10 ms·

OpenTTD Compiled to WebAssembly

343 points by garaetjjte 8y ago

danielvf 8y ago
It even runs on my IOS phone. Incredible!
- llukas 8y ago
  Any idea how battery usage of webassembly version vs native looks like? I'd assume that webassembly would consume more but maybe difference is not significant?
  - astrodust 8y ago
    The original Transport Tycoon Deluxe game was written in assembly so it could run quickly on modest hardware, like a 486 at 50MHz. OpenTTD isn't as efficient, but it's not that demanding either.
    - llukas 8y ago
      Not interested how quick it runs. Just energy expended through native and webassembly.
      - ShinTakuya 8y ago
        How quick it runs to an extent is correlated to energy usage. I know it's not the same but for a single threaded low memory usage game the correlation would be close.
        astrodust 8y ago
        On any given number of cores, sure. The original Transport Tycoon came about before multi-core systems and, as it was DOS based, even threads. Power consumption is a product of cycles plus memory read/write operations.
- Mirioron 8y ago
  It runs on my old android phone too, but I don't think the game is actually playable. I couldn't move the camera around.
  - untog 8y ago
    IIRC you use the right mouse button to drag, so that makes sense.
  - SXX 8y ago
    Actually it's quite playable as soon as you learn UI and used to multi touch that game is using. E.g as far as I can recall you just need 2-finger touch to move camera.
    - Mirioron 8y ago
      Didn't work for me.
kjeetgill 8y ago
For anyone else wondering OpenTTD is Open Transport Tycoon Deluxe.
- mjcohen 8y ago
  Never heard of that before. What occurred to me was "Test to Destruction".
- ncmncm 8y ago
  I wondered too. "OpenTTD is a business simulation game in which players try to earn money via transporting passengers and freight by road, rail, water and air. It is an open-source[2] remake and expansion of the 1995 Chris Sawyer video game Transport Tycoon Deluxe." https://en.m.wikipedia.org/wiki/OpenTTD https://en.m.wikipedia.org/wiki/OpenTTD
  - keyle 8y ago
    It was and is a fantastic game. I played it for many hours growing up. EDIT: the original, Transport Tycoon.
- jodrellblank 8y ago
  See also https://old.reddit.com/r/openttd/ https://old.reddit.com/r/openttd/
db48x 8y ago
I'm surprised at how good the sound is; that's where I've had the most trouble.
- garaetjjte 8y ago
  It's just uses Emscripten SDL2 for audio output. Here's build with MIDI music enabled: https://milek7.pl/openttd-wasm-music/ https://milek7.pl/openttd-wasm-music/
Game_Ender 8y ago
The combination of C++ and OpenGL is really the ultimate in portability. A language supported on almost every platform by one if not more implementations (sometimes 3), coupled with probably the most widely supported graphics API. Of course you lose accessibility, and many platform API conveniences, but you get a more stable and performant platform to work with. In fact it's the platform that most web browser themselves are heavily based on. For another example just look at what Epic was able to do with Fortnite, one code base that literally runs everywhere. Magnum [0] is a favorite of mine for creating portable OpenGL C++ applications. It also has support for compiling to WebAssembly [1] and using WebGL2. 0 - https://magnum.graphics https://magnum.graphics 1 - https://magnum.graphics/showcase/picking/ https://magnum.graphics/showcase/picking/
- ianlevesque 8y ago
  Well, it was for a while: https://www.anandtech.com/show/12894/apple-deprecates-opengl-across-all-oses https://www.anandtech.com/show/12894/apple-deprecates-opengl...
  - Game_Ender 8y ago
    Yeah there is MoltenGL which will probably be open sourced eventually. The real future is Vulkan which is moving to replace OpenGL and for the Apple platforms there is MoltenVK [0] (Vulkan re-implemented on top of Apple's new Metal) which is open source. Magnum has an initial Vulkan backend [1], and many other engines have them or are building them as well. 0 - https://github.com/KhronosGroup/MoltenVK https://github.com/KhronosGroup/MoltenVK 1 - https://blog.magnum.graphics/announcements/2018.10/ https://blog.magnum.graphics/announcements/2018.10/
    - ianlevesque 8y ago
      That’s cool I didn’t realize MoltenVK was maintained by Khronos.
      - AlphaSite 8y ago
goddtriffin 8y ago
Multiplayer functionality doesn't seem to be working for me. Is this just me, or an artifact of the compilation?
- db48x 8y ago
  The browser doesn't provide the usual POSIX api for opening TCP connections. With some work you can write a shim library that implements it in terms of websockets, but it still can't connect to arbitrary hosts. Instead you have to run a proxy server for it to connect to.
  - reubenmorais 8y ago
    Could you use WebRTC instead, for true P2P?
    - db48x 8y ago
      You still need a proxy server, unless the OpenTTD game browser supports WebRTC connections.
      - jeremija 8y ago
        Yeah, you'd need a proxy server (websockets) to establish WebRTC connections. Even after a WebRTC connection is established, you'd need a STUN or a TURN (coturn supports both) server to get around NATs. Pls somebody correct me if I'm wrong!
        tim-- 8y ago
        You should only need a STUN or TURN server if you are attempting to connect to a machine that is behind a NAT. OpenTTD servers are usually on public IPs (similar to HTTP servers), so a STUN or TURN server should not be required. The biggest issue is that WebRTC connections do not allow you to send raw data over TCP or UDP[1]. That being said, it shouldn't be too difficult to just create a WebSocket server that translates between the native network protocol and HTTP WebSockets[2]. [1] https://developer.mozilla.org/en-US/docs/Web/API/RTCDataChannel [2] https://wiki.openttd.org/Network_Protocol
codexon 8y ago
I ran it for a few minutes and then it said: Uncaught RuntimeError: float unrepresentable in integer range at wasm-function[3502]:49 at wasm-function[6940]:395 at wasm-function[6939]:347 at wasm-function[3103]:334 at wasm-function[3284]:30 at wasm-function[4902]:3105 at wasm-function[4903]:654 at wasm-function[8083]:442 at wasm-function[8082]:3 at wasm-function[9782]:13
- antonvs 8y ago
  Looks like there's a bug in wasm-function.
  - jplayer01 8y ago
    I'm not so sure.
- beefsack 8y ago
  You can avoid that issue by using clamp mode when compiling: https://emscripten.org/docs/compiling/WebAssembly.html#trap-mode https://emscripten.org/docs/compiling/WebAssembly.html#trap-...
  - garaetjjte 8y ago
    Thanks, changed that setting.
kwindla 8y ago
Porting c/c++ codebases to WebAssembly is both super fun and frustrating. Network stuff, as mentioned in other comments, is futzy because of the limitations of running in a browser environment. A surprising amount of network code "works," in the sense that it compiles and runs translated to web sockets. (Great work from the WebAssembly and Emscripten community.) But, you know, web sockets. pthreads support landed in Chrome recently: https://developers.google.com/web/updates/2018/10/wasm-threads https://developers.google.com/web/updates/2018/10/wasm-threa... Pipes, select, and unix domain sockets aren't really supported (afaik).
Simple_Guy 8y ago
One of the coolest things to do is go on one of the many multiplayer servers and see some of the super train systems that have been built. 16 lanes high speed rail connecting thousands of nodes.
pjmlp 8y ago
Yep, go Flash. https://en.m.wikipedia.org/wiki/CrossBridge https://en.m.wikipedia.org/wiki/CrossBridge Everything old is new again.
- propelol 8y ago
  It's not a fair comparison. Flash was a closed source non-standard technology.
  - skrebbel 8y ago
    That's not why most people hated it.
    - dcbadacd 8y ago
      But it's part of the reason. It was also notorious for it's security flaws.
      - pjmlp 8y ago
        WebAssembly on its current state still doesn't prevent internal memory corruption, due to lack of bounds checking enforcement. Yes it does not escape the sandbox, however triggering stack corruption of local variables opens the door to explore changing the behaviour of function calls, while getting some goodies in the process. It remains to be seen how secure is WebAssembly at scale, when black hats start actually turning their sights into it.
        tracker1 8y ago
        Given the runtime environment and limitations, I SERIOUSLY doubt WebAsm will be LESS secure than JavaScript's runtime in browsers itself.
      - josefx 8y ago
        One reason I liked flash: You could disable malicious ads with flashblock without breaking 90% of the internet. With the cancerous growth of JavaScript APIs embrancing and extending on all that made flash evil that is no longer possible.
NietTim 8y ago
This is super cool, TTD always has a special place in my heart. Any technical explanation why level generation is so much quicker? Not even a loading screen
- benj111 8y ago
  TTD or Open TTD? TT on my 486 took time to generate a map, (TTD is basically the same code I believe). Open TTD when you've cranked up the map size takes time too. Perhaps you were playing TTD on a relatively powerful pc?
Freak_NL 8y ago
It's a shame the online content functionality isn't working because of a missing zlib library. OpenTTD really has quite an active community of modders and asset creators. You want the trains from your home country? They are available, and probably up to date to the current year. Just download them from within the game, enable them, and start a new game.
neiman 8y ago
It looks amazing, but for some reason it's not polished on my machine. There are many small bugs that don't exist in the native version. For example, when I scroll, the pointer stay frozen till I finish scrolling, and only then "jumps" to the new location. It makes a huge difference between enjoyment and suffering in games.
adhambadr 8y ago
this is really cool. Can't wait for GTA2
- recrof 8y ago
  is GTA2 opensource yet?
  - adhambadr 8y ago
    no but neither TTD, the OpenTTD is a brilliant remake that is based on TTD.
LeanderK 8y ago
Moving the cursor was really sluggish on Safari for the first two to five minutes and afterwards I didn't notice lag. Maybe it's some JIT-compiler warm-up phase?
fs2 8y ago
Really amazing!
vortico 8y ago
Hasn't OpenTTD been ported to JS in 2015? https://epicport.com/en/ttd https://epicport.com/en/ttd Regardless, a WebAssembly port is perhaps more useful since improvements can be merged from upstream more easily.

343 points by garaetjjte 8y ago

danielvf 8y ago

It even runs on my IOS phone. Incredible!

llukas 8y ago
Any idea how battery usage of webassembly version vs native looks like? I'd assume that webassembly would consume more but maybe difference is not significant?
- astrodust 8y ago
  The original Transport Tycoon Deluxe game was written in assembly so it could run quickly on modest hardware, like a 486 at 50MHz. OpenTTD isn't as efficient, but it's not that demanding either.
  - llukas 8y ago
    Not interested how quick it runs. Just energy expended through native and webassembly.
    - ShinTakuya 8y ago
      How quick it runs to an extent is correlated to energy usage. I know it's not the same but for a single threaded low memory usage game the correlation would be close.
      - astrodust 8y ago
        On any given number of cores, sure. The original Transport Tycoon came about before multi-core systems and, as it was DOS based, even threads. Power consumption is a product of cycles plus memory read/write operations.
Mirioron 8y ago
It runs on my old android phone too, but I don't think the game is actually playable. I couldn't move the camera around.
- untog 8y ago
  IIRC you use the right mouse button to drag, so that makes sense.
- SXX 8y ago
  Actually it's quite playable as soon as you learn UI and used to multi touch that game is using. E.g as far as I can recall you just need 2-finger touch to move camera.
  - Mirioron 8y ago
    Didn't work for me.

kjeetgill 8y ago

For anyone else wondering OpenTTD is Open Transport Tycoon Deluxe.

mjcohen 8y ago
Never heard of that before. What occurred to me was "Test to Destruction".
ncmncm 8y ago
I wondered too. "OpenTTD is a business simulation game in which players try to earn money via transporting passengers and freight by road, rail, water and air. It is an open-source[2] remake and expansion of the 1995 Chris Sawyer video game Transport Tycoon Deluxe." https://en.m.wikipedia.org/wiki/OpenTTD https://en.m.wikipedia.org/wiki/OpenTTD
- keyle 8y ago
  It was and is a fantastic game. I played it for many hours growing up. EDIT: the original, Transport Tycoon.
jodrellblank 8y ago
See also https://old.reddit.com/r/openttd/ https://old.reddit.com/r/openttd/

db48x 8y ago

I'm surprised at how good the sound is; that's where I've had the most trouble.

garaetjjte 8y ago
It's just uses Emscripten SDL2 for audio output. Here's build with MIDI music enabled: https://milek7.pl/openttd-wasm-music/ https://milek7.pl/openttd-wasm-music/

Game_Ender 8y ago

The combination of C++ and OpenGL is really the ultimate in portability. A language supported on almost every platform by one if not more implementations (sometimes 3), coupled with probably the most widely supported graphics API. Of course you lose accessibility, and many platform API conveniences, but you get a more stable and performant platform to work with. In fact it's the platform that most web browser themselves are heavily based on. For another example just look at what Epic was able to do with Fortnite, one code base that literally runs everywhere. Magnum [0] is a favorite of mine for creating portable OpenGL C++ applications. It also has support for compiling to WebAssembly [1] and using WebGL2. 0 - https://magnum.graphics https://magnum.graphics 1 - https://magnum.graphics/showcase/picking/ https://magnum.graphics/showcase/picking/

ianlevesque 8y ago
Well, it was for a while: https://www.anandtech.com/show/12894/apple-deprecates-opengl-across-all-oses https://www.anandtech.com/show/12894/apple-deprecates-opengl...
- Game_Ender 8y ago
  Yeah there is MoltenGL which will probably be open sourced eventually. The real future is Vulkan which is moving to replace OpenGL and for the Apple platforms there is MoltenVK [0] (Vulkan re-implemented on top of Apple's new Metal) which is open source. Magnum has an initial Vulkan backend [1], and many other engines have them or are building them as well. 0 - https://github.com/KhronosGroup/MoltenVK https://github.com/KhronosGroup/MoltenVK 1 - https://blog.magnum.graphics/announcements/2018.10/ https://blog.magnum.graphics/announcements/2018.10/
  - ianlevesque 8y ago
    That’s cool I didn’t realize MoltenVK was maintained by Khronos.
    - AlphaSite 8y ago

goddtriffin 8y ago

Multiplayer functionality doesn't seem to be working for me. Is this just me, or an artifact of the compilation?

db48x 8y ago
The browser doesn't provide the usual POSIX api for opening TCP connections. With some work you can write a shim library that implements it in terms of websockets, but it still can't connect to arbitrary hosts. Instead you have to run a proxy server for it to connect to.
- reubenmorais 8y ago
  Could you use WebRTC instead, for true P2P?
  - db48x 8y ago
    You still need a proxy server, unless the OpenTTD game browser supports WebRTC connections.
    - jeremija 8y ago
      Yeah, you'd need a proxy server (websockets) to establish WebRTC connections. Even after a WebRTC connection is established, you'd need a STUN or a TURN (coturn supports both) server to get around NATs. Pls somebody correct me if I'm wrong!
      - tim-- 8y ago
        You should only need a STUN or TURN server if you are attempting to connect to a machine that is behind a NAT. OpenTTD servers are usually on public IPs (similar to HTTP servers), so a STUN or TURN server should not be required. The biggest issue is that WebRTC connections do not allow you to send raw data over TCP or UDP[1]. That being said, it shouldn't be too difficult to just create a WebSocket server that translates between the native network protocol and HTTP WebSockets[2]. [1] https://developer.mozilla.org/en-US/docs/Web/API/RTCDataChannel [2] https://wiki.openttd.org/Network_Protocol

codexon 8y ago

I ran it for a few minutes and then it said: Uncaught RuntimeError: float unrepresentable in integer range at wasm-function[3502]:49 at wasm-function[6940]:395 at wasm-function[6939]:347 at wasm-function[3103]:334 at wasm-function[3284]:30 at wasm-function[4902]:3105 at wasm-function[4903]:654 at wasm-function[8083]:442 at wasm-function[8082]:3 at wasm-function[9782]:13

antonvs 8y ago
Looks like there's a bug in wasm-function.
- jplayer01 8y ago
  I'm not so sure.
beefsack 8y ago
You can avoid that issue by using clamp mode when compiling: https://emscripten.org/docs/compiling/WebAssembly.html#trap-mode https://emscripten.org/docs/compiling/WebAssembly.html#trap-...
- garaetjjte 8y ago
  Thanks, changed that setting.

kwindla 8y ago

Porting c/c++ codebases to WebAssembly is both super fun and frustrating. Network stuff, as mentioned in other comments, is futzy because of the limitations of running in a browser environment. A surprising amount of network code "works," in the sense that it compiles and runs translated to web sockets. (Great work from the WebAssembly and Emscripten community.) But, you know, web sockets. pthreads support landed in Chrome recently: https://developers.google.com/web/updates/2018/10/wasm-threads https://developers.google.com/web/updates/2018/10/wasm-threa... Pipes, select, and unix domain sockets aren't really supported (afaik).

Simple_Guy 8y ago

One of the coolest things to do is go on one of the many multiplayer servers and see some of the super train systems that have been built. 16 lanes high speed rail connecting thousands of nodes.

pjmlp 8y ago

Yep, go Flash. https://en.m.wikipedia.org/wiki/CrossBridge https://en.m.wikipedia.org/wiki/CrossBridge Everything old is new again.

propelol 8y ago
It's not a fair comparison. Flash was a closed source non-standard technology.
- skrebbel 8y ago
  That's not why most people hated it.
  - dcbadacd 8y ago
    But it's part of the reason. It was also notorious for it's security flaws.
    - pjmlp 8y ago
      WebAssembly on its current state still doesn't prevent internal memory corruption, due to lack of bounds checking enforcement. Yes it does not escape the sandbox, however triggering stack corruption of local variables opens the door to explore changing the behaviour of function calls, while getting some goodies in the process. It remains to be seen how secure is WebAssembly at scale, when black hats start actually turning their sights into it.
      - tracker1 8y ago
        Given the runtime environment and limitations, I SERIOUSLY doubt WebAsm will be LESS secure than JavaScript's runtime in browsers itself.
    - josefx 8y ago
      One reason I liked flash: You could disable malicious ads with flashblock without breaking 90% of the internet. With the cancerous growth of JavaScript APIs embrancing and extending on all that made flash evil that is no longer possible.

NietTim 8y ago

This is super cool, TTD always has a special place in my heart. Any technical explanation why level generation is so much quicker? Not even a loading screen

benj111 8y ago
TTD or Open TTD? TT on my 486 took time to generate a map, (TTD is basically the same code I believe). Open TTD when you've cranked up the map size takes time too. Perhaps you were playing TTD on a relatively powerful pc?

Freak_NL 8y ago

It's a shame the online content functionality isn't working because of a missing zlib library. OpenTTD really has quite an active community of modders and asset creators. You want the trains from your home country? They are available, and probably up to date to the current year. Just download them from within the game, enable them, and start a new game.

neiman 8y ago

It looks amazing, but for some reason it's not polished on my machine. There are many small bugs that don't exist in the native version. For example, when I scroll, the pointer stay frozen till I finish scrolling, and only then "jumps" to the new location. It makes a huge difference between enjoyment and suffering in games.

adhambadr 8y ago

this is really cool. Can't wait for GTA2

recrof 8y ago
is GTA2 opensource yet?
- adhambadr 8y ago
  no but neither TTD, the OpenTTD is a brilliant remake that is based on TTD.

LeanderK 8y ago

Moving the cursor was really sluggish on Safari for the first two to five minutes and afterwards I didn't notice lag. Maybe it's some JIT-compiler warm-up phase?

fs2 8y ago

Really amazing!

vortico 8y ago

Hasn't OpenTTD been ported to JS in 2015? https://epicport.com/en/ttd https://epicport.com/en/ttd Regardless, a WebAssembly port is perhaps more useful since improvements can be merged from upstream more easily.