Mgvalleys: Remove riverbed sand placement from base terrain generation
Riverbed material placement moved to MapgenBasic::generateBiomes()
Document fields and add note that the biome API is still unstable
- Adds only ~100 nodes per chunk to trans_liquid with similar processing time
- Adds liquid nodes themselves instead of potential solid nodes below them
- CONTENT_IGNORE nodes are interpreted as if they continue their neighborhood
- This allows liquid columns to span multiple chunks without being interrupted
- NOTE: Expects an one-node border in generation chunk without liquid changes
Previously, rivers were sometimes blocked by vertical walls
of mountain terrain due to river carving being disabled
when base terrain height was below water_level - 16
Remove now unused base terrain heightmap created in
generateTerrain()
Gives a convenient way to check a player's password.
This entirely bypasses the SRP protocol, so should be used
with great care.
This function is not intended to be used
in-game, but solely by external protocols, where no
authentication of the minetest engine is provided, and
also only for protocols, in which the user already gives the
server the plaintext password.
Examples for good use are the classical http form, or irc,
an example for a bad use is a password change dialog inside
formspec.
Users should be aware that they lose the advantages of the SRP
protocol if they enter their passwords for servers outside the
normal entry box, like in in-game formspec menus,
or through irc /msg s,
This patch also fixes an auth.h mistake which has mixed up the
order of params inside the decode_srp_verifier_and_salt function.
Zeno-: Added errorstream message for invalid format when I committed
Adds the particle option `collision_removal = bool`
Some particles are hard to use right now since they either go through
solid blocks (without collision detection), and with collision
detection enabled they (e.g. raindrops) would just stop dead on the
floor and sit there until they expire, or worse, scrape along a wall
or ceiling.
We can solve the problem by adding a boolean flag that tells the
particle to be removed if it ever collides with something. This will
make it easier to add rain that doesn't fall through your roof or stick
on the top of it. Or clouds and smoke that don't go through trees.
Particles that collide with this flag are marked expired
unconditionally, causing them to be treated like normal expired
particles and cleaned up normally.
Documentation is adjusted accordingly.
An added bonus of this patch is that particles can potentially collide
many times with nodes, and this reduces the amount of collisions to 1
(max), which may end up reducing particle load on the client.
This commit moves noise calculation to the functions where the noise is
actually required, increasing the separation of concerns and level of
interdependency for each mapgen method. Valleys Mapgen is left unmodified.
- Convert instances of numeric literal doubles to floats
- Move dswitchint to a local variable now that being a member is unnecessary
- Improve const correctness
- Indentation fixes
MSVC and GCC evaluate parameters in right-to-left order, whereas Clang
evaluates in left-to-right order, and of course, an optimization could
leave the order of evaluation completely indeterminate.
This commit fixes all instances of the error by explicitly assigning the
results of expressions that use PseudoRandom::next() or range() to their
respective vector components.
The right-to-left evaluation behavior is preserved since Clang is much less
commonly used to compile Minetest than GCC and MSVC combined, and would
therefore cause the least harm.
BiomeGen defines an interface that, given a set of BiomeParams, computes biomes
for a given area using the algorithm implemented by that specific BiomeGen.
This abstracts away the old system where each mapgen supplied the noises
required for biome generation.
We can remove the function in MtNativeActivity now
as it serves precisely that purpose: to tell irrlicht
that we handled the esc key.
TODO for later:
* Perhaps try to find a more performant container than KeyList
Fixes a bug where packet reordering made the server give the
client two peer ids instead of one. This in turn confused
reliable packet sending and made connecting to the server fail.
The client usually sends three packets at init: one "dummy"
packet consisting of two 0 bytes, and the init packet as well as
its legacy counterpart. The last one can be turned off since commit
af30183124d40a969040d7de4b3a487feec466e4, but this is of lower
relevance for the bug. The relevant part here is that network
packet reorder (which is a normal occurence) can make the packets
reach the server in different order.
If reorder puts the dummy packet further behind, the following
would happen before the patch:
1. The server will get one of the init packets on channel 1 and
assign the client a peer id, as the packet will have zero as
peer id.
2. The server sends a CONTROLTYPE_SET_PEER_ID packet to inform
the client of the peer id.
3. The next packet from the client will contain the peer id set by
the server.
4. The server sets the m_has_sent_with_id member for the client's
peer structure to true.
5. Now the dummy packet arrives. It has a peer id of zero, therefore
the server searches whether it already has a peer id for the
address the packet was sent from. The search fails because
m_has_sent_with_id was set to true and the server only searched
for peers with m_has_sent_with_id set to false.
6. In a working setup, the server would assign the dummy packet to
the correct peer id. However the server instead now assigns a
second peer id and peer structure to the peer, and assign the
packet to that new peer.
7. In order to inform the peer of its peer id, the server sends a
CONTROLTYPE_SET_PEER_ID command packet, reliably, to the peer.
This packet uses the new peer id.
8. The client sends an ack to that packet, not with the new peer id
but with the peer id sent in 2.
9. This packet reaches the server, but it drops the ACK as the peer
id does not map to any un-ACK-ed packets with that seqnum. The
same time, the server still waits for an ACK with the new peer
id, which of course won't come. This causes the server to
periodically re-try sending that packet, and the client ACKing it
each time.
Steps 7-9 cause annoyances and erroneous output, but don't cause
the connection failure itself.
The actual mistake that causes the connection failure happens in 6:
The server does not assign the dummy packet to the correct peer, but
to a newly created one.
Therefore, all further packets sent by the client on channel 0 are
now buffered by the server as it waits for the dummy packet to reach
the peer, which of course doesn't happen as the server assigned
that packet to the second peer it created for the client.
This makes the connection code indefinitely buffer the
TOSERVER_CLIENT_READY packet, not passing it to higher level code,
which stalls the continuation of the further init process
indefinitely and causes the actual bug.
Maybe this can be caused by reordered init packets as well, the only
studied case was where network has reliably reordered the dummy
packet to get sent after the init packets.
The patch fixes the bug by not ignoring peers where
m_has_sent_with_id has been set anymore. The other changes of the
patch are just cleanups of unused methods and fields and additional
explanatory comments.
One could think of alternate ways to fix the bug:
* The client could simply take the new peer id and continue
communicating with that. This is however worse than the fix as
it requires the peer id set command to be sent reliably (which
currently happens, but it cant be changed anymore). Also, such a
change would require both server and client to be patched in order
for the bug to be fixed, as right now the client ignores peer id
set commands after the peer id is different from
PEER_ID_INEXISTENT and the server requires modification too to
change the peer id internally.
And, most importantly, right now we guarantee higher level server
code that the peer id for a certain peer does not change. This
guarantee would have to be broken, and it would require much
larger changes to the server than this patch means.
* One could stop sending the dummy packet. One may be unsure whether
this is a good idea, as the meaning of the dummy packet is not
known (it might be there for something important), and as it is
possible that the init packets may cause this problem as well
(although it may be possible too that they can't cause this).
Thanks to @auouymous who had originally reported this bug and who
has helped patiently in finding its cause.
