Make limiting of the reflow liquids queue size optional

If liquid_queue_purge_time == 0 then disable the queue size limiting and make this the default setting
Additionally, liquid_loop_max now defaults to 100000

minetest.conf.example

@@ -99,10 +99,11 @@
 # Enable a bit lower water surface; disable for speed (not quite optimized)
 #new_style_water = false
 # Max liquids processed per step
-#liquid_loop_max = 10000
+#liquid_loop_max = 100000
 # The time (in seconds) that the liquids queue may grow beyond processing
-# capacity until an attempt is made to decrease its size by dumping old queue items
+# capacity until an attempt is made to decrease its size by dumping old queue
-#liquid_queue_purge_time = 30
+# items.  A value of 0 disables the functionality.
+#liquid_queue_purge_time = 0
 # Update liquids every .. recommend for finite: 0.2
 #liquid_update = 1.0
 # Enable nice leaves; disable for speed

src/defaultsettings.cpp

@@ -276,8 +276,8 @@ void set_default_settings(Settings *settings)
 	settings->setDefault("movement_gravity", "9.81");
 
 	//liquid stuff
-	settings->setDefault("liquid_loop_max", "10000");
+	settings->setDefault("liquid_loop_max", "100000");
-	settings->setDefault("liquid_queue_purge_time", "30");
+	settings->setDefault("liquid_queue_purge_time", "0");
 	settings->setDefault("liquid_update", "1.0");
 
 	//mapgen stuff

src/map.cpp

@@ -1624,8 +1624,6 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 	u32 loopcount = 0;
 	u32 initial_size = m_transforming_liquid.size();
 
-	u32 curr_time = getTime(PRECISION_MILLI);
-
 	/*if(initial_size != 0)
 		infostream<<"transformLiquids(): initial_size="<<initial_size<<std::endl;*/
 
@@ -1638,11 +1636,11 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 	u32 liquid_loop_max = g_settings->getS32("liquid_loop_max");
 	u32 loop_max = liquid_loop_max;
 
-//	std::cout << "transformLiquids(): loopmax initial="
+#if 0
-//	           << loop_max * m_transforming_liquid_loop_count_multiplier;
 
-	// If liquid_loop_max is not keeping up with the queue size increase
+	/* If liquid_loop_max is not keeping up with the queue size increase
-	// loop_max up to a maximum of liquid_loop_max * dedicated_server_step.
+	 * loop_max up to a maximum of liquid_loop_max * dedicated_server_step.
+	 */
 	if (m_transforming_liquid.size() > loop_max * 2) {
 		// "Burst" mode
 		float server_step = g_settings->getFloat("dedicated_server_step");
@@ -1653,9 +1651,7 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 	}
 
 	loop_max *= m_transforming_liquid_loop_count_multiplier;
-
+#endif
-//	std::cout << " queue sz=" << m_transforming_liquid.size()
-//	           << " loop_max=" << loop_max;
 
 	while(m_transforming_liquid.size() != 0)
 	{
@@ -1913,9 +1909,17 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 	updateLighting(lighting_modified_blocks, modified_blocks);
 
 
-	/*
+	/* ----------------------------------------------------------------------
-	 * Queue size limiting
+	 * Manage the queue so that it does not grow indefinately
 	 */
+	u16 time_until_purge = g_settings->getU16("liquid_queue_purge_time");
+
+	if (time_until_purge == 0)
+		return; // Feature disabled
+
+	time_until_purge *= 1000;	// seconds -> milliseconds
+
+	u32 curr_time = getTime(PRECISION_MILLI);
 	u32 prev_unprocessed = m_unprocessed_count;
 	m_unprocessed_count = m_transforming_liquid.size();
 
@@ -1928,13 +1932,6 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 		m_queue_size_timer_started = true;
 	}
 
-	u16 time_until_purge = g_settings->getU16("liquid_queue_purge_time");
-	time_until_purge *= 1000;	// seconds -> milliseconds
-
-//	std::cout << " growing for: "
-//	           << (m_queue_size_timer_started ? curr_time - m_inc_trend_up_start_time : 0)
-//	           << "ms" << std::endl;
-
 	// Account for curr_time overflowing
 	if (m_queue_size_timer_started && m_inc_trending_up_start_time > curr_time)
 		m_queue_size_timer_started = false;