Light calculation: New bulk node lighting code

This commit introduces a new bulk node lighting algorithm to minimize
lighting bugs during l-system tree generation, schematic placement and
non-mapgen-object lua voxelmanip light calculation.

If the block above the changed area is not loaded, it gets loaded to avoid
lighting bugs.
Light is updated as soon as write_to_map is called on a voxel manipulator,
therefore update_map does nothing.

1 files changed, 0 insertions, 565 deletions

diff --git a/src/map.cpp b/src/map.cpp
index a415bda96..a1502befa 100644
--- a/src/map.cpp
+++ b/src/map.cpp
@@ -235,571 +235,6 @@ void Map::setNode(v3s16 p, MapNode & n)
 	block->setNodeNoCheck(relpos, n);
 }
 
-/*
-	Goes recursively through the neighbours of the node.
-
-	Alters only transparent nodes.
-
-	If the lighting of the neighbour is lower than the lighting of
-	the node was (before changing it to 0 at the step before), the
-	lighting of the neighbour is set to 0 and then the same stuff
-	repeats for the neighbour.
-
-	The ending nodes of the routine are stored in light_sources.
-	This is useful when a light is removed. In such case, this
-	routine can be called for the light node and then again for
-	light_sources to re-light the area without the removed light.
-
-	values of from_nodes are lighting values.
-*/
-void Map::unspreadLight(enum LightBank bank,
-		std::map<v3s16, u8> & from_nodes,
-		std::set<v3s16> & light_sources,
-		std::map<v3s16, MapBlock*>  & modified_blocks)
-{
-	v3s16 dirs[6] = {
-		v3s16(0,0,1), // back
-		v3s16(0,1,0), // top
-		v3s16(1,0,0), // right
-		v3s16(0,0,-1), // front
-		v3s16(0,-1,0), // bottom
-		v3s16(-1,0,0), // left
-	};
-
-	if(from_nodes.empty())
-		return;
-
-	u32 blockchangecount = 0;
-
-	std::map<v3s16, u8> unlighted_nodes;
-
-	/*
-		Initialize block cache
-	*/
-	v3s16 blockpos_last;
-	MapBlock *block = NULL;
-	// Cache this a bit, too
-	bool block_checked_in_modified = false;
-
-	for(std::map<v3s16, u8>::iterator j = from_nodes.begin();
-		j != from_nodes.end(); ++j)
-	{
-		v3s16 pos = j->first;
-		v3s16 blockpos = getNodeBlockPos(pos);
-
-		// Only fetch a new block if the block position has changed
-		try{
-			if(block == NULL || blockpos != blockpos_last){
-				block = getBlockNoCreate(blockpos);
-				blockpos_last = blockpos;
-
-				block_checked_in_modified = false;
-				blockchangecount++;
-			}
-		}
-		catch(InvalidPositionException &e)
-		{
-			continue;
-		}
-
-		if(block->isDummy())
-			continue;
-
-		// Calculate relative position in block
-		//v3s16 relpos = pos - blockpos_last * MAP_BLOCKSIZE;
-
-		// Get node straight from the block
-		//MapNode n = block->getNode(relpos);
-
-		u8 oldlight = j->second;
-
-		// Loop through 6 neighbors
-		for(u16 i=0; i<6; i++)
-		{
-			// Get the position of the neighbor node
-			v3s16 n2pos = pos + dirs[i];
-
-			// Get the block where the node is located
-			v3s16 blockpos, relpos;
-			getNodeBlockPosWithOffset(n2pos, blockpos, relpos);
-
-			// Only fetch a new block if the block position has changed
-			try {
-				if(block == NULL || blockpos != blockpos_last){
-					block = getBlockNoCreate(blockpos);
-					blockpos_last = blockpos;
-
-					block_checked_in_modified = false;
-					blockchangecount++;
-				}
-			}
-			catch(InvalidPositionException &e) {
-				continue;
-			}
-
-			// Get node straight from the block
-			bool is_valid_position;
-			MapNode n2 = block->getNode(relpos, &is_valid_position);
-			if (!is_valid_position)
-				continue;
-
-			bool changed = false;
-
-			//TODO: Optimize output by optimizing light_sources?
-
-			/*
-				If the neighbor is dimmer than what was specified
-				as oldlight (the light of the previous node)
-			*/
-			if(n2.getLight(bank, m_nodedef) < oldlight)
-			{
-				/*
-					And the neighbor is transparent and it has some light
-				*/
-				if(m_nodedef->get(n2).light_propagates
-						&& n2.getLight(bank, m_nodedef) != 0)
-				{
-					/*
-						Set light to 0 and add to queue
-					*/
-
-					u8 current_light = n2.getLight(bank, m_nodedef);
-					n2.setLight(bank, 0, m_nodedef);
-					block->setNode(relpos, n2);
-
-					unlighted_nodes[n2pos] = current_light;
-					changed = true;
-
-					/*
-						Remove from light_sources if it is there
-						NOTE: This doesn't happen nearly at all
-					*/
-					/*if(light_sources.find(n2pos))
-					{
-						infostream<<"Removed from light_sources"<<std::endl;
-						light_sources.remove(n2pos);
-					}*/
-				}
-
-				/*// DEBUG
-				if(light_sources.find(n2pos) != NULL)
-					light_sources.remove(n2pos);*/
-			}
-			else{
-				light_sources.insert(n2pos);
-			}
-
-			// Add to modified_blocks
-			if(changed == true && block_checked_in_modified == false)
-			{
-				// If the block is not found in modified_blocks, add.
-				if(modified_blocks.find(blockpos) == modified_blocks.end())
-				{
-					modified_blocks[blockpos] = block;
-				}
-				block_checked_in_modified = true;
-			}
-		}
-	}
-
-	/*infostream<<"unspreadLight(): Changed block "
-	<<blockchangecount<<" times"
-	<<" for "<<from_nodes.size()<<" nodes"
-	<<std::endl;*/
-
-	if(!unlighted_nodes.empty())
-		unspreadLight(bank, unlighted_nodes, light_sources, modified_blocks);
-}
-
-/*
-	Lights neighbors of from_nodes, collects all them and then
-	goes on recursively.
-*/
-void Map::spreadLight(enum LightBank bank,
-		std::set<v3s16> & from_nodes,
-		std::map<v3s16, MapBlock*> & modified_blocks)
-{
-	const v3s16 dirs[6] = {
-		v3s16(0,0,1), // back
-		v3s16(0,1,0), // top
-		v3s16(1,0,0), // right
-		v3s16(0,0,-1), // front
-		v3s16(0,-1,0), // bottom
-		v3s16(-1,0,0), // left
-	};
-
-	if(from_nodes.empty())
-		return;
-
-	u32 blockchangecount = 0;
-
-	std::set<v3s16> lighted_nodes;
-
-	/*
-		Initialize block cache
-	*/
-	v3s16 blockpos_last;
-	MapBlock *block = NULL;
-		// Cache this a bit, too
-	bool block_checked_in_modified = false;
-
-	for(std::set<v3s16>::iterator j = from_nodes.begin();
-		j != from_nodes.end(); ++j)
-	{
-		v3s16 pos = *j;
-		v3s16 blockpos, relpos;
-
-		getNodeBlockPosWithOffset(pos, blockpos, relpos);
-
-		// Only fetch a new block if the block position has changed
-		try {
-			if(block == NULL || blockpos != blockpos_last){
-				block = getBlockNoCreate(blockpos);
-				blockpos_last = blockpos;
-
-				block_checked_in_modified = false;
-				blockchangecount++;
-			}
-		}
-		catch(InvalidPositionException &e) {
-			continue;
-		}
-
-		if(block->isDummy())
-			continue;
-
-		// Get node straight from the block
-		bool is_valid_position;
-		MapNode n = block->getNode(relpos, &is_valid_position);
-
-		u8 oldlight = is_valid_position ? n.getLight(bank, m_nodedef) : 0;
-		u8 newlight = diminish_light(oldlight);
-
-		// Loop through 6 neighbors
-		for(u16 i=0; i<6; i++){
-			// Get the position of the neighbor node
-			v3s16 n2pos = pos + dirs[i];
-
-			// Get the block where the node is located
-			v3s16 blockpos, relpos;
-			getNodeBlockPosWithOffset(n2pos, blockpos, relpos);
-
-			// Only fetch a new block if the block position has changed
-			try {
-				if(block == NULL || blockpos != blockpos_last){
-					block = getBlockNoCreate(blockpos);
-					blockpos_last = blockpos;
-
-					block_checked_in_modified = false;
-					blockchangecount++;
-				}
-			}
-			catch(InvalidPositionException &e) {
-				continue;
-			}
-
-			// Get node straight from the block
-			MapNode n2 = block->getNode(relpos, &is_valid_position);
-			if (!is_valid_position)
-				continue;
-
-			bool changed = false;
-			/*
-				If the neighbor is brighter than the current node,
-				add to list (it will light up this node on its turn)
-			*/
-			if(n2.getLight(bank, m_nodedef) > undiminish_light(oldlight))
-			{
-				lighted_nodes.insert(n2pos);
-				changed = true;
-			}
-			/*
-				If the neighbor is dimmer than how much light this node
-				would spread on it, add to list
-			*/
-			if(n2.getLight(bank, m_nodedef) < newlight)
-			{
-				if(m_nodedef->get(n2).light_propagates)
-				{
-					n2.setLight(bank, newlight, m_nodedef);
-					block->setNode(relpos, n2);
-					lighted_nodes.insert(n2pos);
-					changed = true;
-				}
-			}
-
-			// Add to modified_blocks
-			if(changed == true && block_checked_in_modified == false)
-			{
-				// If the block is not found in modified_blocks, add.
-				if(modified_blocks.find(blockpos) == modified_blocks.end())
-				{
-					modified_blocks[blockpos] = block;
-				}
-				block_checked_in_modified = true;
-			}
-		}
-	}
-
-	/*infostream<<"spreadLight(): Changed block "
-			<<blockchangecount<<" times"
-			<<" for "<<from_nodes.size()<<" nodes"
-			<<std::endl;*/
-
-	if(!lighted_nodes.empty())
-		spreadLight(bank, lighted_nodes, modified_blocks);
-}
-
-void Map::updateLighting(enum LightBank bank,
-		std::map<v3s16, MapBlock*> & a_blocks,
-		std::map<v3s16, MapBlock*> & modified_blocks)
-{
-	/*m_dout<<"Map::updateLighting(): "
-			<<a_blocks.size()<<" blocks."<<std::endl;*/
-
-	//TimeTaker timer("updateLighting");
-
-	// For debugging
-	//bool debug=true;
-	//u32 count_was = modified_blocks.size();
-
-	//std::map<v3s16, MapBlock*> blocks_to_update;
-
-	std::set<v3s16> light_sources;
-
-	std::map<v3s16, u8> unlight_from;
-
-	int num_bottom_invalid = 0;
-
-	{
-	//TimeTaker t("first stuff");
-
-	for(std::map<v3s16, MapBlock*>::iterator i = a_blocks.begin();
-		i != a_blocks.end(); ++i)
-	{
-		MapBlock *block = i->second;
-
-		for(;;)
-		{
-			// Don't bother with dummy blocks.
-			if(block->isDummy())
-				break;
-
-			v3s16 pos = block->getPos();
-			v3s16 posnodes = block->getPosRelative();
-			modified_blocks[pos] = block;
-			//blocks_to_update[pos] = block;
-
-			/*
-				Clear all light from block
-			*/
-			for(s16 z=0; z<MAP_BLOCKSIZE; z++)
-			for(s16 x=0; x<MAP_BLOCKSIZE; x++)
-			for(s16 y=0; y<MAP_BLOCKSIZE; y++)
-			{
-				v3s16 p(x,y,z);
-				bool is_valid_position;
-				MapNode n = block->getNode(p, &is_valid_position);
-				if (!is_valid_position) {
-					/* This would happen when dealing with a
-					   dummy block.
-					*/
-					infostream<<"updateLighting(): InvalidPositionException"
-							<<std::endl;
-					continue;
-				}
-				u8 oldlight = n.getLight(bank, m_nodedef);
-				n.setLight(bank, 0, m_nodedef);
-				block->setNode(p, n);
-
-				// If node sources light, add to list
-				u8 source = m_nodedef->get(n).light_source;
-				if(source != 0)
-					light_sources.insert(p + posnodes);
-
-				// Collect borders for unlighting
-				if((x==0 || x == MAP_BLOCKSIZE-1
-						|| y==0 || y == MAP_BLOCKSIZE-1
-						|| z==0 || z == MAP_BLOCKSIZE-1)
-						&& oldlight != 0)
-				{
-					v3s16 p_map = p + posnodes;
-					unlight_from[p_map] = oldlight;
-				}
-
-
-			}
-
-			if(bank == LIGHTBANK_DAY)
-			{
-				bool bottom_valid = block->propagateSunlight(light_sources);
-
-				if(!bottom_valid)
-					num_bottom_invalid++;
-
-				// If bottom is valid, we're done.
-				if(bottom_valid)
-					break;
-			}
-			else if(bank == LIGHTBANK_NIGHT)
-			{
-				// For night lighting, sunlight is not propagated
-				break;
-			}
-			else
-			{
-				assert("Invalid lighting bank" == NULL);
-			}
-
-			/*infostream<<"Bottom for sunlight-propagated block ("
-					<<pos.X<<","<<pos.Y<<","<<pos.Z<<") not valid"
-					<<std::endl;*/
-
-			// Bottom sunlight is not valid; get the block and loop to it
-
-			pos.Y--;
-			try{
-				block = getBlockNoCreate(pos);
-			}
-			catch(InvalidPositionException &e)
-			{
-				FATAL_ERROR("Invalid position");
-			}
-
-		}
-	}
-
-	}
-
-	/*
-		Enable this to disable proper lighting for speeding up map
-		generation for testing or whatever
-	*/
-#if 0
-	//if(g_settings->get(""))
-	{
-		core::map<v3s16, MapBlock*>::Iterator i;
-		i = blocks_to_update.getIterator();
-		for(; i.atEnd() == false; i++)
-		{
-			MapBlock *block = i.getNode()->getValue();
-			v3s16 p = block->getPos();
-			block->setLightingExpired(false);
-		}
-		return;
-	}
-#endif
-
-#if 1
-	{
-		//TimeTaker timer("unspreadLight");
-		unspreadLight(bank, unlight_from, light_sources, modified_blocks);
-	}
-
-	/*if(debug)
-	{
-		u32 diff = modified_blocks.size() - count_was;
-		count_was = modified_blocks.size();
-		infostream<<"unspreadLight modified "<<diff<<std::endl;
-	}*/
-
-	{
-		//TimeTaker timer("spreadLight");
-		spreadLight(bank, light_sources, modified_blocks);
-	}
-
-	/*if(debug)
-	{
-		u32 diff = modified_blocks.size() - count_was;
-		count_was = modified_blocks.size();
-		infostream<<"spreadLight modified "<<diff<<std::endl;
-	}*/
-#endif
-
-#if 0
-	{
-		//MapVoxelManipulator vmanip(this);
-
-		// Make a manual voxel manipulator and load all the blocks
-		// that touch the requested blocks
-		ManualMapVoxelManipulator vmanip(this);
-
-		{
-		//TimeTaker timer("initialEmerge");
-
-		core::map<v3s16, MapBlock*>::Iterator i;
-		i = blocks_to_update.getIterator();
-		for(; i.atEnd() == false; i++)
-		{
-			MapBlock *block = i.getNode()->getValue();
-			v3s16 p = block->getPos();
-
-			// Add all surrounding blocks
-			vmanip.initialEmerge(p - v3s16(1,1,1), p + v3s16(1,1,1));
-
-			/*
-				Add all surrounding blocks that have up-to-date lighting
-				NOTE: This doesn't quite do the job (not everything
-					  appropriate is lighted)
-			*/
-			/*for(s16 z=-1; z<=1; z++)
-			for(s16 y=-1; y<=1; y++)
-			for(s16 x=-1; x<=1; x++)
-			{
-				v3s16 p2 = p + v3s16(x,y,z);
-				MapBlock *block = getBlockNoCreateNoEx(p2);
-				if(block == NULL)
-					continue;
-				if(block->isDummy())
-					continue;
-				if(block->getLightingExpired())
-					continue;
-				vmanip.initialEmerge(p2, p2);
-			}*/
-
-			// Lighting of block will be updated completely
-			block->setLightingExpired(false);
-		}
-		}
-
-		{
-			//TimeTaker timer("unSpreadLight");
-			vmanip.unspreadLight(bank, unlight_from, light_sources, nodemgr);
-		}
-		{
-			//TimeTaker timer("spreadLight");
-			vmanip.spreadLight(bank, light_sources, nodemgr);
-		}
-		{
-			//TimeTaker timer("blitBack");
-			vmanip.blitBack(modified_blocks);
-		}
-		/*infostream<<"emerge_time="<<emerge_time<<std::endl;
-		emerge_time = 0;*/
-	}
-#endif
-
-	//m_dout<<"Done ("<<getTimestamp()<<")"<<std::endl;
-}
-
-void Map::updateLighting(std::map<v3s16, MapBlock*> & a_blocks,
-		std::map<v3s16, MapBlock*> & modified_blocks)
-{
-	updateLighting(LIGHTBANK_DAY, a_blocks, modified_blocks);
-	updateLighting(LIGHTBANK_NIGHT, a_blocks, modified_blocks);
-
-	/*
-		Update information about whether day and night light differ
-	*/
-	for(std::map<v3s16, MapBlock*>::iterator
-			i = modified_blocks.begin();
-			i != modified_blocks.end(); ++i)
-	{
-		MapBlock *block = i->second;
-		block->expireDayNightDiff();
-	}
-}
-
 void Map::addNodeAndUpdate(v3s16 p, MapNode n,
 		std::map<v3s16, MapBlock*> &modified_blocks,
 		bool remove_metadata)