Retrieve a small cone of blocks in the direction of the players veloc…

…ity.

This helps retrieving the right set of blocks when the player is falling,
traveling on cart, or in general traveling in a direction different from
the view direction.

src/clientiface.cpp

@@ -60,6 +60,24 @@ void RemoteClient::ResendBlockIfOnWire(v3s16 p)
 	}
 }
 
+LuaEntitySAO *getAttachedObject(PlayerSAO *sao, ServerEnvironment *env)
+{
+	if (!sao->isAttached())
+		return nullptr;
+
+	int id;
+	std::string bone;
+	v3f dummy;
+	sao->getAttachment(&id, &bone, &dummy, &dummy);
+	ServerActiveObject *ao = env->getActiveObject(id);
+	while (id && ao) {
+		ao->getAttachment(&id, &bone, &dummy, &dummy);
+		if (id)
+			ao = env->getActiveObject(id);
+	}
+	return dynamic_cast<LuaEntitySAO *>(ao);
+}
+
 void RemoteClient::GetNextBlocks (
 		ServerEnvironment *env,
 		EmergeManager * emerge,
@@ -91,7 +109,9 @@ void RemoteClient::GetNextBlocks (
 	}
 
 	v3f playerpos = sao->getBasePosition();
-	const v3f &playerspeed = player->getSpeed();
+	// if the player is attached, get the velocity from the attached object
+	LuaEntitySAO *lsao = getAttachedObject(sao, env);
+	const v3f &playerspeed = lsao? lsao->getVelocity() : player->getSpeed();
 	v3f playerspeeddir(0,0,0);
 	if(playerspeed.getLength() > 1.0*BS)
 		playerspeeddir = playerspeed / playerspeed.getLength();
@@ -170,11 +190,8 @@ void RemoteClient::GetNextBlocks (
 	s32 new_nearest_unsent_d = -1;
 
 	// get view range and camera fov from the client
-	s16 wanted_range = sao->getWantedRange();
+	s16 wanted_range = sao->getWantedRange() + 1;
 	float camera_fov = sao->getFov();
-	// if FOV, wanted_range are not available (old client), fall back to old default
-	if (wanted_range <= 0) wanted_range = 1000;
-	if (camera_fov <= 0) camera_fov = (72.0*M_PI/180) * 4./3.;
 
 	const s16 full_d_max = MYMIN(g_settings->getS16("max_block_send_distance"), wanted_range);
 	const s16 d_opt = MYMIN(g_settings->getS16("block_send_optimize_distance"), wanted_range);
@@ -185,7 +202,7 @@ void RemoteClient::GetNextBlocks (
 	s16 d_max_gen = MYMIN(g_settings->getS16("max_block_generate_distance"), wanted_range);
 
 	// Don't loop very much at a time
-	s16 max_d_increment_at_time = 2;
+	s16 max_d_increment_at_time = 1;
 	if(d_max > d_start + max_d_increment_at_time)
 		d_max = d_start + max_d_increment_at_time;
 
@@ -247,10 +264,16 @@ void RemoteClient::GetNextBlocks (
 				Don't generate or send if not in sight
 				FIXME This only works if the client uses a small enough
 				FOV setting. The default of 72 degrees is fine.
+				Also retrieve a smaller view cone in the direction of the player's
+				movement.
+				(0.1 is about 4 degrees)
 			*/
-
 			f32 dist;
-			if (!isBlockInSight(p, camera_pos, camera_dir, camera_fov, d_blocks_in_sight, &dist)) {
+			if (!(isBlockInSight(p, camera_pos, camera_dir, camera_fov,
+						d_blocks_in_sight, &dist) ||
+					(playerspeed.getLength() > 1.0f * BS &&
+					isBlockInSight(p, camera_pos, playerspeeddir, 0.1f,
+						d_blocks_in_sight)))) {
 				continue;
 			}