The path finding code works fairly well except that it considers
anythin not CONTENT_AIR to be "above the surface". This results in
paths that are unwalkable for entities since e.g. plants are not
walkable. The path would force them to jump on top of grass plants,
etc..
The obvious solution is not to use CONTENT_AIR as a criteria, but
instead distinguish between walkable and non-walkable nodes. This
results in paths that properly walk through grass nodes.
This was extensively tested by a flock of electric sheep.
Note that for underwater purposes this changes the behaviour from
"the surface is walkable" to "ignore water entirely" making the
path go across the water bottom, and pathing fail likely from the
water surface. This is intentional.
Before, the GridNodes were stored in vector<vector<vector<T>>>,
and initialized in advance. Putting three vectors inside each other
puts lots of unneccessary stress onto the allocator, costs more memory,
and has worse cache locality than a flat vector<T>.
For larger search distances, an the array getting initialized means
essentially O(distance^3) complexity in both time and memory,
which makes the current path search a joke. In order to really
profit from the dijkstra/A* algorithms, other data structures
need to be used for larger distances.
For shorter distances, a map based GridNode storage may be slow as
it requires lots of levels of indirection, which is bad for things like
cache locality, and an array based storage may be faster.
This commit does:
1. remove the vector<vector<vector<T>>> based GridNodes storage that
is allocated and initialized in advance and for the whole
possible area.
2. Add a vector<T> based GridNodes storage that is allocated and
initialized in advance for the whole possible area.
3. Add a map<P,T> based GridNodes storage whose elements are
allocated and initialized, when the path search code
demands it.
4. Add code to decide between approach 2 and 3,
based on the length of the path.
5. Remove the unused "surfaces" member of the PathGridnode class.
Setting this isn't as easy anymore for the
map based GridNodes storage.
* Fix naming style for methods and classes:
Use camelCase for methods and PascalCase for classes as
code style demands it. And use sneak_case for methods that
are not member of a class.
* Replace "* " with " *" for Pointers
* Same for references
* Put function body opening braces on new line
* Other misc minor non functional style improvements
There is no need to put them into the header, they are solely used
inside the pathfinder.
Another advantage of this change is that only the pathfinder.cpp has
to be compiled if PATHFINDER_DEBUG gets defined or undefined, not
all files including the .h.
This commit moves the pathfinder classes to the cpp file without
modifications.
Also, the PATHFINDER_DEBUG macro gets moved to the cpp file and
the PATHFINDER_CALC_TIME macro gets moved to a plce where it
actually does work.
Previously, race conditions occurred inside logging, that caused
segfaults because a thread was trying to use an old pointer that
was freed when the string was reallocated. Using a fixed-length buffer
avoids this, at the cost of cutting too long messages over seveal lines.
The shadow bug at y = 63 was caused by dark air being placed as dust,
when the biome dust was unspecified it was falling back to 'air'
In dustTopNodes only dust == 'ignore' will disable dust placement
Previous mountain terrain generation was by necessity placing
stone in air, this was removing air from any overgenerated
structures such as tunnels, dungeons and large caves
Moving it into the base terrain generation loop ensures that
only 'ignore' is replaced
generateRidgeTerrain: only return if node_max.Y < water_level - 16
Previously, if water level was set a few nodes above a mapchunk
border the river channel was only partially excavated
Instead of doing nothing at node_max.Y + 1 use 1-down
overgeneration for tunnel generation and noisemaps
Move some old unused code in mgv7 to end of file
It was caused by player not moving because fall was prevented, but their
velocity still increasing, causing fatal fall damage when world was
finally loaded. This commit fixes it by setting player velocity to zero
when the world around them is not loaded.
Commit
c3b279750ece0b5144bf8e973d55108347462223 "Move object nametags to camera"
has added a regression to still display
a shadow if their alpha got set to 0.
* Fix leak like behaviour if you load multiple schematics in a loop.
* Cleanup check in for, fixing theoretical out of bounds read if
Schematic::deserializeFromMts reduced the number of elements
in m_nodenames. A != check may need an overflow of the counter
before it hits, if origsize is larger than m_nodenames.size().
* Fix function name passed to errorstream: it was wrong. Also use
__FUNCTION__ instead of manually using the method name at other
places in the function.
* Don't shadow the name member in the loop.
This fixes#3935, a regression from 0338c2e.
An 'optimization' was performed where an index for the VoxelManip being
operated on was mistakenly used for bounds checking within the incorrect
VoxelArea, namely, the area wherein light should be spread.
This allows the player to more easily target and punch connected
nodeboxes, especially if they have a fixed nodebox that is very
small, like technic cabling, or xpanes. Tried it on fences and
my xpane conversion, and happy with the result.
Changes:
* Fix indentation.
* Pass strings by const reference.
* Merge Strfnd and WStrfnd into one class instead of copying them.
* Remove trailing spaces.
* Fix variable names.
* Move to util.
* Other miscellaneous style fixes.
ABM's are hardcoded to run every 1.0s, NodeTimers are hard coded to
run at every 1.0s. Block mgmt is running every 2.0sec.
However, these timers can be better tuned for both higher and lower
values by server owners. Some server owners want to, and have the
resources to send more packets per second to clients, and so they
may wish to send smaller updates sooner. Right now all ABM's are
coalesced into 1.0 second intervals, resulting in large send queues
to all clients. By reducing the amount of possible timers, one can
get a far better response rate and lower the perception of lag.
On the other side of the camp, some servers may want to increase
these values, which again isn't easily doable.
The global settings abm_interval and nodetimer_interval are set to
current values by default. I've tested with 0.2/0.5 type values
and noticed a greatly improved response and better scattering of
nodetimers, as well as enjoying not faceplanting into doors with
pressure plates anymore.
The legacy init packet (pre v25) sends information about the client's
password that a server could use to log in to other servers if the
username and password are the same. All the other benefits of SRP of
protocol v25 are missed if the legacy init packet is still sent during
connection creation.
This patch adds an option to not send the v25 init packet. Not sending
the v25 packet means breaking compat with pre v25 servers, but as the
option is not enabled by default, no servers are affected unless the
user explicitly flips the switch. More than 90% of the servers on the
serverlist support post v25 protocols.
The patch also fixes a bug with greying out of non compliant servers
being done wrongly, the min and max params were mixed.
Fix two bugs related to the reconnect feature
introduced by commit
3b50b2766aeb09c9fc0ad0ea07426bb2187df3d7 "Optional reconnect functionality"
1. Set the password to the stored one
Before, we have done the reconnect attempt with a
cleared password, so using the feature would only
work if you had an empty password.
Thanks to @orwell96 for reporting the bug.
2. Reset the reconnect_requested flag after its use
the_game only writes to the reconect_requested flag
if it sets it to true. It never sets it to false.
If the flag is not reset after its use, all "reset"s
to the main menu will look like the server had
requested a reconnect.
* No function overloading
* Adhere coding style and with method names following
lowercase_underscore_style
* Use std::string in external API, handling these is
much more fun
Don't excavate the overgenerated stone at node_max.Y + 1,
this creates a 'roof' over the tunnel, preventing light in
tunnels at mapchunk borders when generating mapchunks upwards.
1. Copy-paste error: properly test for back-connection.
In the case of two different connected nodebox types, we want to
assure that if A connects to B, that B also connects to A. This test
was accidentally not implemented correctly.
2. Clear the connects_to_ids before deserializing.
With each new connected node, the deserialization code added more
and more targets to the map, since the map wasn't cleared in between
deserialization steps. This caused e.g. wall blocks to connect to
things in the fence connects_to map.
NDT_CONNECTED attempts to connect to any side of nodes that it can
connect to, which is troublesome for FACEDIR type nodes that generally
may only have one usable face, and can be rotated.
We introduce a node parameter `connect_sides` that is valid for
any node type. If specified, it lists faces of the node (in "top",
"bottom", "front", "left", "back", "right", form, as array) that
connecting nodeboxes can connect to. "front" corresponds to the south
facing side of a node with facedir = 0.
If the node is rotatable using *simple* FACEDIR, then the attached
face is properly rotated before checking. This allows e.g. a chest
to be attached to only from the rear side.
We introduce a new nodebox type "connected", and allow these nodes to
have optional nodeboxes that connect it to other connecting nodeboxes.
This is all done at scenedraw time in the client. The client will
inspect the surrounding nodes and if they are to be connected to,
it will draw the appropriate connecting nodeboxes to make those
connections.
In the node_box definition, we have to specify separate nodeboxes for
each valid connection. This allows us to make nodes that connect only
horizontally (the common case) by providing optional nodeboxes for +x,
-x, +z, -z directions. Or this allows us to make wires that can connect
up and down, by providing nodeboxes that connect it up and down (+y,
-y) as well.
The optional nodeboxes can be arrays. They are named "connect_top,
"connect_bottom", "connect_front", "connect_left", "connect_back" and
"connect_right". Here, "front" means the south facing side of the node
that has facedir = 0.
Additionally, a "fixed" nodebox list present will always be drawn,
so one can make a central post, for instance. This "fixed" nodebox
can be omitted, or it can be an array of nodeboxes.
Collision boxes are also updated in exactly the same fashion, which
allows you to walk over the upper extremities of the individual
node boxes, or stand really close to them. You can also walk up
node noxes that are small in height, all as expected, and unlike the
NDT_FENCELIKE nodes.
I've posted a screenshot demonstrating the flexibility at
http://i.imgur.com/zaJq8jo.png
In the screenshot, all connecting nodes are of this new subtype.
Transparent textures render incorrectly, Which I don't think is
related to this text, as other nodeboxes also have issues with this.
A protocol bump is performed in order to be able to send older clients
a nodeblock that is usable for them. In order to avoid abuse of users
we send older clients a "full-size" node, so that it's impossible for
them to try and walk through a fence or wall that's created in this
fashion. This was tested with a pre-bump client connected against a
server running the new protocol.
These nodes connect to other nodes, and you can select which ones
those are by specifying node names (or group names) in the
connects_to string array:
connects_to = { "group:fence", "default:wood" }
By default, nodes do not connect to anything, allowing you to create
nodes that always have to be paired in order to connect. lua_api.txt
is updated to reflect the extension to the node_box API.
Example lua code needed to generate these nodes can be found here:
https://gist.github.com/sofar/b381c8c192c8e53e6062
The MainMenuManager set the console invisible when a
formspec opened over it, but didn't properly close it,
and the chat console never set itself visible again.
Since commit
3b50b2766aeb09c9fc0ad0ea07426bb2187df3d7 "Optional reconnect functionality"
there is a config option named ask_reconnect_on_crash.
It asks the client to reconnect to the server if the server crashed.
It has been implemeted and works, but due to a function parameter not
being passed it never showed effect. This patch adds the parameter
and fixes the bug.
Also fixes the `reconnect` option of minetest.request_shutdown being ignored.
I've written several experimental bits of code that revolve around the
need for a consistent calendar, but implementing one is extremely hard
in mods due to time changes and mods overriding core.get_timeofday(),
which will conflict.
The second part of the problem is that doing this from a mod requires
constant maintenance of a settings file.
An implementation in core is trivial, however, and solves all of
these problems at virtually no cost: No extra branches in server
steps, and a single branch when minetest.set_time_of_day(), which is
entirely reasonable.
We store the day_count value in env_meta.txt.
The use case is obvious: This change allows mods to create an actual
virtual calendar, or properly account for seasonal changes, etc..
We add a "/days" chatcommand that displays the current day count. No
permissions are needed. It can only retrieve the day count, not
modify it.
Lower water table where base humidity is low.
Alter heat and humidity to compensate for river humidity and altitude
chill.
Correct misuse of surface_max_y in generateTerrain.
Remove sand trails in the water at river mouths.
Remove river water below water_level.
Correct heat/humidity calculations where noises are less than zero.
Correct heightmap errors as much as possible.
Make humidity calculations more readable.
In the calculation of y_start,
when 'column height max' was large it caused
nmin.Y + max_height > nmax.Y - max_height
Now, in this situation y_start is set to the
midpoint between nmin.Y and nmax.Y
Limit y0 and y1 to between nmin.Y and nmax.Y,
otherwise index calculation, which has no checks for limits,
places them at unwanted locations in the voxelmanip
As stated in this forum thread [1], I noticed that there is a
2 second interval in which inventory changes are shown on the
client. @yyt16384 found the source of these 2 seconds:
m_nothing_to_send_pause_timer is set to 2.0 every time there
are no changes to make, but this timer is not reset when
SetBlockNotSent or setBlocksNotSent are invoked. So in worst
case, the changed block will be sent over 2 seconds too late.
With this change, changed inventories are updated almost
immediately, but it causes additional connection load.
This allows mods to perform both asynchronous and synchronous HTTP
requests. Mods are only granted access to HTTP APIs if either mod
security is disabled or if they are whitelisted in any of the
the secure.http_mods and secure.trusted_mods settings.
Adds httpfetch_caller_alloc_secure to generate random, non-predictable
caller IDs so that lua mods cannot spy on each others HTTP queries.
Previously you could steal a secure environment from a trusted mod by wrapping
request_insecure_environment with some code like this:
local rie_cp = minetest.request_insecure_environment
local stolen_ie
function minetest.request_insecure_environment()
local ie = rie_cp()
stolen_ie = stolen_ie or ie
return ie
end
'cam_pos_nodes -/+ box_nodes_d' can exceed the range of v3s16
when a player is near the world edge using a large view range
This previously caused world to disappear
Create new function getBlocksInViewRange() called from
updateDrawList() and renderMap()
Correct code style throughout updateDrawList() and renderMap()
Commit
6a1670dbc31cc0e44178bbd9ad34ff0d5981a060 "Migrate to STL containers/algorithms."
has replaced core::map<T, bool> with std::set<T>, but didn't update
the accompanying comment saying "value is dummy". This happened at
two places.
Introduce a new contentfeatures version (8). When clients
connect using v27 protocol version, they can assume that
the tiledef.backface_culling is trustable, but if clients
connect to servers providing contentfeatures version 7,
then the v27 clients know that backface culling settings
provided by the server in tiledefs are bogus for mesh,
plantlike, firelike or liquid drawtype nodes.
thanks to hmmmm, est31, nerzhul.
Tested on new client - new server, new client - old server
old client - new server.
All places that lock this mutex are only called by the main thread:
ClientMap::updateCamera(), ClientMap::updateDrawList(), ClientMap::renderMap(), ClientMap::renderPostFx().
To avoid spawn search failing in new specialised mapgens
Increase spawn search range to 4000 nodes
Add getSpawnLevelAtPoint() functions to EmergeManager, class Mapgen
and all mapgens
Remove getGroundLevelAtPoint() functions from all mapgens except mgv6
(possibly to be re-added later in the correct form to return actual
ground level)
Make mgvalleys flag names consistent with other mapgens
Remove now unused 'vertical spawn range' setting
Tunnel 3D noises are only calculated when solid terrain is present
in mapchunk, avoiding large amounts of unnecessary calculations
Change 'int' to 's16' in calculateNoise
Change 'i' to 'vi' for voxelmanip indexes for consistency
Keep 'u32 index3d' local to a smaller part of tunnel code
Mgv7: Don't call CaveV7 if no solid terrain in mapchunk
Give 'open' bool a more descriptive name
Replace simple caves with V5 caves, adding unpredictable water and lava
settings and massive caves based on subterrain. Remove fast terrain mode
and accompanying settings. Remove superfluous temperature/humidity
settings. Remove lava/water height setting. Fix errors in humidity
handling and remove humidity_break_point setting. Move cave noises to
generateCaves. Fix minor formatting/naming issues and use
MYMAX/MYMIN/myround.
clock_gettime() is a far better clock than gettimeofday().
Even better than clock_gettime() is that you can select either
CLOCK_MONOTONIC, or even CLOCK_MONOTONIC_RAW. These clocks offer
high precision time. And the _RAW variant will never roll back
due to NTP drift or daylight savings, or otherwise.
I've adjusted this code to select the right clock method auto-
matically based on what's available in the OS. This means that
if you're running a very old linux version, MacOS or other,
you will automatically get the best clocksource available.
I've tested all Linux clocksources by selectively compiling and
running a 10k+ timer test suite. In all cases I confirmed that
the 3 POSIX Linux clocksources worked properly, and were
selected properly.
I've modified the OS X compile path to use the high-res clock
source for all time functions, but I can't confirm it works or
that it compiles.
As for WIN32, I confirmed that the used clocksource is indeed
a Monotonic clocksource, so good news: that code section appears
to be exactly what it should be.
`errorstream` must not be overly verbose as clientside it is directly printed
onto the ingame chat window. These days, the serverlist can contain > 200k bytes,
so better print it to warningstream if the data buffer is too long.
Outdated servers are always sending tiledefs with culling
enabled no matter what, as the value was previously entirely
ignored.
To compensate, we must (1) detect that we're running against
an old server with a new client, and (2) disable culling for
mesh, plantlike, firelike and liquid draw types no matter what
the server is telling us.
In order to achieve this, we need to bump the protocol version
since we cannot rely on the tiledef version, and test for it
being older. I've bumped the protocol version, although that
should have likely happened in the actual change that introduced
the new backface_culling PR #3578. Fortunately that's only 2
commits back at this point.
We also explicitly test for the drawtype to assure we are not
changing the culling value for other nodes, where it should
remain enabled.
This was tested against various pub servers, including 0.4.13 and
0.4.12.
Fixes#3598
Backface culling is enabled by default for all tiles, as this
is how the lua parser initializes each tiledef. We revert to
always using the value from the tiledef since it is always
read and serialized.
Mods that wish to enable culling for e.g. mesh nodes, now can
specify the following to enable backface culling:
tiles = {{ name = "tex.png", backface_culling = true }},
Note the double '{' and use of 'name' key here! In the same
fashion, backface_culling can be disabled for any node now.
I've tested this against the new door models and this properly
allows me to disable culling per node. I've also tested this
against my crops mod which uses mesh nodes where culling needs
to be disabled, and tested also with plantlike drawtype nodes
where we want this to continue to be disabled.
No default setting has changed. The defaults are just migrated
from nodedef.cpp to c_content.cpp.
cloneMesh() has to use a switch in order to create a different
mesh buffer type depending on vertex type. (Credit: the new cloneMesh
was written by RealBadAngel.)
To avoid repetitive code, all other methods use getVertexPitchFromType()
to automatically adapt the indexing to the vertex type at runtime.
The pageflip mode requires a stereo quadbuffer, and a modern graphic
card. Patch tested with NVidia 3D Vision.
The mini-map is not drawn, but that's what is done for topbottom and
sidebyside modes as well.
Also most of the time the user would prefer the HUD to be off. That's
for the user to decide though, and toggle it manually.
Finally, the interocular distance (aka eye separation) is twice as much
as the "3d_paralax_strength" settings. I find this a strange design
decision. I didn't want to chance this though, since it's how the other
3d modes interpret this settings.
Previously, we assumed that reply->str was NULL
terminated. However, this turned out to be not true,
as users reported crashes in strlen connected to
where reply->str was appended to an std::string.
Use the method recomended by the docs, to read the
length separately.
Removing the target file on other platforms was enabled likely unintentionally
by commit 5f1f1151d3a9c113902630adc16cc3f4845da7ba.
This may be the reason why there has been corruption of files on Linux on hard
shutdowns.
Previously I described the problem and this fix in issue #3084.
My commit
e2d54c9f9275e4f77ec33be8054621d42945f7a4 "shutdown when requested from lua in singleplayer too"
broke minetest's feature to connect to servers. The client crashed
after the connection init was complete.
Thanks to @sofar for reporting the bug.
Fixes#3498.
If an `XDG_CACHE_HOME` can't be found or `RUN_IN_PLACE` is enabled,
`path_cache` is left at its default of `$PATH_USER/cache`
(at a time when `PATH_USER` is `..`), rather than being reset to
`$PATH_USER/cache` after `PATH_USER` has been properly set.
This allows other applications (e.g. minetestmapper) to interrogate
the database while minetest is running, without causing an almost
certain minetest crash.
This reverts commit f14e7bac54af65e3d3d99f89f23f114b17058e49.
Reverted due to missinterpretation of agreement, obvious dislike and me not interested in doing fights for feature I don't actually need
This reverts commit 91bafceee6606fab79db1bde4cba01b84fed65c7.
Reverted due to missinterpretation of agreement, obvious dislike and me not interested in doing fights for feature I don't actually need
Previous commit
70ea5d552e283bd5bce3278cbf3819bd87ba2602 "Add support for limiting rotation of automatic face movement dir entitys"
by sapier has broken minetest's feature to open worlds. This was due to a
missing stack pop operation.
Thanks to @oleastre for reporting this bug and suggesting the fix.
3D Mandelbrot/Mandelbar
3D Christmas Tree
3D Mandelbulb
3D Cosine Mandelbulb
4D Mandelbulb
Plus corresponding julia set for each
Add credits for formulas
Rename parameter 'formula' to 'fractal'
Speed optimisations
* Horizontal and vertical are used wrongly. Use height and width because
horizontal/vertical describes different things. Thanks @kilbith for pointing out.
* Update minetest.conf.example and settings_translation_file.cpp
* Correct maximum/minimum copy paste mistake.
Fix the type of the threshold value for mapgen.
The commit
a78dd7f2b6b0e1fefdbaa1ae21b722dd4459e4f4 "Fix spelling of noise_threshold"
has changed it to be read as int, but it can have non-integral values too.
Thanks to @kwolekr for pointing this out.
To terminate unwanted shadows from floatlands or realms above
Also add to LuaVoxelManip calc_lighting for use in mapgen mods
Remove the 2 argument calcLighting, mapgens now use the 5
argument form to specify the volumes for propagateSunlight and
spreadLight
In mgsinglenode replace calcLighting with setLighting and
clean-up use of tabs and spaces
On openSUSE luajit is not detected correctly.
This is because openSUSE is using a lua version suffix, like other Linux distributions do it also.
So the include directory is:
include/luajit-5_1-2.0
A segfault exposed a missing 'vm->m_area.contains()'
check in makeCorridor that allowed the calculation
of vm index for a node outside the vm area. The huge
and invalid index number caused getContent to fail
Fixes bug for which commit
6c37e89f08f962eaba788a31f5d3c798ceaa65e6 "Fix old client showing duplicated health bar on new server"
by @sapier
laid the groundwork, where the server has
updated its copy of the hud flags without
respecting the mask.
Fixes#3395.
Flag is set by default in MapgenParams
The global 'trees' flag remains but is now
undocumented and unset by default in MapgenParams
Add mgv6_spflag 'trees' set by default in
defaultsettings.cpp to affect new worlds only
This is automatically backwards
compatible for existing worlds
* Remove trailing lines from src/sound_openal.cpp
* Don't do a horribly ugly copy of the file's path, allocating and deallocating a
10 kb buffer in the process. This copy was needed for backwards compatibility
with libvorbis 1.3.1 and earlier, as the removed comment explains.
However, even Ubuntu precise has 1.3.2 already. Dropping support and sparing
the ugly copy can therefore be considered safe.
* Actually load sounds from the memory, not caching them at the disk first,
removing the old hack. This is the main motivation for the commit.
Fix regression of commit
5e507c9829942c434a6f1ae7a4f3a488c7e50bef "Add server side ncurses terminal"
which allowed all players, even those without a shout priv, to chat.
Fixes#3362.
Fix regression of commit
5e507c9829942c434a6f1ae7a4f3a488c7e50bef "Add server side ncurses terminal"
where no line termination character was printed after a
lua print outside of terminal mode.
Fixes#3350.
This adds a chat console the server owner can use for administration
or to talk with players.
It runs in its own thread, which makes the user interface immune to
the server's lag, behaving just like a client, except timeout.
As it uses the same console code as the f10 console, things like nick
completion or a scroll buffer basically come for free.
The terminal itself is written in a general way so that adding a
client version later on is just about implementing an interface.
Fatal errors are printed after the console exists and the ncurses
terminal buffer gets cleaned up with endwin(), so that the error still
remains visible.
The server owner can chose their username their entered text will
have in chat and where players can send PMs to.
Once the username is secured with a password to prevent anybody to
take over the server, the owner can execute admin tasks over the
console.
This change includes a contribution by @kahrl who has improved ncurses
library detection.
The Atomic implementation was only partially correct, and was very complex.
Use locks for sake of simplicity, following KISS principle.
Only remaining atomic operation use is time of day speed, because that
really is only read + written.
Also fixes a bug with m_time_conversion_skew only being decremented, never
incremented (Regresion from previous commit).
atomic.h changes:
* Add GenericAtomic<T> class for non-integral types like floats.
* Remove some last remainders from atomic.h of the volatile use.
It isn't possible to use atomic operations for floats, so don't use them there.
Having a lock is good out of other reasons too, because this way the float time
and the integer time both match, and can't get different values in a race,
e.g. when two setTimeofDay() get executed simultaneously.
Cleanup:
* Remove volatile keyword, it is of no use at all. [1]
* Remove the enable_if stuff. It had no use either.
The most likely explanation why the enable_if stuff was there is that it
was used as something like a STATIC_ASSERT to verify that sizeof(T) is not larger
than sizeof(void *). This check however is not just misplaced in a place where we
already use a lock, it isn't needed at all, as gcc will just generate a call to
to the runtime if it compiles for platforms that don't support atomic instructions.
The runtime will then most likely use locks.
Code style fixes:
* Prefix name of the mutex
* Line everything up nicely, where it makes things look nice
* Filling \ continuations with spaces is code style rule
Added operations on the atomic var:
* Compare and swap
* Swap
The second point of the cleanup also fixes the Android build of the next commit.
[1]: http://stackoverflow.com/q/2484980
