multi_interpolate.cpp

@@ -179,9 +179,9 @@ void interpolation_manager::interpolate_main(vec3d* pos, matrix* ori, physics_in
 // correct the ship record for player ships when an up to date packet comes in.
 void interpolation_manager::reinterpolate_previous(TIMESTAMP stamp, int prev_packet_index, int next_packet_index,  vec3d* position, matrix* orientation, vec3d* velocity, vec3d* rotational_velocity)
 {
-	// calc what the current timing should be.
-	float numerator = static_cast<float>(_packets[_upcoming_packet_index].remote_missiontime) - static_cast<float>(stamp.value());
-	float denominator = static_cast<float>(_packets[_upcoming_packet_index].remote_missiontime) - static_cast<float>(_packets[_prev_packet_index].remote_missiontime);
+	// calc what the timing was previously.
+	float numerator = static_cast<float>(_packets[next_packet_index].remote_missiontime) - static_cast<float>(stamp.value());
+	float denominator = static_cast<float>(_packets[next_packet_index].remote_missiontime) - static_cast<float>(_packets[prev_packet_index].remote_missiontime);
 
 	denominator = (denominator > 0.05f) ? denominator : 0.05f;