Category Archives: Unity

How to do your Unity builds in the background

If you’ve looked at my recent Unity-related posts and downloaded the projects, you might have noticed I have .bat files like CreateAndUploadWebGLBuild.bat in there to cleanly create final versions easily.

Great.  But if you run this .bat file while you are working on the game with the Unity editor, you’ll get this error:

Aborting batchmode due to failure:
Fatal Error! It looks like another Unity instance is running with this project open.

Multiple Unity instances cannot open the same project.

Ugh.  WebGL builds are especially are incredible slow, so this is a big productivity waster if you’re doing a lot of WebGL testing.  (If you work at a big company and waiting for builds is your favorite time to make coffee and catch up on reddit, well, close this page right now and hope your boss never reads this!)

Cloud Build?

Maybe you could use Unity’s Cloud Build but there are some down sides:

  • Cost $9 a month?
  • Requires that you commit each change to a cvs such as svn, perforce, or git
  • I doubt it can do custom post build commands such as code signing, building a final installer, or rscying files to a linux server and restarting the process.  I guess you could do those things yourself when the build is done, but heck, why not just handle the build yourself from the start.
  • Requires that all your assets are also on cvs (?)

The DIY way

So let’s do it old school with … yep, you guessed it… even more .bat files!  The secret is very simple, Unity will allow you to build in the background if the project directory is different.

You just need to copy your entire project to a temporary folder, then run Unity.exe with parms to do a headless build like normal.

So when you are in a good place with your project and would like to start a background build, hit Ctrl-S to save, then run your “CopyToTempDirAndBuild.bat” file.

After a couple seconds the initial copy is done and it’s safe to continue working while the build is happening in the temp directory – any changes will not be in the temp directory, so your build in progress won’t be affected.  So you can keep working away, without ever closing your main unity editor window.

It’s not especially tricky to do, but here are some .bat files to look at as an example that could be tweaked.

To copy a directory tree to a temp dir: (it assumes the .bat is run from the directory that’s going to be copied)


:this sets some info about the project, for example, it causes %APP_NAME% to hold our main directory name
call app_info_setup.bat

rmdir ..\%APP_NAME%Temp%1 /S /Q
echo Cloning %APP_NAME% to temp dir %APP_NAME%Temp%1...
mkdir ..\%APP_NAME%Temp%1
xcopy . ..\%APP_NAME%Temp%1\ /E /F /Y /EXCLUDE:%cd%\CloneExclusionList.txt

Note:  You may wonder why I’m being repetitive and using “Temp” everywhere instead of including it in a variable.  It’s because you NEVER, NEVER use things like rmdir with only a variable if you can help it, because at some point, that variable is going to be set incorrectly.  It might be  .. or / or something and you’ll delete your whole hard drive.  Safety first.

Another note: %cd% is a DOS trick to get the current full directory

CloneExclusionList.txt contains dirs we don’t want to waste time copying:



:this sets some info about the project, for example, it causes %APP_NAME% to hold our main directory name
call app_info_setup.bat
:Setting no pause causes our .bat files to not do pause commands when they are done
set NO_PAUSE=1
:First, let's customize the directory name we're going to close to, by adding a postfix to make it unique
:Now let's actually make it, we'll pass in the postfix as a parm
call CloneToTempDir.bat %CLONE_DIR_POSTFIX%

:Move to build dir
:Do the actual build
call BuildWebGL.bat
call UploadWebGLRsync.bat
:Move back out of it
cd ..
:Delete the temp dir we were just using

This calls CloneToTempDir.bat with the parm “WebGL” which gets appended to the <AppName>Temp dir.

It then “calls” (this means run another .bat, and come back when it’s done) .bats to create the webgl build and also upload it to the website.

It then destroys the temp directory completely, a good idea because Unity will mark it as the last project and you don’t want to accidently work on that directory later.

Parallel Builds

If you’ve got 16 threads sitting around like I do, it might make sense to build MORE THAN ONE version at a time. (now you see why I use a custom temp dir name for each build)

Apparently, Unity doesn’t care how many simultaneous builds you’re doing on a single computer, as long as its license is valid. (I’m using a pro license)

The key to running parallel builds is to use the “start” command instead of “call”. This means “run this, but instead of waiting, just continue running the rest of this .bat file”.


start BuildAndUploadWebGLInClonedDir.bat
start BuildAndUploadLinux64InClonedDir.bat

So, including the Unity editor you have open, when this is run you’ll have THREE instances of Unity running on the same computer at once.  It all works fine!

Continuous integration as a background operation on the same computer you develop on

If you add a “goto :start” at the bottom of your .bat and a “:start” label at the top, you can “clone and build” non-stop all day.  I don’t see this as very useful as it’s going to break all the time as we’re not doing controlled commits with a cvs but I thought I’d throw that there.

How to get MySQL Connector/Net working with Unity 2017

So you thought my post on networking a few days ago was boring?  Get ready for database fun!

Normally I would just write about what worked, but in this case I’d rather trek through the foggy world of missteps I went through yesterday to make the various errors searchable, maybe my confusion and pain can be of help to some poor future googler.

Why do you want to directly talk to mySQL from a Unity app?

The first thing you normally see when searching online for help with integrating SQL and Unity is “you idiot, it’s too dangerous to ever connect directly to your server database!”

Well, for the CLIENT APP, that’s correct, it’s a horrible idea because anybody can steal your logon credentials and ruin your database. (I love you Team Meat, but … yeah)

Instead, you need a gateway of some kind (for high scores, this is usually a .php page on a website) that can do things like limit score additions from the same day from the same IP address and other types of ‘hardening’.

But for a game server that needs to access lots of data, a direct connection to a database from your Unity-based dedicated server is absolutely vital.

Step 1: Getting the MySQL Connector/Net files

I downloaded the files for “.NET & Mono” and drag and dropped the 4.5 branch files into my Unity project. (spoiler, this was dumb, I only needed one)

Note: Managed .dll files do NOT have to be dragged into any specific folder like C++ plugins do, anything inside of your Assets  folder is ok, even sub-folders.

Step 2: Activating Unity’s 4.5 .Net  support

From inside of Unity, I clicked on one of the newly added .dll files.  Near the bottom of the property window (it’s easy to miss) it gave this message:

“Plugin targets .NET 4.x and is marked as compatible with Editor, Editor can only use assemblies targeting .NET 3.5 or lower, please unselect Editor as compatible platform.”

To fix this, I changed Unity’s scripting runtime version to ‘Experimental .NET 4.6 Equivalent’.

Step 3: Noticing I added the wrong files

I added ‘using MySql.Data;‘ to a .cs as a test.  It compiled, but when I ran the game I got a “TypeLoadException” without any details.  I installed Unity 2017.3.01f (beta) because I heard it gave better description of these kinds of errors, and it did:

TypeLoadException: Could not load type of field 'MySql.Data.Entity.MySqlMigrationCodeGenerator+<>c:<>9__4_0' (1) due to: Could not load file or assembly 'EntityFramework, Version=,'

EntityFramework?  Ohhh, so that zip had multiple versions of MySQL Connector and this one wants EntityFramework, whatever that is.  I removed them all (and the .xml files too) and re-added MySql.Data.dll.

Note: You probably don’t need to update to a beta version like I did; this isn’t recommended usually.  Obviously I just like to live dangerously.

Great, no errors and I can do a ‘using MySql.Data;‘ just fine.

Step 4: Adding support for System.Data

I added ‘using System.Data;‘ as we’ll need that too.  Uh oh, got an error there.  So I dragged and dropped  <unity install dir>\Editor\Data\MonoBleedingEdge\lib\mono\4.6-api\System.Data.dll into my project.  (I’m attempting to use the version that comes with Unity that matches the .NET version I’m using)

Well, it now compiles, but now I’m seeing ‘loading script assembly “assets/plugins/’ failed!’ error in the Unity log.  Is this the wrong version?

The error goes away if I use <Unity dir>\Editor\Data\MonoBleedingEdge\lib\mono\2.0-api\System.Data.dll instead. Fine, I’ll use that. (spoiler, this causes problems later)

I wrote some test code using MySQL Connector, it works fine in the Unity Editor!  I’m able to create/destroy/modify SQL databases. No warnings in Unity either!  But uh oh, now I’m seeing this in Visual Studio:

warning MSB3277: Found conflicts between different versions of the same dependent assembly that could not be resolved.".

I guess Visual Studio is set to use a newer version and having the old System.Data.dll referenced is bad?

Not only that, but when I build a Win64 stand-alone version, when running it, I got this error:

NullReferenceException: Object reference not set to an instance of an object
 at MySql.Data.MySqlClient.MySqlPoolManager.GetKey (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x00012] in <861c41359f7d4496a8fdf269ae744290>:0 
 at MySql.Data.MySqlClient.MySqlPoolManager.GetPool (MySql.Data.MySqlClient.MySqlConnectionStringBuilder settings) [0x00000] in <861c41359f7d4496a8fdf269ae744290>:0 
 at MySql.Data.MySqlClient.MySqlConnection.Open () [0x0016d] in <861c41359f7d4496a8fdf269ae744290>:0 
 at RTSqlManager.Init (System.String serverIP, System.String userName, System.String userPassword, System.String databaseName) [0x00083] in F:\Unity\SQLTest\Assets\RT\MySql\RTSqlManager.cs:51 
 at SQLTest.Start () [0x00030] in F:\Unity\SQLTest\Assets\_Script\SQLTest.cs:64

Uh… ok, I guess I used the wrong version of the .dll or something, I can see it’s being included but … when I look around, I can see other .DLL’s are coming from directory is actually from <Unity dir>\Editor\Data\MonoBleedingEdge\lib\mono\unityjit and not where I took them from.  Using the System.Data.dll from this “unityjit” dir fixed the Visual Studio warning AND fixed the standalone versions (Win and Linux at least, that’s all I tested).

It works!  So is it fast?

Hallelujah! Everything runs ok, both local in Windows (to test this, you need to setup a MySQL server on Windows) and on linux.  (I’m actually using MariaDB, a MySQL fork, that works fine too)

Speed seems comparable to using the C++ version.  As is my way, I wrote a Unity app with built-in Telnet server to test speeds, here are the results on a dedicated linux server:

Command > ?
/? for help
/create to create testtable
/delete to remove testtable
/add <count> to add a bunch of records
/show <index> to look at a specific record
/stats to show current status of testtable and record count
/seektest <count> to benchmark loading <count> random accounts and reading ID and RandomNum from them
/updatetest <count> to benchmark updating <count> random accounts with a new RandomNum and RandomIndexedNum
/ranktest <count> Rank, benchmark, and view top <count> records

Command > /updatetest 1000
Updating RandomNum and RandomIndexedNum for the first 1000 accounts, each in a different SQL statement
Updated 999 accounts in 5.860773 seconds. (0.005860773 p/account) (time taken: `w5.869883 seconds``)

Command > /seektest 1000
Reading ID and RandomNum for 1000 random accounts in 1000 different SQL SELECT statements...
Read from 1000 accounts in 0.1809998 seconds. (0.0001809998 p/account)
 (time taken: `w0.1875515 seconds``)

Command > /ranktest 1000
Ranking top 1000 random numbers...
#1 ID: 50117 RandomNum: 1999986
#2 ID: 31319 RandomNum: 1999854
#3 ID: 5009 RandomNum: 1999835
#4 ID: 7211 RandomNum: 1999784
#5 ID: 40406 RandomNum: 1999772
#6 ID: 9686 RandomNum: 1999698
#7 ID: 18099 RandomNum: 1999644
#8 ID: 41235 RandomNum: 1999593
#9 ID: 12447 RandomNum: 1999505
#10 ID: 37578 RandomNum: 1999396
(not displaying the rest...)Took 0.02680588 to rank and get 1000 records.
#1 ID: 35 RandomIndexedNum: 19954265
#2 ID: 552 RandomIndexedNum: 19942897
#3 ID: 161 RandomIndexedNum: 19898997
#4 ID: 874 RandomIndexedNum: 19872310
#5 ID: 484 RandomIndexedNum: 19859544
#6 ID: 453 RandomIndexedNum: 19777522
#7 ID: 649 RandomIndexedNum: 19776457
#8 ID: 851 RandomIndexedNum: 19769359
#9 ID: 488 RandomIndexedNum: 19741107
#10 ID: 727 RandomIndexedNum: 19711418
(not displaying the rest...)Took 0.0008430481 to rank and get 1000 indexed records.
 (time taken: `w0.02984619 seconds``)

To break it down (note: this database has 50,000 records):

Update a record: 5 ms

Seek and read from a random record: 0.18 ms

Sort 50k unindexed ints and return the top 1000:  27 ms

Sort 50k indexed ints and return the top 1000:  0.84 ms

Final thoughts

Well, I probably should have created the table with ENGINE=MEMORY as I suspect the update record test was hampered by IO writeback (this system doesn’t have an SSD), but overall I’m happy with these speeds.

I wonder how the speeds would compare with SQLite? Is the fact that I’m using a beta version of Unity change/break anything I did?  I don’t know, but it works fine now so whatever.

Stress testing Unity’s LLAPI, what are the limits?

NetTest – a tool for stress testing the LLAPI, full Unity project download at the bottom!

Update 2/27/2020:  Don’t use LLAPI, Unity is going to stop working on it at the end of 2020 so you’ll be screwed I guess. 

Luckily their replacement netcode isn’t ready yet so now you don’t know what to do except maybe try third party libraries or use simple TCP sockets.  Thanks, Unity

Seth, what the hell do you know about netcode, anyway?!

Woah, with the attitude already.  Look, I’m all about multiplayer.  Have been for a long time.  I’ve gone from being excited to get two people walking on the same ANSI map in LORD2 in the early 90s to hitting the 70,000 concurrent user mark during busy times in Growtopia.

In addition to writing my own junk, I regularly play with Unity and Unreal and am constantly trying to see how they can fit my developing style – mostly I need them because it’s becoming a losing battle to try to maintain your own 3D engine if you also want to actually design and release games too.

What’s LLAPI, anyway?

LLAPI stands for Low Level Application Programming Interface.  It’s what Unity’s HLAPI (High level) API is built on.  I guess both of those can be called part of UNet. (Unity networking)

Why not just use the HLAPI like a normal person?

That might be ok for some projects, especially round-based networked games without too many players.

When you are targeting MMO level network performance where a server may have to track stats of millions of players and simulate a world for weeks instead of minutes, the first rule is:

Stay as low level as you reasonably can. 

I don’t want someone else’s net code to even think about touching my gameobjects, I just want it to deliver reliable/unreliable packets that I write/read straight bytes to.  That’s it.  I want to handle things like prediction, dead reckoning, and variable serialization, myself!

What’s the deal with UDP, TCP, and WebSockets?

Both UDP and TCP are internet protocols built on top of IP.

TCP is a bidirectional socket based connection that insures your data is correct and sent in the right order.

It’s like calling Jeff, he picks up the phone and you can both talk until one of you puts the phone down.  Oh, and after you say something, you make sure Jeff understood you correctly each time, so that eats up a bit of time.

UDP is is a stateless connection where single packets get sent.  You write your message on a rock and throw it at Jeff’s window.  While it gets there fast, it’s possible you’ll miss and Jeff will never see it. If dozens of people are throwing rocks, he needs to examine each one carefully to figure out which pile to put it with so the text is attributed to the right thrower.  He might read the second rock you threw before the first one.

WebSockets are basically TCP with a special handshake that’s done over HTTP first.  To continue this already questionable analogy, it’s as if you had to call Jeff’s mom for permission, and then she gave you his cell number to call.

In theory WebSocket performance could be similar to TCP but in practice they are much slower and unreliable, I don’t really know why but hey, that’s what we get.  I suspect this will improve later.

For games, UDP is nice because you can send some of your packets fast with no verification that they were received, and others (more important packets, like dying) with verification which sort of makes those packets work like TCP.

That said, most games probably would be ok with a straight TCP  steam as well and having a connected state can make things easier, like easily applying SSL to everything and not worrying about unordered packets.

Why use WebSockets instead of UDP or TCP? Just use UDP or TCP for everything, moran

BECAUSE I CAN’T!  Browsers won’t allow the Unity plugin to run anymore, they just allow straight javascript/WebGL these days.  It hurts.  I mean, I wrote a cool multiplayer space taxi test for Unity using TCP sockets and now nobody can even play it.

What does LLAPI use?

It can read from both sockets (UDP) and WebSockets at the same time and route them so your game can let them play together.  But how fast is it, and does it work?

This brings us to the second rule of netcode:

Use stress tests without game code to notice glaring problems early and more clearly

Which finally brings us to the point of this post.  NetTest is a little utility I wrote that can:

  • Run as a client, server, or both
  • If you connect as “Normal client” you can all chat with eachother
  • Run with a GUI or as headless (meaning no GUI, which is what you want for a server usually)
  • Can open “Stress clients” for testing, a single instance can open 100+ clients sockets
  • When stress mode is turned on, the stress clients will each send one random sentence per second.  The server is set to re-broadcast it to ALL clients connected, so this generates a lot of traffic.  (300 stress clients cause the server to generate 90K+ packets per second for example)
  • Server can give interesting stats about packets, payload vs Unity junk % in the packets, bandwidth and server speed statistics
  • Built in telnet server, any telnet client can log on and get statistics directly or issue commands
  • Tested on Windows, linux, WebGL
  • Supports serializing variables and creating custom packet types, although the stress test only uses strings
  • Everything is setup to push performance.  Things that might mess with the readings like Unity’s packet merging or modifying values based on dropped packets is disabled.  All processing is done as fast as possible, no throttling or consideration to sleep cycles.
  • Keep in mind a real game server is going to also being doing tons of other things, this is doing almost nothing CPU wise except processing packets.  Testing things separately like this make it easier to see issues and know what the baseline is.


These tests are presented ‘as is’, do your own tests using my Unity project if you really want exact info and to check the settings.

My windows machine is a i7-5960X, the remote linux box is similar and hosted on a different continent, I get a 200 ping to it.

All packets in NetTest are being sent over the ‘reliable’ channel.  No tests involve p2p networking, only client<>server.


config.AcksType = ConnectionAcksType.Acks32; //NOTE: Must match server or you'll get a CRC error on connection
config.PingTimeout = 4000; //NOTE: Must match server or you'll get a CRC error on connection
config.DisconnectTimeout = 20000; //NOTE: Must match server or you'll get a CRC error on connection
config.MaxSentMessageQueueSize = 30000; 
config.MaxCombinedReliableMessageCount = 1;
config.MaxCombinedReliableMessageSize = 100; //in bytes
config.MinUpdateTimeout = 1;
config.OverflowDropThreshold = 100;
config.NetworkDropThreshold = 100;
config.SendDelay = 0;


Ok, here I’m curious how many bytes LLAPI is going to use with clients doing nothing.

Server is set to localhost.  I’ve got 4 NetTest’s running – the one on the bottom right has had “Start local host” clicked, and the three others each have added 100 stress clients.


  • Around 30 bytes per stay alive packet per client.  (23KB total over 7.74 seconds, sent 2.2 packets per client over 8 seconds, so roughly what I would expect for the 4000 ms ping timeout setting)  Are stay alives sent over the reliable channel?  Hmm.
  • Adding and removing test clients is a blocking operation and gets progressibly slower as more are added – why does it get slower and cause my whole system to act a bit weird?
  • While closing the instances looks normal, the instances are actually spending an additional 30 seconds or so to close sockets that were opened
  • Side note: Having a client ping the host (at localhost) takes about 2 ms.  (normally this would be bad, but given that it can’t check until the next frame, then once more to get the answer, this seems to match the framerate decent enough)

I’m not going to worry about the socket slowness, this may be related to a windows 10 resource thing.  I’ll launch with less clients in future tests to help though.  The server itself has zero speed/blocking issues with actually connecting/disconnecting though, so that’s good.


Ok, now we’re getting serious.  I have 5 instances – 4 have 50 stress clients, 1 is the server.  (I could have run the server on one of the stress client instances, but meh)

First I enabled 50 clients in “stress mode” – this should generate 10,000 packets (50*200) per second.  The server gets 50 lines of text from clients, then broadcasts each one to each of the 200 clients.  Huh, stats show it only sending around 6,000 packets per second, not 10,000.  However, we can see all the lines of text are being delivered.

That seemed fine so I upped it to all 200 clients doing the stress test – this should cause the server to send 40,000 packets a second (and receive 200 from the clients).

The stats show only 24,549 packets and 5.3 MB per second being sent. About 15% is unity packet overhead, seems like a lot but ok.  Server FPS is good, slowest frame was 0.02 (20 ms) so not bad.

Is unity combining packets even though I set config.MaxCombinedReliableMessageCount = 1; ?  Oops, I bet that needs to be 0 to do no combining.

I also notice 4,346 per second packets being received by the server.  200 for my messages, and I assume the rest are part of the “reliable guarantee” protocol they are doing for UDP where the clients need to confirm they received things ok.  Oh, and UNet’s keep alives too.

In the screenshot you can see an error appearing of “An abnormal situation has occurred: the PlayerLoop internal function has been called recursively… contact customer support”.  Uhh… I don’t know what that’s about.  Did I screw up something with threads?  It didn’t happen on the server, but one of the four client instances.

I let it run at this rate for a while – a few clients were dropped by the server for no reason I could see.   Not entirely stable at these numbers I guess, but possible it would be if I ran it on multiple computers, it’s a lot of data and ports.


As nice as it is to be able to turn on both the server (localhost) and the client directly from the same app in the Unity editor to test stuff, eventually you’ll probably want to get serious and host the server on linux in a data center somewhere.  This test let’s us do that.

I’ve changed the destination address to the remote IP. (You can click the GameLogic object to edit them, I was too lazy to make a real GUI way))

I have a .bat file that builds the Unity project (on Windows) and copies it to the remote server, then triggers a restart.  It’s run on Linux like this:

cd ~/NetTest
chmod +x ./linux64headless
./linux64headless -batchmode -nographics -logFile log.txt

Here is a screenshot of the 100 clients (using one instance of NetTest) connecting to the linux server (which is also NetTest) (And no, that’s not the real port/ip, stop trying to hack me, Mitnick)

So let’s try to digest this data.

  • NetTest Client: The 100 clients are self reporting receiving about 1,150,000 (1.15 MB) bytes of actual payload data per second. (10000 lines of text).  Zero packets in the send queue
  • Windows system: Windows says 12.1 Mbps per second, so 1.5 MB, close enough, who knows what else I’m streaming/downloading
  • Linux system: iotop shows server sending 10.Mb (1.25 MB per second) so that seems right
  • Linux NetTest: (using telnet) it’s reporting it’s sending 1.22 MB per second (only 3,458 packets per second, yeah, definitely some packet merging happening)  The total stats went negative, I ran this a while, uh… I guess I need to be using larger numbers, probably rolled over.
  • Linux: Server is running at 1100 FPS, so zero problems with speed.  You’re probably thinking “Hey, it’s headless, what do you mean frames per second? What frames?”, ok, fine, it’s really measuring “update()’s per second”, but you know what I mean.  Slowest frame out of the 90 second sample time was 0.0137 (13 ms)
  • I don’t have it in the screenshot, but top shows the server is not too power hungry, its process seems to use 3% (no load) to 15% (spamming tons of packets).  Keep in mind we aren’t actually DOING anything game related yet, but for just the networking, that isn’t bad

I tried 200X200 (4x the total bandwidth & packets, so 5 MB a second) but the outgoing packet queue started to fill up and I started dropping connections.


I’m not going to bother making pics and somehow this post already got way out of control, but here is what seemed to be the case when I played with this earlier:

  • No WebSocket stats are included in the stuff UNet reports – “the function called has not been supported for web sockets communication” when using things like NetworkTransport.GetOutgoingFullBytesCountForHost on it
  • WebGL/WebSockets be slow.  Real slow. If pushed the bandwidth to over 18KB per second (per Chrome tab), packets started to get backed up.  I don’t know if things are getting throttled by the browser or what.  The server eventually freaks out when the send queue gets too big and starts throwing resource errors.
  • When creating stress test clients, a single WebGL tab seems limited to 14 WebSockets max (Chrome at least)
  • I suspect there could be issues with a naughty WebSocket filling up the queue and not sending acknowledges of receives, your game probably needs to carefully monitor packets sent/received to disconnect people quick if they abuse the connection
  • WebSocket queue/etc issues don’t affect or slow down normal connections, so that’s something
  • Mixing WebSocket and normal Sockets (UDP) clients work fine, that’s a very handy thing to be able to do

Final thoughts

All in all, I think directly using LLAPI in Unity 2017.1+ is promising.  Previously, I assumed I’d need to write my own C++ server to get decent socket performance (that’s how I did the Unity multiplayer space taxi demo) but now I don’t think so, if you’re careful about C#’s memory stuff.


  • How is it ok that Unity’s text widget/scroller can only show like 100 lines of text? (65,535 vert buffer errors if you have too much text, even though most of it is off screen)  Maybe I’m doing something wrong
  • Unity’s linux builds don’t seem to cleanly shutdown if you do a pkill/sigterm. OnApplicationQuit() does not get run, this is very bad for linux servers that could restart processes for reboots or upgrades. (if it’s a dedicated server you can work around it, but still!)
  • WebGL builds can’t do GetHostAddresses() so I had to type the real IP in for it to connect (I should try switching to the experimental 4.6 net libs)
  • To my great surprise, my telnet host contined to run and send answers even after stopping the game in the editor.  How could that game object still exist?! Threads and references are confusing, I fixed it by properly closing the telnet host threads on exit.
  • The Unity linux headless build worked perfectly on my CentOS 7.4 dedicated server, didn’t have to change a single thing
  • It’s weird that you’ll get CRC errors if PingTimeout/AcksType/DisconnectTimeout don’t perfectly match on the client and server. I wonder why there is not option to just let the server set it on the client during the initial handshake as you want to be able to tweak those things easily server-side.  I guess the client could grab that data via HTTP or something before the real connect, but meh.

NetTest download

Download the NetTest Unity project with full source here

Note:  I left in my .bat files (don’t mock the lowly batch file!), thought they may be useful to somebody.  They allow you to build everything for linux/win/webl, copy to the remote servers and restart the remote server with a single click.  Nothing will work without tweaking (they assume you have ssh, rsync etc working from a dos prompt) but you could probably figure it out.

Source is released under the “do whatever, but be cool and give me an attribution if you use it in something big” license.

The Last E8 postmortem (LD39) and some Unity vs UE4 thoughts

Presenting, the crappy game title I made! Akiko’s comment was “I didn’t know you were going to show my model up close, ugh”

The Last E8 Postmortem

Last weekend was the triannual Ludumdare game jam.  If you don’t know what that is, it’s a masochistic ritual where you voluntarily force yourself to create a new game over a weekend and publish it for all to see.

Akiko pressured me into it as she wanted to Blender up some things for practice.  I acquiesced to be her programming partner if we could come up with something to match the theme.

The LD theme announced was “Running out of power”. This was 10 AM our time.

The Idea Phase

We agreed to think up some ideas and exchange them at lunch.  So in a Kyoto thai place Akiko showed me her idea:

Hmm.  I don’t know what to say about that except, I like it.  Something about being an employee who has to manage his drug use to stay productive.  (for the record, RTsoft does not endorse the use of illegal narcotics.  I do however, endorse the world’s favorite stimulant, coffee.)

As for myself, I didn’t have much except a vague concept of celebrating the Tesla Model 3’s release with a game based on it somehow.  3D flying game?

So we starting working on Akiko’s idea – resolutely requiring that we completely nail down the game mechanics in photoshop or on paper before even starting.

I figured there were two possible ways to take this:

  • Lemonade Stand style: Strategic choices made, some kind of turns system. Mostly buttons and clicks.
  • Cookie Clicker style: Also buttons and clicks, no real strategy but slowly building up your empire. (I’m playing as I write this article.  Whee!)

I was appalled to find Akiko wasn’t aware of either game. You think you know somebody.

I decided “Cocaine Clicker” was the way to go simply because I liked the name and according to google it wasn’t taken.

Side note: I always google names because if I don’t, people will think I copied something else.  I sort of miss pre-internet days where you could just be original without caring if people thought you weren’t original.

Theme problems

I did some photoshop mockups of the buttons and tried to map out some gameplay.

Unfortunately “Running out of power” didn’t really match what I’d designed; the concept of running an office, buying more employees and managing their illicit substance needs just didn’t work with it.

A fundamental problem is you never run out of anything in a classical clicker game, you only gain.

I did like her idea of a split screen, half being the office, and half being the drug farm/factory. Sort of two games in one with a symbiotic relationship between them required for survival.

Engine problems

As I mulled this over I fired up my game engine for the first time.  I decided to use UE4 as that’s what I’ve had in my head in recently for some VR tests.  (If you have a Vive, please try my tech demo later!)

Lo and behold, UE4 was cursed.  I had setup a basic C++ UE4 project but was plagued by crashes and bugs.  I mean, I hadn’t even written any real code yet.

The worst of it was the silent errors.  Sometimes something internally was broken that caused a setting to be grayed out that shouldn’t be.  I feel like the only way to be safe is basically restart the editor after every C++ class is added or a blueprint is reparented. Slow.

Those issues are WORSE than a simple crash, because until it occurs to you to restart, your progress is entirely obstructed for unknown reasons.  I thought I had done something wrong, when I hadn’t.

Knowing I probably had less than a day of total time to throw at this, I said screw it and used this jam as a chance to try out Unity 2017.  (I’d used Unity 5 last year but forgot everything)

I have to admit, Unity is nice.  The MS Visual Studio 2017 integration is fantastic these days. Zero crashes.  Breakpoint debugging worked immediately with no hoops to hop. Goodbye forever, MonoDevelop.

I’m constantly switching back and forth between these two engines (plus my own homegrown one for 2D and simple 3D)  so I’m going to pause for a second and show my current engine scorecard in this middleware battle royale.

Seth’s Unity VS UE4 scorecard:

Unreal Engine 4:

  • Allows real C++ so the last twenty years of code doesn’t feel wasted
  • Actually using that C++ causes editor glitches non-stop and longish compile times
  • I think it’s faster overall and easier for me to replace the networking code with my own
  • I don’t like the royalty scheme.  Being legally required to calculate royalties for eternity (assuming your game makes anything) is awful
  • Blueprints may seem ok at first, but they are actually the spawn of satan as soon as you need to do anything slightly tricky.  Go ahead, write Vector3 vFinal = (vDir +vOffset).Normalize()*speed*dragMod); in BP, see what a mess that looks like. Now cut and paste it into a new entity and get forced to recreate and reconnect all the variables involved.
  • Forced to choose between overly simplistic BP or slow compiling C++
  • HTML5 support is questionable, doesn’t seem to be a priority.  Huge file sizes, rendering problems
  • Full source code.  Makes this a good choice if you’re going to be implementing your own streaming landscape or enet networking.


  • No C++.  C# isn’t bad, but I miss my direct pointer manipulation and huge library of code I’ve written, so it means a lot of porting, or using plugins that are less portable.
  • Compile times are a dream
  • No crashes, was 100% stable (so far, anyway)
  • Better 3D import options, it can handle .blend files directly
  • Better audio import options too, unlike UE4 it can properly handle a simple .mp3 file
  • Excellent HTML5 support – nearly a must for a public game jam, more on this later
  • Month to month licensing isn’t cheap for the Pro version, but at least they don’t have their hooks on your game royalties for eternity.  Free version isn’t bad either really
  • No source code (well, not for peons like me, anyway)

So in the end, I’m thinking I’m around 5X faster when using Unity simply because of faster compiling and smarter import options.  I guess I need to do a VR demo in Unity and test that side of things too though.

Screw it, let’s use Unity

In the end I told Akiko, look, I’m switching engines so how about I do a sort of simple 2D flying game as a refresher for me.

“Can I still make 3D models in blender?”


“Ok, I’m in.  What will the game be like?”

“It will be like The Last V8 crossed with Space Taxi”

“Never heard of those”

The Last V8:

Space Taxi:

Using Unity’s auto collision

I remembered this trick from when I made Multiplayer Space Taxi a while ago, you can very easily add collision to a level simply from an image.

Unity’s magical Polygon Collider 2D component

About HTML5 vs native with game jams

Because this is my main development machine, long gone are the days where I can run unsigned binaries from people I don’t know.  I know, I hate that, but unless I setup a clean or virtual machine that’s just how it is.

Play our game

So finally, here is the game we made.  True to its heritage, it’s extremely hard.  Good luck!

Play the game in your desktop browser here

Unity project/source code here

(also, the LDJAM site link for it is here)

Dev Diary: A look at Visual Studio 2013, Unity, and UnityVS


I’m a bitter old man

When you’ve been making stuff as long as I have you get comfortable with your tools.

I am a greased ninja with Visual Studio 2005, VisualAssist, and C++.

I’m a snail drenched in chunky peanut butter working with anything else.

But yesterday I gave Visual Studio 2013 + Unity a shot and it actually wasn’t half bad, so here are my tips if that’s something you’re interested in.  Beats MonoDevelop by a mile as far as I can tell.

My tips for people upgrading from old VS versions:

  • First I downloaded Visual Studio 2013.   I guess it’s “Ultimate” and free for 90 days?  Fine.  After that we’ll see, but I’m pretty sure I’m not going to cough up $13,299 for Ultimate!
  • Set keys to the included VS 2005 layout.  Changed it so F7 will compile all.
  • MOST IMPORTANT: Enabled Options->Environment->Tabs and Windows->Floating tab wells always stay on top of the main window.  Without this I found VS 2013 totally unusable.
  • Turned off the silly all upper case menu fonts
  • Installed Productivity Power Tools 2013 (adds some stuff to make the IDE smarter, sort of like VisualAssist?)
  • Oh God, what are these vertical lines connecting every matching brace?!  Disabled that, FAST.
  • Stopped it from showing “References”
  • Turned off its funky new scroll bars, but ended up turning them on again, gotta see how that feels, they do have some interesting data
  • Installed UnityVS (MS did something very smart, they bought it and made it free)
  • Imported the “Visual Studio 2013 Tools.unitypackage” into a simple Unity project (this file gets installed by UnityVS  into C:\Program Files (x86)\Microsoft Visual Studio Tools for Unity\2013 or something, have to dig for it)
  • Inside Unity I double clicked a source code file and viola, it did load the project in VS 2013!  It wouldn’t start the Unity project when I hit F5, but it did connect to the process, so after manually starting the game in Unity it did perform debugging fine.  I think Visual Studio has THE BEST debugger around so this should come in handy.  Er, I mean, I’m guessing, since my code never has bugs of course. <awkward silence and then someone coughs in the back>
  • When you hit a breakpoint, the Unity editor side seems to completely freeze until you hit Resume, too bad, seems like it would be useful to tool around in there and look at objects during debugging.
  • Anyway, everything works and doesn’t feel half bad.  So far.  I assume the crashing,  freezing, and constant reboots that also plagued my experience with MonoDevelop/Unity will start soon though.

Anyway, here’s a picture of what debugging looks like.  I think it would be handy to be able to write non-Unity specific C# code and simultaneously have Unity and non-Unity VS projects open using it, maybe C++ as well as I still like that for my server backend code.  (See my Space Taxi Multiplayer test)  (Uhh, ignore that code in the screenshot, it’s uh, an exercise for the reader to figure out how to make that less stupid looking and redundant)