X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Fmap.cpp;h=236972ae98a08751889f437e567e60709a2466f6;hb=b2102bfe49002f1ac10ca8288f5337e9feec7f65;hp=f128aff6c99d863f57069cf06d97ec4daa67d906;hpb=92833a07d111c55f61b23f66fd8aaa95f3239c33;p=minetest.git

diff --git a/src/map.cpp b/src/map.cpp
index f128aff6c..236972ae9 100644
--- a/src/map.cpp
+++ b/src/map.cpp
@@ -24,7 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "filesys.h"
 #include "voxel.h"
 #include "porting.h"
-#include "mapgen.h"
+#include "serialization.h"
 #include "nodemetadata.h"
 #include "settings.h"
 #include "log.h"
@@ -32,10 +32,23 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "nodedef.h"
 #include "gamedef.h"
 #include "util/directiontables.h"
+#include "util/mathconstants.h"
 #include "rollback_interface.h"
+#include "environment.h"
 #include "emerge.h"
 #include "mapgen_v6.h"
-#include "mapgen_indev.h"
+#include "biome.h"
+#include "config.h"
+#include "server.h"
+#include "database.h"
+#include "database-dummy.h"
+#include "database-sqlite3.h"
+#if USE_LEVELDB
+#include "database-leveldb.h"
+#endif
+#if USE_REDIS
+#include "database-redis.h"
+#endif
 
 #define PP(x) "("<<(x).X<<","<<(x).Y<<","<<(x).Z<<")"
 
@@ -65,8 +78,6 @@ Map::Map(std::ostream &dout, IGameDef *gamedef):
 	m_gamedef(gamedef),
 	m_sector_cache(NULL)
 {
-	/*m_sector_mutex.Init();
-	assert(m_sector_mutex.IsInitialized());*/
 }
 
 Map::~Map()
@@ -921,7 +932,8 @@ void Map::updateLighting(std::map<v3s16, MapBlock*> & a_blocks,
 /*
 */
 void Map::addNodeAndUpdate(v3s16 p, MapNode n,
-		std::map<v3s16, MapBlock*> &modified_blocks)
+		std::map<v3s16, MapBlock*> &modified_blocks,
+		bool remove_metadata)
 {
 	INodeDefManager *ndef = m_gamedef->ndef();
 
@@ -1008,8 +1020,9 @@ void Map::addNodeAndUpdate(v3s16 p, MapNode n,
 	/*
 		Remove node metadata
 	*/
-
-	removeNodeMetadata(p);
+	if (remove_metadata) {
+		removeNodeMetadata(p);
+	}
 
 	/*
 		Set the node on the map
@@ -1307,17 +1320,17 @@ void Map::removeNodeAndUpdate(v3s16 p,
 	}
 }
 
-bool Map::addNodeWithEvent(v3s16 p, MapNode n)
+bool Map::addNodeWithEvent(v3s16 p, MapNode n, bool remove_metadata)
 {
 	MapEditEvent event;
-	event.type = MEET_ADDNODE;
+	event.type = remove_metadata ? MEET_ADDNODE : MEET_SWAPNODE;
 	event.p = p;
 	event.n = n;
 
 	bool succeeded = true;
 	try{
 		std::map<v3s16, MapBlock*> modified_blocks;
-		addNodeAndUpdate(p, n, modified_blocks);
+		addNodeAndUpdate(p, n, modified_blocks, remove_metadata);
 
 		// Copy modified_blocks to event
 		for(std::map<v3s16, MapBlock*>::iterator
@@ -1460,11 +1473,11 @@ void Map::timerUpdate(float dtime, float unload_timeout,
 				v3s16 p = block->getPos();
 
 				// Save if modified
-				if(block->getModified() != MOD_STATE_CLEAN
-						&& save_before_unloading)
+				if (block->getModified() != MOD_STATE_CLEAN && save_before_unloading)
 				{
 					modprofiler.add(block->getModifiedReason(), 1);
-					saveBlock(block);
+					if (!saveBlock(block))
+						continue;
 					saved_blocks_count++;
 				}
 
@@ -1604,7 +1617,6 @@ struct NodeNeighbor {
 	NeighborType t;
 	v3s16 p;
 	bool l; //can liquid
-	bool i; //infinity
 };
 
 void Map::transforming_liquid_add(v3s16 p) {
@@ -1615,376 +1627,8 @@ s32 Map::transforming_liquid_size() {
         return m_transforming_liquid.size();
 }
 
-const v3s16 g_7dirs[7] =
-{
-	// +right, +top, +back
-	v3s16( 0,-1, 0), // bottom
-	v3s16( 0, 0, 0), // self
-	v3s16( 0, 0, 1), // back
-	v3s16( 0, 0,-1), // front
-	v3s16( 1, 0, 0), // right
-	v3s16(-1, 0, 0), // left
-	v3s16( 0, 1, 0)  // top
-};
-
-#define D_BOTTOM 0
-#define D_TOP 6
-#define D_SELF 1
-
-void Map::transformLiquidsFinite(std::map<v3s16, MapBlock*> & modified_blocks)
-{
-	INodeDefManager *nodemgr = m_gamedef->ndef();
-
-	DSTACK(__FUNCTION_NAME);
-	//TimeTaker timer("transformLiquids()");
-
-	u32 loopcount = 0;
-	u32 initial_size = m_transforming_liquid.size();
-
-	u8 relax = g_settings->getS16("liquid_relax");
-	bool fast_flood = g_settings->getS16("liquid_fast_flood");
-	int water_level = g_settings->getS16("water_level");
-
-	// list of nodes that due to viscosity have not reached their max level height
-	UniqueQueue<v3s16> must_reflow, must_reflow_second;
-
-	// List of MapBlocks that will require a lighting update (due to lava)
-	std::map<v3s16, MapBlock*> lighting_modified_blocks;
-
-	u16 loop_max = g_settings->getU16("liquid_loop_max");
-
-	//if (m_transforming_liquid.size() > 0) errorstream << "Liquid queue size="<<m_transforming_liquid.size()<<std::endl;
-
-	while (m_transforming_liquid.size() > 0)
-	{
-		// This should be done here so that it is done when continue is used
-		if (loopcount >= initial_size || loopcount >= loop_max)
-			break;
-		loopcount++;
-		/*
-			Get a queued transforming liquid node
-		*/
-		v3s16 p0 = m_transforming_liquid.pop_front();
-		u16 total_level = 0;
-		// surrounding flowing liquid nodes
-		NodeNeighbor neighbors[7]; 
-		// current level of every block
-		s8 liquid_levels[7] = {-1, -1, -1, -1, -1, -1, -1};
-		 // target levels
-		s8 liquid_levels_want[7] = {-1, -1, -1, -1, -1, -1, -1};
-		s8 can_liquid_same_level = 0;
-		content_t liquid_kind = CONTENT_IGNORE;
-		content_t liquid_kind_flowing = CONTENT_IGNORE;
-		/*
-			Collect information about the environment
-		 */
-		const v3s16 *dirs = g_7dirs;
-		for (u16 i = 0; i < 7; i++) {
-			NeighborType nt = NEIGHBOR_SAME_LEVEL;
-			switch (i) {
-				case D_TOP:
-					nt = NEIGHBOR_UPPER;
-					break;
-				case D_BOTTOM:
-					nt = NEIGHBOR_LOWER;
-					break;
-			}
-			v3s16 npos = p0 + dirs[i];
-
-			neighbors[i].n = getNodeNoEx(npos);
-			neighbors[i].t = nt;
-			neighbors[i].p = npos;
-			neighbors[i].l = 0;
-			neighbors[i].i = 0;
-			NodeNeighbor & nb = neighbors[i];
-
-			switch (nodemgr->get(nb.n.getContent()).liquid_type) {
-				case LIQUID_NONE:
-					if (nb.n.getContent() == CONTENT_AIR) {
-						liquid_levels[i] = 0;
-						nb.l = 1;
-					}
-					break;
-				case LIQUID_SOURCE:
-					// if this node is not (yet) of a liquid type,
-					// choose the first liquid type we encounter
-					if (liquid_kind_flowing == CONTENT_IGNORE)
-						liquid_kind_flowing = nodemgr->getId(
-							nodemgr->get(nb.n).liquid_alternative_flowing);
-					if (liquid_kind == CONTENT_IGNORE)
-						liquid_kind = nb.n.getContent();
-					if (nb.n.getContent() == liquid_kind) {
-						liquid_levels[i] = LIQUID_LEVEL_SOURCE;
-						nb.l = 1;
-						nb.i = (nb.n.param2 & LIQUID_INFINITY_MASK);
-					}
-					break;
-				case LIQUID_FLOWING:
-					// if this node is not (yet) of a liquid type,
-					// choose the first liquid type we encounter
-					if (liquid_kind_flowing == CONTENT_IGNORE)
-						liquid_kind_flowing = nb.n.getContent();
-					if (liquid_kind == CONTENT_IGNORE)
-						liquid_kind = nodemgr->getId(
-							nodemgr->get(nb.n).liquid_alternative_source);
-					if (nb.n.getContent() == liquid_kind_flowing) {
-						liquid_levels[i] = (nb.n.param2 & LIQUID_LEVEL_MASK);
-						nb.l = 1;
-					}
-					break;
-			}
-			
-			if (nb.l && nb.t == NEIGHBOR_SAME_LEVEL)
-				++can_liquid_same_level;
-			if (liquid_levels[i] > 0)
-				total_level += liquid_levels[i];
-
-			/*
-			infostream << "get node i=" <<(int)i<<" " << PP(npos) << " c="
-			<< nb.n.getContent() <<" p0="<< (int)nb.n.param0 <<" p1="
-			<< (int)nb.n.param1 <<" p2="<< (int)nb.n.param2 << " lt="
-			<< nodemgr->get(nb.n.getContent()).liquid_type
-			//<< " lk=" << liquid_kind << " lkf=" << liquid_kind_flowing
-			<< " l="<< nb.l	<< " inf="<< nb.i << " nlevel=" << (int)liquid_levels[i]
-			<< " tlevel=" << (int)total_level << " cansame="
-			<< (int)can_liquid_same_level << std::endl;
-			*/
-		}
-
-		if (liquid_kind == CONTENT_IGNORE ||
-			!neighbors[D_SELF].l ||
-			total_level <= 0)
-			continue;
-
-		// fill bottom block
-		if (neighbors[D_BOTTOM].l) {
-			liquid_levels_want[D_BOTTOM] = total_level > LIQUID_LEVEL_SOURCE ?
-				LIQUID_LEVEL_SOURCE : total_level;
-			total_level -= liquid_levels_want[D_BOTTOM];
-		}
-
-		//relax up
-		if (relax && ((p0.Y == water_level) || (fast_flood && p0.Y <= water_level)) && liquid_levels[D_TOP] == 0 &&
-			liquid_levels[D_BOTTOM] == LIQUID_LEVEL_SOURCE &&
-			total_level >= LIQUID_LEVEL_SOURCE * can_liquid_same_level-
-			(can_liquid_same_level - relax) &&
-			can_liquid_same_level >= relax + 1) { 
-			total_level = LIQUID_LEVEL_SOURCE * can_liquid_same_level; 
-		}
-
-		// prevent lakes in air above unloaded blocks
-		if (liquid_levels[D_TOP] == 0 && (p0.Y > water_level) && neighbors[D_BOTTOM].n.getContent() == CONTENT_IGNORE && !(loopcount % 3)) {
-			--total_level;
-		}
-
-		// calculate self level 5 blocks
-		u8 want_level = 
-			  total_level >= LIQUID_LEVEL_SOURCE * can_liquid_same_level
-			? LIQUID_LEVEL_SOURCE 
-			: total_level / can_liquid_same_level;
-		total_level -= want_level * can_liquid_same_level;
-
-		//relax down
-		if (relax && p0.Y == water_level + 1 && liquid_levels[D_TOP] == 0 &&
-			liquid_levels[D_BOTTOM] == LIQUID_LEVEL_SOURCE && want_level == 0 &&
-			total_level <= (can_liquid_same_level - relax) &&
-			can_liquid_same_level >= relax + 1) {
-			total_level = 0;
-		}
-
-		for (u16 ii = D_SELF; ii < D_TOP; ++ii) { // fill only same level
-			if (!neighbors[ii].l)
-				continue;
-			liquid_levels_want[ii] = want_level;
-			if (liquid_levels_want[ii] < LIQUID_LEVEL_SOURCE && total_level > 0) {
-				if (loopcount % 3 || liquid_levels[ii] <= 0){
-					if (liquid_levels[ii] > liquid_levels_want[ii]) {
-						++liquid_levels_want[ii];
-						--total_level;
-					}
-				} else if (neighbors[ii].l > 0){
-						++liquid_levels_want[ii];
-						--total_level;
-				}
-			}
-		}
-
-		for (u16 ii = 0; ii < 7; ++ii) {
-			if (total_level < 1) break;
-			if (liquid_levels_want[ii] >= 0 &&
-				liquid_levels_want[ii] < LIQUID_LEVEL_SOURCE) {
-				++liquid_levels_want[ii];
-				--total_level;
-			}
-		}
-
-		// fill top block if can
-		if (neighbors[D_TOP].l) {
-			liquid_levels_want[D_TOP] = total_level > LIQUID_LEVEL_SOURCE ?
-				LIQUID_LEVEL_SOURCE : total_level;
-			total_level -= liquid_levels_want[D_TOP];
-		}
-
-		for (u16 ii = 0; ii < 7; ii++) // infinity and cave flood optimization
-			if (    neighbors[ii].i ||
-				(liquid_levels_want[ii] >= 0 &&
-				 (fast_flood && p0.Y < water_level &&
-				  (initial_size >= 1000
-				   && ii != D_TOP
-				   && want_level >= LIQUID_LEVEL_SOURCE/4
-				   && can_liquid_same_level >= 5
-				   && liquid_levels[D_TOP] >= LIQUID_LEVEL_SOURCE))))
-				liquid_levels_want[ii] = LIQUID_LEVEL_SOURCE;
-
-		/*
-		if (total_level > 0) //|| flowed != volume)
-			infostream <<" AFTER level=" << (int)total_level 
-			//<< " flowed="<<flowed<< " volume=" << volume
-			<< " wantsame="<<(int)want_level<< " top="
-			<< (int)liquid_levels_want[D_TOP]<< " topwas="
-			<< (int)liquid_levels[D_TOP]<< " bot="
-			<< (int)liquid_levels_want[D_BOTTOM]<<std::endl;
-		*/
-
-		u8 changed = 0;
-		for (u16 i = 0; i < 7; i++) {
-			if (liquid_levels_want[i] < 0 || !neighbors[i].l) 
-				continue;
-			MapNode & n0 = neighbors[i].n;
-			p0 = neighbors[i].p;
-			/*
-				decide on the type (and possibly level) of the current node
-			*/
-			content_t new_node_content;
-			s8 new_node_level = -1;
-			u8 viscosity = nodemgr->get(liquid_kind).liquid_viscosity;
-			if (viscosity > 1 && liquid_levels_want[i] != liquid_levels[i]) {
-				// amount to gain, limited by viscosity
-				// must be at least 1 in absolute value
-				s8 level_inc = liquid_levels_want[i] - liquid_levels[i];
-				if (level_inc < -viscosity || level_inc > viscosity)
-					new_node_level = liquid_levels[i] + level_inc/viscosity;
-				else if (level_inc < 0)
-					new_node_level = liquid_levels[i] - 1;
-				else if (level_inc > 0)
-					new_node_level = liquid_levels[i] + 1;
-			} else {
-				new_node_level = liquid_levels_want[i];
-			}
-			
-			if (new_node_level >= LIQUID_LEVEL_SOURCE)
-				new_node_content = liquid_kind;
-			else if (new_node_level > 0)
-				new_node_content = liquid_kind_flowing;
-			else
-				new_node_content = CONTENT_AIR;
-
-			// last level must flow down on stairs
-			if (liquid_levels_want[i] != liquid_levels[i] &&
-				liquid_levels[D_TOP] <= 0 && !neighbors[D_BOTTOM].l &&
-				new_node_level >= 1 && new_node_level <= 2) {
-				for (u16 ii = D_SELF + 1; ii < D_TOP; ++ii) { // only same level
-					if (neighbors[ii].l)
-						must_reflow_second.push_back(p0 + dirs[ii]);
-				}
-			}
-
-			/*
-				check if anything has changed.
-				if not, just continue with the next node.
-			 */
-			if (
-				 new_node_content == n0.getContent() 
-				&& (nodemgr->get(n0.getContent()).liquid_type != LIQUID_FLOWING ||
-				 ((n0.param2 & LIQUID_LEVEL_MASK) == (u8)new_node_level 
-				 //&& ((n0.param2 & LIQUID_FLOW_DOWN_MASK) ==
-				 //LIQUID_FLOW_DOWN_MASK) == flowing_down
-				 ))
-				&&
-				 (nodemgr->get(n0.getContent()).liquid_type != LIQUID_SOURCE ||
-				 (((n0.param2 & LIQUID_INFINITY_MASK) ==
-					LIQUID_INFINITY_MASK) == neighbors[i].i
-				 ))
-			   ) {
-				continue;
-			}
-			++changed;
-
-			/*
-				update the current node
-			 */
-			if (nodemgr->get(new_node_content).liquid_type == LIQUID_FLOWING) {
-				// set level to last 3 bits, flowing down bit to 4th bit
-				n0.param2 = (new_node_level & LIQUID_LEVEL_MASK);
-			} else if (nodemgr->get(new_node_content).liquid_type == LIQUID_SOURCE) {
-				//n0.param2 = ~(LIQUID_LEVEL_MASK | LIQUID_FLOW_DOWN_MASK);
-				n0.param2 = (neighbors[i].i ? LIQUID_INFINITY_MASK : 0x00);
-			}
-			/*
-			infostream << "set node i=" <<(int)i<<" "<< PP(p0)<< " nc="
-			<<new_node_content<< " p2="<<(int)n0.param2<< " nl="
-			<<(int)new_node_level<<std::endl;
-			*/
-			
-			n0.setContent(new_node_content);
-			// Find out whether there is a suspect for this action
-			std::string suspect;
-			if(m_gamedef->rollback()){
-				suspect = m_gamedef->rollback()->getSuspect(p0, 83, 1);
-			}
-
-			if(!suspect.empty()){
-				// Blame suspect
-				RollbackScopeActor rollback_scope(m_gamedef->rollback(), suspect, true);
-				// Get old node for rollback
-				RollbackNode rollback_oldnode(this, p0, m_gamedef);
-				// Set node
-				setNode(p0, n0);
-				// Report
-				RollbackNode rollback_newnode(this, p0, m_gamedef);
-				RollbackAction action;
-				action.setSetNode(p0, rollback_oldnode, rollback_newnode);
-				m_gamedef->rollback()->reportAction(action);
-			} else {
-				// Set node
-				setNode(p0, n0);
-			}
-
-			v3s16 blockpos = getNodeBlockPos(p0);
-			MapBlock *block = getBlockNoCreateNoEx(blockpos);
-			if(block != NULL) {
-				modified_blocks[blockpos] = block;
-				// If node emits light, MapBlock requires lighting update
-				if(nodemgr->get(n0).light_source != 0)
-					lighting_modified_blocks[block->getPos()] = block;
-			}
-			must_reflow.push_back(neighbors[i].p);
-		}
-		/* //for better relax  only same level
-		if (changed)  for (u16 ii = D_SELF + 1; ii < D_TOP; ++ii) {
-			if (!neighbors[ii].l) continue;
-			must_reflow.push_back(p0 + dirs[ii]);
-		}*/
-	}
-	/*
-	if (loopcount)
-		infostream<<"Map::transformLiquids(): loopcount="<<loopcount
-		<<" reflow="<<must_reflow.size()
-		<<" queue="<< m_transforming_liquid.size()<<std::endl;
-	*/
-	while (must_reflow.size() > 0)
-		m_transforming_liquid.push_back(must_reflow.pop_front());
-	while (must_reflow_second.size() > 0)
-		m_transforming_liquid.push_back(must_reflow_second.pop_front());
-	updateLighting(lighting_modified_blocks, modified_blocks);
-}
-
 void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 {
-
-	if (g_settings->getBool("liquid_finite"))
-		return Map::transformLiquidsFinite(modified_blocks);
-
 	INodeDefManager *nodemgr = m_gamedef->ndef();
 
 	DSTACK(__FUNCTION_NAME);
@@ -2117,6 +1761,7 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 		content_t new_node_content;
 		s8 new_node_level = -1;
 		s8 max_node_level = -1;
+		u8 range = rangelim(nodemgr->get(liquid_kind).liquid_range, 0, LIQUID_LEVEL_MAX+1);
 		if ((num_sources >= 2 && nodemgr->get(liquid_kind).liquid_renewable) || liquid_type == LIQUID_SOURCE) {
 			// liquid_kind will be set to either the flowing alternative of the node (if it's a liquid)
 			// or the flowing alternative of the first of the surrounding sources (if it's air), so
@@ -2126,6 +1771,8 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 			// liquid_kind is set properly, see above
 			new_node_content = liquid_kind;
 			max_node_level = new_node_level = LIQUID_LEVEL_MAX;
+			if (new_node_level < (LIQUID_LEVEL_MAX+1-range))
+				new_node_content = CONTENT_AIR;
 		} else {
 			// no surrounding sources, so get the maximum level that can flow into this node
 			for (u16 i = 0; i < num_flows; i++) {
@@ -2166,7 +1813,7 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 			} else
 				new_node_level = max_node_level;
 
-			if (new_node_level >= 0)
+			if (max_node_level >= (LIQUID_LEVEL_MAX+1-range))
 				new_node_content = liquid_kind;
 			else
 				new_node_content = CONTENT_AIR;
@@ -2186,6 +1833,7 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 		/*
 			update the current node
 		 */
+		MapNode n00 = n0;
 		//bool flow_down_enabled = (flowing_down && ((n0.param2 & LIQUID_FLOW_DOWN_MASK) != LIQUID_FLOW_DOWN_MASK));
 		if (nodemgr->get(new_node_content).liquid_type == LIQUID_FLOWING) {
 			// set level to last 3 bits, flowing down bit to 4th bit
@@ -2223,8 +1871,9 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 		MapBlock *block = getBlockNoCreateNoEx(blockpos);
 		if(block != NULL) {
 			modified_blocks[blockpos] =  block;
-			// If node emits light, MapBlock requires lighting update
-			if(nodemgr->get(n0).light_source != 0)
+			// If new or old node emits light, MapBlock requires lighting update
+			if(nodemgr->get(n0).light_source != 0 ||
+					nodemgr->get(n00).light_source != 0)
 				lighting_modified_blocks[block->getPos()] = block;
 		}
 
@@ -2255,7 +1904,7 @@ void Map::transformLiquids(std::map<v3s16, MapBlock*> & modified_blocks)
 	updateLighting(lighting_modified_blocks, modified_blocks);
 }
 
-NodeMetadata* Map::getNodeMetadata(v3s16 p)
+NodeMetadata *Map::getNodeMetadata(v3s16 p)
 {
 	v3s16 blockpos = getNodeBlockPos(p);
 	v3s16 p_rel = p - blockpos*MAP_BLOCKSIZE;
@@ -2265,8 +1914,7 @@ NodeMetadata* Map::getNodeMetadata(v3s16 p)
 				<<PP(blockpos)<<std::endl;
 		block = emergeBlock(blockpos, false);
 	}
-	if(!block)
-	{
+	if(!block){
 		infostream<<"WARNING: Map::getNodeMetadata(): Block not found"
 				<<std::endl;
 		return NULL;
@@ -2275,7 +1923,7 @@ NodeMetadata* Map::getNodeMetadata(v3s16 p)
 	return meta;
 }
 
-void Map::setNodeMetadata(v3s16 p, NodeMetadata *meta)
+bool Map::setNodeMetadata(v3s16 p, NodeMetadata *meta)
 {
 	v3s16 blockpos = getNodeBlockPos(p);
 	v3s16 p_rel = p - blockpos*MAP_BLOCKSIZE;
@@ -2285,13 +1933,13 @@ void Map::setNodeMetadata(v3s16 p, NodeMetadata *meta)
 				<<PP(blockpos)<<std::endl;
 		block = emergeBlock(blockpos, false);
 	}
-	if(!block)
-	{
+	if(!block){
 		infostream<<"WARNING: Map::setNodeMetadata(): Block not found"
 				<<std::endl;
-		return;
+		return false;
 	}
 	block->m_node_metadata.set(p_rel, meta);
+	return true;
 }
 
 void Map::removeNodeMetadata(v3s16 p)
@@ -2318,8 +1966,7 @@ NodeTimer Map::getNodeTimer(v3s16 p)
 				<<PP(blockpos)<<std::endl;
 		block = emergeBlock(blockpos, false);
 	}
-	if(!block)
-	{
+	if(!block){
 		infostream<<"WARNING: Map::getNodeTimer(): Block not found"
 				<<std::endl;
 		return NodeTimer();
@@ -2338,8 +1985,7 @@ void Map::setNodeTimer(v3s16 p, NodeTimer t)
 				<<PP(blockpos)<<std::endl;
 		block = emergeBlock(blockpos, false);
 	}
-	if(!block)
-	{
+	if(!block){
 		infostream<<"WARNING: Map::setNodeTimer(): Block not found"
 				<<std::endl;
 		return;
@@ -2366,41 +2012,41 @@ void Map::removeNodeTimer(v3s16 p)
 */
 ServerMap::ServerMap(std::string savedir, IGameDef *gamedef, EmergeManager *emerge):
 	Map(dout_server, gamedef),
-	m_seed(0),
-	m_map_metadata_changed(true),
-	m_database(NULL),
-	m_database_read(NULL),
-	m_database_write(NULL)
+	m_emerge(emerge),
+	m_map_metadata_changed(true)
 {
 	verbosestream<<__FUNCTION_NAME<<std::endl;
 
-	m_emerge = emerge;
-	m_mgparams = m_emerge->getParamsFromSettings(g_settings);
-	if (!m_mgparams)
-		m_mgparams = new MapgenV6Params();
-
-	m_seed = m_mgparams->seed;
-
-	if (g_settings->get("fixed_map_seed").empty())
-	{
-		m_seed = (((u64)(myrand() & 0xffff) << 0)
-				| ((u64)(myrand() & 0xffff) << 16)
-				| ((u64)(myrand() & 0xffff) << 32)
-				| ((u64)(myrand() & 0xffff) << 48));
-		m_mgparams->seed = m_seed;
-	}
-
 	/*
-		Experimental and debug stuff
+		Try to load map; if not found, create a new one.
 	*/
 
-	{
+	// Determine which database backend to use
+	std::string conf_path = savedir + DIR_DELIM + "world.mt";
+	Settings conf;
+	bool succeeded = conf.readConfigFile(conf_path.c_str());
+	if (!succeeded || !conf.exists("backend")) {
+		// fall back to sqlite3
+		dbase = new Database_SQLite3(this, savedir);
+		conf.set("backend", "sqlite3");
+	} else {
+		std::string backend = conf.get("backend");
+		if (backend == "dummy")
+			dbase = new Database_Dummy(this);
+		else if (backend == "sqlite3")
+			dbase = new Database_SQLite3(this, savedir);
+		#if USE_LEVELDB
+		else if (backend == "leveldb")
+			dbase = new Database_LevelDB(this, savedir);
+		#endif
+		#if USE_REDIS
+		else if (backend == "redis")
+			dbase = new Database_Redis(this, savedir);
+		#endif
+		else
+			throw BaseException("Unknown map backend");
 	}
 
-	/*
-		Try to load map; if not found, create a new one.
-	*/
-
 	m_savedir = savedir;
 	m_map_saving_enabled = false;
 
@@ -2436,7 +2082,7 @@ ServerMap::ServerMap(std::string savedir, IGameDef *gamedef, EmergeManager *emer
 				infostream<<"ServerMap: Successfully loaded map "
 						<<"metadata from "<<savedir
 						<<", assuming valid save directory."
-						<<" seed="<<m_seed<<"."
+						<<" seed="<< m_emerge->params.seed <<"."
 						<<std::endl;
 
 				m_map_saving_enabled = true;
@@ -2492,12 +2138,7 @@ ServerMap::~ServerMap()
 	/*
 		Close database if it was opened
 	*/
-	if(m_database_read)
-		sqlite3_finalize(m_database_read);
-	if(m_database_write)
-		sqlite3_finalize(m_database_write);
-	if(m_database)
-		sqlite3_close(m_database);
+	delete dbase;
 
 #if 0
 	/*
@@ -2510,8 +2151,16 @@ ServerMap::~ServerMap()
 		delete chunk;
 	}
 #endif
+}
 
-	delete m_mgparams;
+u64 ServerMap::getSeed()
+{
+	return m_emerge->params.seed;
+}
+
+s16 ServerMap::getWaterLevel()
+{
+	return m_emerge->params.water_level;
 }
 
 bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
@@ -2519,7 +2168,7 @@ bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
 	bool enable_mapgen_debug_info = m_emerge->mapgen_debug_info;
 	EMERGE_DBG_OUT("initBlockMake(): " PP(blockpos) " - " PP(blockpos));
 
-	s16 chunksize = m_mgparams->chunksize;
+	s16 chunksize = m_emerge->params.chunksize;
 	s16 coffset = -chunksize / 2;
 	v3s16 chunk_offset(coffset, coffset, coffset);
 	v3s16 blockpos_div = getContainerPos(blockpos - chunk_offset, chunksize);
@@ -2535,7 +2184,7 @@ bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
 		blockpos_over_limit(blockpos_max + extra_borders))
 		return false;
 
-	data->seed = m_seed;
+	data->seed = m_emerge->params.seed;
 	data->blockpos_min = blockpos_min;
 	data->blockpos_max = blockpos_max;
 	data->blockpos_requested = blockpos;
@@ -2556,6 +2205,7 @@ bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
 			// Sector metadata is loaded from disk if not already loaded.
 			ServerMapSector *sector = createSector(sectorpos);
 			assert(sector);
+			(void) sector;
 
 			for(s16 y=blockpos_min.Y-extra_borders.Y;
 					y<=blockpos_max.Y+extra_borders.Y; y++)
@@ -2605,7 +2255,7 @@ bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
 		//TimeTaker timer("initBlockMake() initialEmerge");
 		data->vmanip->initialEmerge(bigarea_blocks_min, bigarea_blocks_max, false);
 	}
-	
+
 	// Ensure none of the blocks to be generated were marked as containing CONTENT_IGNORE
 /*	for (s16 z = blockpos_min.Z; z <= blockpos_max.Z; z++) {
 		for (s16 y = blockpos_min.Y; y <= blockpos_max.Y; y++) {
@@ -2625,7 +2275,7 @@ bool ServerMap::initBlockMake(BlockMakeData *data, v3s16 blockpos)
 	return true;
 }
 
-MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
+void ServerMap::finishBlockMake(BlockMakeData *data,
 		std::map<v3s16, MapBlock*> &changed_blocks)
 {
 	v3s16 blockpos_min = data->blockpos_min;
@@ -2719,7 +2369,9 @@ MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
 				y<=blockpos_max.Y+extra_borders.Y; y++)
 		{
 			v3s16 p(x, y, z);
-			getBlockNoCreateNoEx(p)->setLightingExpired(false);
+			MapBlock * block = getBlockNoCreateNoEx(p);
+			if (block != NULL)
+				block->setLightingExpired(false);
 		}
 
 #if 0
@@ -2735,7 +2387,8 @@ MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
 			i != changed_blocks.end(); ++i)
 	{
 		MapBlock *block = i->second;
-		assert(block);
+		if (!block)
+			continue;
 		/*
 			Update day/night difference cache of the MapBlocks
 		*/
@@ -2756,7 +2409,8 @@ MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
 	{
 		v3s16 p(x, y, z);
 		MapBlock *block = getBlockNoCreateNoEx(p);
-		assert(block);
+		if (!block)
+			continue;
 		block->setGenerated(true);
 	}
 
@@ -2769,6 +2423,8 @@ MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
 	/*infostream<<"finishBlockMake() done for ("<<blockpos_requested.X
 			<<","<<blockpos_requested.Y<<","
 			<<blockpos_requested.Z<<")"<<std::endl;*/
+
+
 #if 0
 	if(enable_mapgen_debug_info)
 	{
@@ -2792,10 +2448,7 @@ MapBlock* ServerMap::finishBlockMake(BlockMakeData *data,
 	}
 #endif
 
-	MapBlock *block = getBlockNoCreateNoEx(blockpos_requested);
-	assert(block);
-
-	return block;
+	getBlockNoCreateNoEx(blockpos_requested);
 }
 
 ServerMapSector * ServerMap::createSector(v2s16 p2d)
@@ -3061,7 +2714,9 @@ MapBlock * ServerMap::emergeBlock(v3s16 p, bool create_blank)
 
 		return block;
 	}
-	/*if(allow_generate)
+
+#if 0
+	if(allow_generate)
 	{
 		std::map<v3s16, MapBlock*> modified_blocks;
 		MapBlock *block = generateBlock(p, modified_blocks);
@@ -3084,11 +2739,46 @@ MapBlock * ServerMap::emergeBlock(v3s16 p, bool create_blank)
 
 			return block;
 		}
-	}*/
+	}
+#endif
 
 	return NULL;
 }
 
+MapBlock *ServerMap::getBlockOrEmerge(v3s16 p3d)
+{
+	MapBlock *block = getBlockNoCreateNoEx(p3d);
+	if (block == NULL)
+		m_emerge->enqueueBlockEmerge(PEER_ID_INEXISTENT, p3d, false);
+
+	return block;
+}
+
+void ServerMap::prepareBlock(MapBlock *block) {
+}
+
+// N.B.  This requires no synchronization, since data will not be modified unless
+// the VoxelManipulator being updated belongs to the same thread.
+void ServerMap::updateVManip(v3s16 pos)
+{
+	Mapgen *mg = m_emerge->getCurrentMapgen();
+	if (!mg)
+		return;
+
+	ManualMapVoxelManipulator *vm = mg->vm;
+	if (!vm)
+		return;
+
+	if (!vm->m_area.contains(pos))
+		return;
+
+	s32 idx = vm->m_area.index(pos);
+	vm->m_data[idx] = getNodeNoEx(pos);
+	vm->m_flags[idx] &= ~VOXELFLAG_NO_DATA;
+
+	vm->m_is_dirty = true;
+}
+
 s16 ServerMap::findGroundLevel(v2s16 p2d)
 {
 #if 0
@@ -3133,81 +2823,12 @@ s16 ServerMap::findGroundLevel(v2s16 p2d)
 	//return (s16)level;
 }
 
-void ServerMap::createDatabase() {
-	int e;
-	assert(m_database);
-	e = sqlite3_exec(m_database,
-		"CREATE TABLE IF NOT EXISTS `blocks` ("
-			"`pos` INT NOT NULL PRIMARY KEY,"
-			"`data` BLOB"
-		");"
-	, NULL, NULL, NULL);
-	if(e == SQLITE_ABORT)
-		throw FileNotGoodException("Could not create database structure");
-	else
-		infostream<<"ServerMap: Database structure was created";
-}
-
-void ServerMap::verifyDatabase() {
-	if(m_database)
-		return;
-
-	{
-		std::string dbp = m_savedir + DIR_DELIM + "map.sqlite";
-		bool needs_create = false;
-		int d;
-
-		/*
-			Open the database connection
-		*/
-
-		createDirs(m_savedir);
-
-		if(!fs::PathExists(dbp))
-			needs_create = true;
-
-		d = sqlite3_open_v2(dbp.c_str(), &m_database, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
-		if(d != SQLITE_OK) {
-			infostream<<"WARNING: Database failed to open: "<<sqlite3_errmsg(m_database)<<std::endl;
-			throw FileNotGoodException("Cannot open database file");
-		}
-
-		if(needs_create)
-			createDatabase();
-
-		d = sqlite3_prepare(m_database, "SELECT `data` FROM `blocks` WHERE `pos`=? LIMIT 1", -1, &m_database_read, NULL);
-		if(d != SQLITE_OK) {
-			infostream<<"WARNING: Database read statment failed to prepare: "<<sqlite3_errmsg(m_database)<<std::endl;
-			throw FileNotGoodException("Cannot prepare read statement");
-		}
-
-		d = sqlite3_prepare(m_database, "REPLACE INTO `blocks` VALUES(?, ?)", -1, &m_database_write, NULL);
-		if(d != SQLITE_OK) {
-			infostream<<"WARNING: Database write statment failed to prepare: "<<sqlite3_errmsg(m_database)<<std::endl;
-			throw FileNotGoodException("Cannot prepare write statement");
-		}
-
-		d = sqlite3_prepare(m_database, "SELECT `pos` FROM `blocks`", -1, &m_database_list, NULL);
-		if(d != SQLITE_OK) {
-			infostream<<"WARNING: Database list statment failed to prepare: "<<sqlite3_errmsg(m_database)<<std::endl;
-			throw FileNotGoodException("Cannot prepare read statement");
-		}
-
-		infostream<<"ServerMap: Database opened"<<std::endl;
-	}
-}
-
 bool ServerMap::loadFromFolders() {
-	if(!m_database && !fs::PathExists(m_savedir + DIR_DELIM + "map.sqlite"))
+	if(!dbase->Initialized() && !fs::PathExists(m_savedir + DIR_DELIM + "map.sqlite")) // ?
 		return true;
 	return false;
 }
 
-sqlite3_int64 ServerMap::getBlockAsInteger(const v3s16 pos) {
-	return (sqlite3_int64)pos.Z*16777216 +
-		(sqlite3_int64)pos.Y*4096 + (sqlite3_int64)pos.X;
-}
-
 void ServerMap::createDirs(std::string path)
 {
 	if(fs::CreateAllDirs(path) == false)
@@ -3237,12 +2858,13 @@ std::string ServerMap::getSectorDir(v2s16 pos, int layout)
 			return m_savedir + DIR_DELIM + "sectors2" + DIR_DELIM + cc;
 		default:
 			assert(false);
+			return "";
 	}
 }
 
 v2s16 ServerMap::getSectorPos(std::string dirname)
 {
-	unsigned int x, y;
+	unsigned int x = 0, y = 0;
 	int r;
 	std::string component;
 	fs::RemoveLastPathComponent(dirname, &component, 1);
@@ -3380,50 +3002,13 @@ void ServerMap::save(ModifiedState save_level)
 	}
 }
 
-static s32 unsignedToSigned(s32 i, s32 max_positive)
-{
-	if(i < max_positive)
-		return i;
-	else
-		return i - 2*max_positive;
-}
-
-// modulo of a negative number does not work consistently in C
-static sqlite3_int64 pythonmodulo(sqlite3_int64 i, sqlite3_int64 mod)
-{
-	if(i >= 0)
-		return i % mod;
-	return mod - ((-i) % mod);
-}
-
-v3s16 ServerMap::getIntegerAsBlock(sqlite3_int64 i)
-{
-	s32 x = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-	i = (i - x) / 4096;
-	s32 y = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-	i = (i - y) / 4096;
-	s32 z = unsignedToSigned(pythonmodulo(i, 4096), 2048);
-	return v3s16(x,y,z);
-}
-
 void ServerMap::listAllLoadableBlocks(std::list<v3s16> &dst)
 {
 	if(loadFromFolders()){
 		errorstream<<"Map::listAllLoadableBlocks(): Result will be missing "
 				<<"all blocks that are stored in flat files"<<std::endl;
 	}
-
-	{
-		verifyDatabase();
-
-		while(sqlite3_step(m_database_list) == SQLITE_ROW)
-		{
-			sqlite3_int64 block_i = sqlite3_column_int64(m_database_list, 0);
-			v3s16 p = getIntegerAsBlock(block_i);
-			//dstream<<"block_i="<<block_i<<" p="<<PP(p)<<std::endl;
-			dst.push_back(p);
-		}
-	}
+	dbase->listAllLoadableBlocks(dst);
 }
 
 void ServerMap::listAllLoadedBlocks(std::list<v3s16> &dst)
@@ -3457,20 +3042,21 @@ void ServerMap::saveMapMeta()
 	createDirs(m_savedir);
 
 	std::string fullpath = m_savedir + DIR_DELIM + "map_meta.txt";
-	std::ofstream os(fullpath.c_str(), std::ios_base::binary);
-	if(os.good() == false)
-	{
-		infostream<<"ERROR: ServerMap::saveMapMeta(): "
-				<<"could not open"<<fullpath<<std::endl;
-		throw FileNotGoodException("Cannot open chunk metadata");
-	}
+	std::ostringstream ss(std::ios_base::binary);
 
 	Settings params;
 
-	m_emerge->setParamsToSettings(&params);
-	params.writeLines(os);
+	m_emerge->saveParamsToSettings(&params);
+	params.writeLines(ss);
 
-	os<<"[end_of_params]\n";
+	ss<<"[end_of_params]\n";
+
+	if(!fs::safeWriteToFile(fullpath, ss.str()))
+	{
+		infostream<<"ERROR: ServerMap::saveMapMeta(): "
+				<<"could not write "<<fullpath<<std::endl;
+		throw FileNotGoodException("Cannot save chunk metadata");
+	}
 
 	m_map_metadata_changed = false;
 }
@@ -3505,47 +3091,30 @@ void ServerMap::loadMapMeta()
 			break;
 		params.parseConfigLine(line);
 	}
-	
-	MapgenParams *mgparams;
-	try {
-		mgparams = m_emerge->getParamsFromSettings(&params);
-	} catch (SettingNotFoundException &e) {
-		infostream << "Couldn't get a setting from map_meta.txt: "
-				   << e.what() << std::endl;
-		mgparams = NULL;
-	}
-	
-	if (mgparams) {
-		if (m_mgparams)
-			delete m_mgparams;
-		m_mgparams = mgparams;
-		m_seed = mgparams->seed;
-	} else {
-		if (params.exists("seed")) {
-			m_seed = params.getU64("seed");
-			m_mgparams->seed = m_seed;
-		}
-	}
 
-	verbosestream<<"ServerMap::loadMapMeta(): "<<"seed="<<m_seed<<std::endl;
+	m_emerge->loadParamsFromSettings(&params);
+
+	verbosestream<<"ServerMap::loadMapMeta(): seed="
+		<< m_emerge->params.seed<<std::endl;
 }
 
 void ServerMap::saveSectorMeta(ServerMapSector *sector)
 {
 	DSTACK(__FUNCTION_NAME);
 	// Format used for writing
-	u8 version = SER_FMT_VER_HIGHEST;
+	u8 version = SER_FMT_VER_HIGHEST_WRITE;
 	// Get destination
 	v2s16 pos = sector->getPos();
 	std::string dir = getSectorDir(pos);
 	createDirs(dir);
 
 	std::string fullpath = dir + DIR_DELIM + "meta";
-	std::ofstream o(fullpath.c_str(), std::ios_base::binary);
-	if(o.good() == false)
-		throw FileNotGoodException("Cannot open sector metafile");
+	std::ostringstream ss(std::ios_base::binary);
+
+	sector->serialize(ss, version);
 
-	sector->serialize(o, version);
+	if(!fs::safeWriteToFile(fullpath, ss.str()))
+		throw FileNotGoodException("Cannot write sector metafile");
 
 	sector->differs_from_disk = false;
 }
@@ -3706,97 +3275,59 @@ bool ServerMap::loadSectorFull(v2s16 p2d)
 }
 #endif
 
-void ServerMap::beginSave() {
-	verifyDatabase();
-	if(sqlite3_exec(m_database, "BEGIN;", NULL, NULL, NULL) != SQLITE_OK)
-		infostream<<"WARNING: beginSave() failed, saving might be slow.";
+void ServerMap::beginSave()
+{
+	dbase->beginSave();
 }
 
-void ServerMap::endSave() {
-	verifyDatabase();
-	if(sqlite3_exec(m_database, "COMMIT;", NULL, NULL, NULL) != SQLITE_OK)
-		infostream<<"WARNING: endSave() failed, map might not have saved.";
+void ServerMap::endSave()
+{
+	dbase->endSave();
 }
 
-void ServerMap::saveBlock(MapBlock *block)
+bool ServerMap::saveBlock(MapBlock *block)
 {
-	DSTACK(__FUNCTION_NAME);
-	/*
-		Dummy blocks are not written
-	*/
-	if(block->isDummy())
-	{
-		/*v3s16 p = block->getPos();
-		infostream<<"ServerMap::saveBlock(): WARNING: Not writing dummy block "
-				<<"("<<p.X<<","<<p.Y<<","<<p.Z<<")"<<std::endl;*/
-		return;
-	}
+	return saveBlock(block, dbase);
+}
 
-	// Format used for writing
-	u8 version = SER_FMT_VER_HIGHEST;
-	// Get destination
+bool ServerMap::saveBlock(MapBlock *block, Database *db)
+{
 	v3s16 p3d = block->getPos();
 
+	// Dummy blocks are not written
+	if (block->isDummy()) {
+		errorstream << "WARNING: saveBlock: Not writing dummy block "
+			<< PP(p3d) << std::endl;
+		return true;
+	}
 
-#if 0
-	v2s16 p2d(p3d.X, p3d.Z);
-	std::string sectordir = getSectorDir(p2d);
-
-	createDirs(sectordir);
+	// Format used for writing
+	u8 version = SER_FMT_VER_HIGHEST_WRITE;
 
-	std::string fullpath = sectordir+DIR_DELIM+getBlockFilename(p3d);
-	std::ofstream o(fullpath.c_str(), std::ios_base::binary);
-	if(o.good() == false)
-		throw FileNotGoodException("Cannot open block data");
-#endif
 	/*
 		[0] u8 serialization version
 		[1] data
 	*/
-
-	verifyDatabase();
-
 	std::ostringstream o(std::ios_base::binary);
-
-	o.write((char*)&version, 1);
-
-	// Write basic data
+	o.write((char*) &version, 1);
 	block->serialize(o, version, true);
 
-	// Write block to database
-
-	std::string tmp = o.str();
-	const char *bytes = tmp.c_str();
-
-	bool success = true;
-	if(sqlite3_bind_int64(m_database_write, 1, getBlockAsInteger(p3d)) != SQLITE_OK) {
-		infostream<<"WARNING: Block position failed to bind: "<<sqlite3_errmsg(m_database)<<std::endl;
-		success = false;
-	}
-	if(sqlite3_bind_blob(m_database_write, 2, (void *)bytes, o.tellp(), NULL) != SQLITE_OK) { // TODO this mught not be the right length
-		infostream<<"WARNING: Block data failed to bind: "<<sqlite3_errmsg(m_database)<<std::endl;
-		success = false;
-	}
-	int written = sqlite3_step(m_database_write);
-	if(written != SQLITE_DONE) {
-		errorstream<<"WARNING: Block failed to save ("<<p3d.X<<", "<<p3d.Y<<", "<<p3d.Z<<") "
-				<<sqlite3_errmsg(m_database)<<std::endl;
-		success = false;
-	}
-	// Make ready for later reuse
-	sqlite3_reset(m_database_write);
-
-	// We just wrote it to the disk so clear modified flag
-	if (success)
+	std::string data = o.str();
+	bool ret = db->saveBlock(p3d, data);
+	if(ret) {
+		// We just wrote it to the disk so clear modified flag
 		block->resetModified();
+	}
+	return ret;
 }
 
-void ServerMap::loadBlock(std::string sectordir, std::string blockfile, MapSector *sector, bool save_after_load)
+void ServerMap::loadBlock(std::string sectordir, std::string blockfile,
+		MapSector *sector, bool save_after_load)
 {
 	DSTACK(__FUNCTION_NAME);
 
 	std::string fullpath = sectordir+DIR_DELIM+blockfile;
-	try{
+	try {
 
 		std::ifstream is(fullpath.c_str(), std::ios_base::binary);
 		if(is.good() == false)
@@ -3841,7 +3372,7 @@ void ServerMap::loadBlock(std::string sectordir, std::string blockfile, MapSecto
 			Save blocks loaded in old format in new format
 		*/
 
-		if(version < SER_FMT_VER_HIGHEST || save_after_load)
+		if(version < SER_FMT_VER_HIGHEST_WRITE || save_after_load)
 		{
 			saveBlock(block);
 
@@ -3860,7 +3391,7 @@ void ServerMap::loadBlock(std::string sectordir, std::string blockfile, MapSecto
 				<<" (SerializationError). "
 				<<"what()="<<e.what()
 				<<std::endl;
-				//" Ignoring. A new one will be generated.
+				// Ignoring. A new one will be generated.
 		assert(0);
 
 		// TODO: Backup file; name is in fullpath.
@@ -3908,7 +3439,7 @@ void ServerMap::loadBlock(std::string *blob, v3s16 p3d, MapSector *sector, bool
 			Save blocks loaded in old format in new format
 		*/
 
-		//if(version < SER_FMT_VER_HIGHEST || save_after_load)
+		//if(version < SER_FMT_VER_HIGHEST_READ || save_after_load)
 		// Only save if asked to; no need to update version
 		if(save_after_load)
 			saveBlock(block);
@@ -3942,38 +3473,14 @@ MapBlock* ServerMap::loadBlock(v3s16 blockpos)
 
 	v2s16 p2d(blockpos.X, blockpos.Z);
 
-	if(!loadFromFolders()) {
-		verifyDatabase();
+	std::string ret;
 
-		if(sqlite3_bind_int64(m_database_read, 1, getBlockAsInteger(blockpos)) != SQLITE_OK)
-			infostream<<"WARNING: Could not bind block position for load: "
-				<<sqlite3_errmsg(m_database)<<std::endl;
-		if(sqlite3_step(m_database_read) == SQLITE_ROW) {
-			/*
-				Make sure sector is loaded
-			*/
-			MapSector *sector = createSector(p2d);
-
-			/*
-				Load block
-			*/
-			const char * data = (const char *)sqlite3_column_blob(m_database_read, 0);
-			size_t len = sqlite3_column_bytes(m_database_read, 0);
-
-			std::string datastr(data, len);
-
-			loadBlock(&datastr, blockpos, sector, false);
-
-			sqlite3_step(m_database_read);
-			// We should never get more than 1 row, so ok to reset
-			sqlite3_reset(m_database_read);
-
-			return getBlockNoCreateNoEx(blockpos);
-		}
-		sqlite3_reset(m_database_read);
-
-		// Not found in database, try the files
+	ret = dbase->loadBlock(blockpos);
+	if (ret != "") {
+		loadBlock(&ret, blockpos, createSector(p2d), false);
+		return getBlockNoCreateNoEx(blockpos);
 	}
+	// Not found in database, try the files
 
 	// The directory layout we're going to load from.
 	//  1 - original sectors/xxxxzzzz/
@@ -4036,167 +3543,11 @@ void ServerMap::PrintInfo(std::ostream &out)
 	out<<"ServerMap: ";
 }
 
-/*
-	MapVoxelManipulator
-*/
-
-MapVoxelManipulator::MapVoxelManipulator(Map *map)
-{
-	m_map = map;
-}
-
-MapVoxelManipulator::~MapVoxelManipulator()
-{
-	/*infostream<<"MapVoxelManipulator: blocks: "<<m_loaded_blocks.size()
-			<<std::endl;*/
-}
-
-void MapVoxelManipulator::emerge(VoxelArea a, s32 caller_id)
-{
-	TimeTaker timer1("emerge", &emerge_time);
-
-	// Units of these are MapBlocks
-	v3s16 p_min = getNodeBlockPos(a.MinEdge);
-	v3s16 p_max = getNodeBlockPos(a.MaxEdge);
-
-	VoxelArea block_area_nodes
-			(p_min*MAP_BLOCKSIZE, (p_max+1)*MAP_BLOCKSIZE-v3s16(1,1,1));
-
-	addArea(block_area_nodes);
-
-	for(s32 z=p_min.Z; z<=p_max.Z; z++)
-	for(s32 y=p_min.Y; y<=p_max.Y; y++)
-	for(s32 x=p_min.X; x<=p_max.X; x++)
-	{
-		u8 flags = 0;
-		MapBlock *block;
-		v3s16 p(x,y,z);
-		std::map<v3s16, u8>::iterator n;
-		n = m_loaded_blocks.find(p);
-		if(n != m_loaded_blocks.end())
-			continue;
-
-		bool block_data_inexistent = false;
-		try
-		{
-			TimeTaker timer1("emerge load", &emerge_load_time);
-
-			/*infostream<<"Loading block (caller_id="<<caller_id<<")"
-					<<" ("<<p.X<<","<<p.Y<<","<<p.Z<<")"
-					<<" wanted area: ";
-			a.print(infostream);
-			infostream<<std::endl;*/
-
-			block = m_map->getBlockNoCreate(p);
-			if(block->isDummy())
-				block_data_inexistent = true;
-			else
-				block->copyTo(*this);
-		}
-		catch(InvalidPositionException &e)
-		{
-			block_data_inexistent = true;
-		}
-
-		if(block_data_inexistent)
-		{
-			flags |= VMANIP_BLOCK_DATA_INEXIST;
-
-			VoxelArea a(p*MAP_BLOCKSIZE, (p+1)*MAP_BLOCKSIZE-v3s16(1,1,1));
-			// Fill with VOXELFLAG_INEXISTENT
-			for(s32 z=a.MinEdge.Z; z<=a.MaxEdge.Z; z++)
-			for(s32 y=a.MinEdge.Y; y<=a.MaxEdge.Y; y++)
-			{
-				s32 i = m_area.index(a.MinEdge.X,y,z);
-				memset(&m_flags[i], VOXELFLAG_INEXISTENT, MAP_BLOCKSIZE);
-			}
-		}
-		/*else if (block->getNode(0, 0, 0).getContent() == CONTENT_IGNORE)
-		{
-			// Mark that block was loaded as blank
-			flags |= VMANIP_BLOCK_CONTAINS_CIGNORE;
-		}*/
-
-		m_loaded_blocks[p] = flags;
-	}
-
-	//infostream<<"emerge done"<<std::endl;
-}
-
-/*
-	SUGG: Add an option to only update eg. water and air nodes.
-	      This will make it interfere less with important stuff if
-		  run on background.
-*/
-void MapVoxelManipulator::blitBack
-		(std::map<v3s16, MapBlock*> & modified_blocks)
-{
-	if(m_area.getExtent() == v3s16(0,0,0))
-		return;
-
-	//TimeTaker timer1("blitBack");
-
-	/*infostream<<"blitBack(): m_loaded_blocks.size()="
-			<<m_loaded_blocks.size()<<std::endl;*/
-
-	/*
-		Initialize block cache
-	*/
-	v3s16 blockpos_last;
-	MapBlock *block = NULL;
-	bool block_checked_in_modified = false;
-
-	for(s32 z=m_area.MinEdge.Z; z<=m_area.MaxEdge.Z; z++)
-	for(s32 y=m_area.MinEdge.Y; y<=m_area.MaxEdge.Y; y++)
-	for(s32 x=m_area.MinEdge.X; x<=m_area.MaxEdge.X; x++)
-	{
-		v3s16 p(x,y,z);
-
-		u8 f = m_flags[m_area.index(p)];
-		if(f & (VOXELFLAG_NOT_LOADED|VOXELFLAG_INEXISTENT))
-			continue;
-
-		MapNode &n = m_data[m_area.index(p)];
-
-		v3s16 blockpos = getNodeBlockPos(p);
-
-		try
-		{
-			// Get block
-			if(block == NULL || blockpos != blockpos_last){
-				block = m_map->getBlockNoCreate(blockpos);
-				blockpos_last = blockpos;
-				block_checked_in_modified = false;
-			}
-
-			// Calculate relative position in block
-			v3s16 relpos = p - blockpos * MAP_BLOCKSIZE;
-
-			// Don't continue if nothing has changed here
-			if(block->getNode(relpos) == n)
-				continue;
-
-			//m_map->setNode(m_area.MinEdge + p, n);
-			block->setNode(relpos, n);
-
-			/*
-				Make sure block is in modified_blocks
-			*/
-			if(block_checked_in_modified == false)
-			{
-				modified_blocks[blockpos] = block;
-				block_checked_in_modified = true;
-			}
-		}
-		catch(InvalidPositionException &e)
-		{
-		}
-	}
-}
-
 ManualMapVoxelManipulator::ManualMapVoxelManipulator(Map *map):
-		MapVoxelManipulator(map),
-		m_create_area(false)
+		VoxelManipulator(),
+		m_is_dirty(false),
+		m_create_area(false),
+		m_map(map)
 {
 }
 
@@ -4204,12 +3555,6 @@ ManualMapVoxelManipulator::~ManualMapVoxelManipulator()
 {
 }
 
-void ManualMapVoxelManipulator::emerge(VoxelArea a, s32 caller_id)
-{
-	// Just create the area so that it can be pointed to
-	VoxelManipulator::emerge(a, caller_id);
-}
-
 void ManualMapVoxelManipulator::initialEmerge(v3s16 blockpos_min,
 						v3s16 blockpos_max, bool load_if_inexistent)
 {
@@ -4263,7 +3608,7 @@ void ManualMapVoxelManipulator::initialEmerge(v3s16 blockpos_min,
 
 		if(block_data_inexistent)
 		{
-			
+
 			if (load_if_inexistent) {
 				ServerMap *svrmap = (ServerMap *)m_map;
 				block = svrmap->emergeBlock(p, false);
@@ -4273,17 +3618,17 @@ void ManualMapVoxelManipulator::initialEmerge(v3s16 blockpos_min,
 					block->copyTo(*this);
 			} else {
 				flags |= VMANIP_BLOCK_DATA_INEXIST;
-				
+
 				/*
 					Mark area inexistent
 				*/
 				VoxelArea a(p*MAP_BLOCKSIZE, (p+1)*MAP_BLOCKSIZE-v3s16(1,1,1));
-				// Fill with VOXELFLAG_INEXISTENT
+				// Fill with VOXELFLAG_NO_DATA
 				for(s32 z=a.MinEdge.Z; z<=a.MaxEdge.Z; z++)
 				for(s32 y=a.MinEdge.Y; y<=a.MaxEdge.Y; y++)
 				{
 					s32 i = m_area.index(a.MinEdge.X,y,z);
-					memset(&m_flags[i], VOXELFLAG_INEXISTENT, MAP_BLOCKSIZE);
+					memset(&m_flags[i], VOXELFLAG_NO_DATA, MAP_BLOCKSIZE);
 				}
 			}
 		}
@@ -4295,10 +3640,13 @@ void ManualMapVoxelManipulator::initialEmerge(v3s16 blockpos_min,
 
 		m_loaded_blocks[p] = flags;
 	}
+
+	m_is_dirty = false;
 }
 
 void ManualMapVoxelManipulator::blitBackAll(
-		std::map<v3s16, MapBlock*> * modified_blocks)
+		std::map<v3s16, MapBlock*> *modified_blocks,
+		bool overwrite_generated)
 {
 	if(m_area.getExtent() == v3s16(0,0,0))
 		return;
@@ -4313,10 +3661,9 @@ void ManualMapVoxelManipulator::blitBackAll(
 		v3s16 p = i->first;
 		MapBlock *block = m_map->getBlockNoCreateNoEx(p);
 		bool existed = !(i->second & VMANIP_BLOCK_DATA_INEXIST);
-		if(existed == false)
-		{
+		if ((existed == false) || (block == NULL) ||
+			(overwrite_generated == false && block->isGenerated() == true))
 			continue;
-		}
 
 		block->copyFrom(*this);