Detect air-only blocks instead of day/night differences (#14264)

* Detect air-only blocks instead day/night differences

* Write !is_air into the former day-night-diff bit on disk, so that old server can still read maps written by new servers

* Only set is_air bit when reading from disk
This commit is contained in:
lhofhansl 2024-02-22 21:47:42 -08:00 committed by GitHub
parent 0d30a3071a
commit 0d4b489545
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GPG Key ID: B5690EEEBB952194
5 changed files with 52 additions and 75 deletions

@ -2091,8 +2091,7 @@ liquid_update (Liquid update tick) float 1.0 0.001
# At this distance the server will aggressively optimize which blocks are sent to
# clients.
# Small values potentially improve performance a lot, at the expense of visible
# rendering glitches (some blocks will not be rendered under water and in caves,
# as well as sometimes on land).
# rendering glitches (some blocks might not be rendered correctly in caves).
# Setting this to a value greater than max_block_send_distance disables this
# optimization.
# Stated in MapBlocks (16 nodes).

@ -228,12 +228,12 @@ void Map::addNodeAndUpdate(v3s16 p, MapNode n,
std::vector<std::pair<v3s16, MapNode> > oldnodes;
oldnodes.emplace_back(p, oldnode);
voxalgo::update_lighting_nodes(this, oldnodes, modified_blocks);
for (auto &modified_block : modified_blocks) {
modified_block.second->expireDayNightDiff();
}
}
if (n.getContent() != oldnode.getContent() &&
(oldnode.getContent() == CONTENT_AIR || n.getContent() == CONTENT_AIR))
block->expireIsAirCache();
// Report for rollback
if(m_gamedef->rollback())
{
@ -1462,14 +1462,14 @@ void ServerMap::finishBlockMake(BlockMakeData *data,
if (!block)
continue;
/*
Update day/night difference cache of the MapBlocks
Update is air cache of the MapBlocks
*/
block->expireDayNightDiff();
block->expireIsAirCache();
/*
Set block as modified
*/
block->raiseModified(MOD_STATE_WRITE_NEEDED,
MOD_REASON_EXPIRE_DAYNIGHTDIFF);
MOD_REASON_EXPIRE_IS_AIR);
}
/*
@ -2064,6 +2064,7 @@ void MMVManip::blitBackAll(std::map<v3s16, MapBlock*> *modified_blocks,
block->copyFrom(*this);
block->raiseModified(MOD_STATE_WRITE_NEEDED, MOD_REASON_VMANIP);
block->expireIsAirCache();
if(modified_blocks)
(*modified_blocks)[p] = block;

@ -186,57 +186,27 @@ void MapBlock::copyFrom(VoxelManipulator &dst)
getPosRelative(), data_size);
}
void MapBlock::actuallyUpdateDayNightDiff()
void MapBlock::actuallyUpdateIsAir()
{
const NodeDefManager *nodemgr = m_gamedef->ndef();
// Running this function un-expires m_is_air
m_is_air_expired = false;
// Running this function un-expires m_day_night_differs
m_day_night_differs_expired = false;
bool differs = false;
/*
Check if any lighting value differs
*/
MapNode previous_n(CONTENT_IGNORE);
bool only_air = true;
for (u32 i = 0; i < nodecount; i++) {
MapNode n = data[i];
// If node is identical to previous node, don't verify if it differs
if (n == previous_n)
continue;
differs = !n.isLightDayNightEq(nodemgr->getLightingFlags(n));
if (differs)
MapNode &n = data[i];
if (n.getContent() != CONTENT_AIR) {
only_air = false;
break;
previous_n = n;
}
/*
If some lighting values differ, check if the whole thing is
just air. If it is just air, differs = false
*/
if (differs) {
bool only_air = true;
for (u32 i = 0; i < nodecount; i++) {
MapNode &n = data[i];
if (n.getContent() != CONTENT_AIR) {
only_air = false;
break;
}
}
if (only_air)
differs = false;
}
// Set member variable
m_day_night_differs = differs;
m_is_air = only_air;
}
void MapBlock::expireDayNightDiff()
void MapBlock::expireIsAirCache()
{
m_day_night_differs_expired = true;
m_is_air_expired = true;
}
/*
@ -369,7 +339,12 @@ void MapBlock::serialize(std::ostream &os_compressed, u8 version, bool disk, int
u8 flags = 0;
if(is_underground)
flags |= 0x01;
if(getDayNightDiff())
// This flag used to be day-night-differs, and it is no longer used.
// We write it anyway so that old servers can still use this.
// Above ground isAir implies !day-night-differs, !isAir is good enough for old servers
// to check whether above ground blocks should be sent.
// See RemoteClient::getNextBlocks(...)
if(!isAir())
flags |= 0x02;
if (!m_generated)
flags |= 0x08;
@ -473,7 +448,7 @@ void MapBlock::deSerialize(std::istream &in_compressed, u8 version, bool disk)
TRACESTREAM(<<"MapBlock::deSerialize "<<getPos()<<std::endl);
m_day_night_differs_expired = false;
m_is_air_expired = true;
if(version <= 21)
{
@ -489,7 +464,9 @@ void MapBlock::deSerialize(std::istream &in_compressed, u8 version, bool disk)
u8 flags = readU8(is);
is_underground = (flags & 0x01) != 0;
m_day_night_differs = (flags & 0x02) != 0;
// IMPORTANT: when the version is bumped to 30 we can read m_is_air from here
// m_is_air = (flags & 0x02) == 0;
if (version < 27)
m_lighting_complete = 0xFFFF;
else
@ -599,6 +576,10 @@ void MapBlock::deSerialize(std::istream &in_compressed, u8 version, bool disk)
<<": Node timers (ver>=25)"<<std::endl);
m_node_timers.deSerialize(is, version);
}
u16 dummy;
m_is_air = nimap.size() == 1 && nimap.getId("air", dummy);
m_is_air_expired = false;
}
TRACESTREAM(<<"MapBlock::deSerialize "<<getPos()
@ -647,7 +628,7 @@ void MapBlock::deSerialize_pre22(std::istream &is, u8 version, bool disk)
{
// Initialize default flags
is_underground = false;
m_day_night_differs = false;
m_is_air = false;
m_lighting_complete = 0xFFFF;
m_generated = true;
@ -713,7 +694,6 @@ void MapBlock::deSerialize_pre22(std::istream &is, u8 version, bool disk)
u8 flags;
is.read((char*)&flags, 1);
is_underground = (flags & 0x01) != 0;
m_day_night_differs = (flags & 0x02) != 0;
if (version >= 18)
m_generated = (flags & 0x08) == 0;
@ -798,9 +778,13 @@ void MapBlock::deSerialize_pre22(std::istream &is, u8 version, bool disk)
// If supported, read node definition id mapping
if (version >= 21) {
nimap.deSerialize(is);
u16 dummy;
m_is_air = nimap.size() == 1 && nimap.getId("air", dummy);
// Else set the legacy mapping
} else {
content_mapnode_get_name_id_mapping(&nimap);
m_is_air = false;
m_is_air_expired = true;
}
correctBlockNodeIds(&nimap, data, m_gamedef);
}

@ -60,7 +60,7 @@ enum ModReason : u32 {
MOD_REASON_STATIC_DATA_ADDED = 1 << 13,
MOD_REASON_STATIC_DATA_REMOVED = 1 << 14,
MOD_REASON_STATIC_DATA_CHANGED = 1 << 15,
MOD_REASON_EXPIRE_DAYNIGHTDIFF = 1 << 16,
MOD_REASON_EXPIRE_IS_AIR = 1 << 16,
MOD_REASON_VMANIP = 1 << 17,
MOD_REASON_UNKNOWN = 1 << 18,
};
@ -310,20 +310,19 @@ public:
// Copies data from VoxelManipulator getPosRelative()
void copyFrom(VoxelManipulator &dst);
// Update day-night lighting difference flag.
// Sets m_day_night_differs to appropriate value.
// These methods don't care about neighboring blocks.
void actuallyUpdateDayNightDiff();
// Update is air flag.
// Sets m_is_air to appropriate value.
void actuallyUpdateIsAir();
// Call this to schedule what the previous function does to be done
// when the value is actually needed.
void expireDayNightDiff();
void expireIsAirCache();
inline bool getDayNightDiff()
inline bool isAir()
{
if (m_day_night_differs_expired)
actuallyUpdateDayNightDiff();
return m_day_night_differs;
if (m_is_air_expired)
actuallyUpdateIsAir();
return m_is_air;
}
bool onObjectsActivation();
@ -517,8 +516,8 @@ public:
private:
// Whether day and night lighting differs
bool m_day_night_differs = false;
bool m_day_night_differs_expired = true;
bool m_is_air = false;
bool m_is_air_expired = true;
/*
- On the server, this is used for telling whether the

@ -354,18 +354,12 @@ void RemoteClient::GetNextBlocks (
continue;
/*
If block is not close, don't send it unless it is near
ground level.
Block is near ground level if night-time mesh
differs from day-time mesh.
If block is not close, don't send it if it
consists of air only.
*/
if (d >= d_opt) {
if (!block->getIsUnderground() && !block->getDayNightDiff())
if (d >= d_opt && block->isAir())
continue;
}
}
/*
Check occlusion cache first.
*/