Setup Spacedesk to create multiple virtual monitors

How can you get up to two additionnal virtual screens without paying for new monitors or a ghost dongle? Read this guide to find out!

No longuer works

Unfortunately, this guide no longuer works due to changes in the SpaceDesk client. These changes prevent you from connecting to the server directly if it is running on the same computer.

To bypass this, you have only three options:

• You can use the HTML5 client with 127.0.0.1. This has the limit of allowing only one additionnal screen because you can't connect two HTML5 clients (the server will deny it)
  
• You can make the client think you are connecting to another computer (and the server thinking it's coming from another computer) by routing your connection via a special rule on your router / firewall (which is what I'm doing). This rule, if done properly, will not expose SpaceDesk to the Internet. Unfortunately, as far as I know, this requires a router with an advanced firewall (for NAT rules), which is not commonly sold in store
  
• You can use another computer (even in a VM) or your phone

If anyone find a better way, please leave a comment below so I can add it here.

Introduction

Bigscreen is an awesome app for virtual reality that supports up to three monitors that you can use within the VR environment. But what if you don't own two other monitors? Can you still use the multi-monitor feature?
Well, the answer is a big YES! With the help of the Cinema Update Update (Bigscreen Beta "CINEMA UPDATE UPDATE" v. 0.17.1 is rolling out today with bug fixes) and spacedesk[www.spacedesk.ph] (or any other software that can do it), you can add up to two additional screens to Bigscreen for free!

Note that the following guide works only on Windows 10 and require admin rights! Windows 7 support of spacedesk is still experimental and have not been tested with Bigscreen.

Installing Spacedesk

The first thing you need to do is to install both the Spacedesk server (includes the driver) and viewer. To get started, download both from the Spacedesk download[spacedesk.ph] page, then follows these simple steps:

• Start the server installer by double-clicking it
  
• Accept the admin / UAC prompt (if needed)
  
• Click Next
  
• Read and Accept the agreement then click Next twice
  
• Uncheck Add an exception to the Windows firewall for spacedesk unless you would like to use another device as a viewer in the future
  
• Click Next then Install
  
• Click Finish when the install is complete

The server is now installed and running (you can confirm it by looking at your task bar. A new icon have been added). We now need to install the viewer software. This is basically a client that will connect to the server and display the new monitor. You can install it on any devices you would like to use as an external monitor.

• Start the viewer installer by double-clicking it
  
• Accept the admin / UAC prompt (if needed)
  
• Click Next
  
• Read and Accept the agreement then click Next twice then Install
  
• Click Finish when the install is complete

Configuring and starting the viewer

Now that we got both the server and the viewer installed, we can start using spacedesk and create virtual monitors!

First, start the viewer by double-clicking on the spacedesk Windows VIEWER icon on the desktop. Then go in Settings -> Compression quality. Set everything to the lowest value, just like in the screenshot below then click OK


By default, the viewer will create the new monitor with the native screen resolution of your computer. This might be fine for most of the users, but some may want a smaller or larger one. You can change the resolution in Settings -> Resolutions.... If you would like to use a different one, make sure to uncheck Native Screen Resolution then select the resolution you would like to use and click Apply.
Note that you can't change these settings while the viewer is connected to the server so you will have to disconnect it, change them and reconnect.


Now, go in File -> Connect... (or use the shortcut CTRL + SHIFT + C) to open the Connect window. Click on the Manually enter IP address button and enter the IP 127.0.0.2 then OK. The 2 is important because 127.0.0.1 and localhost (if entering a hostname instead of the IP) are blocked in the code, but not the other IPs in the private 127.0.0.0/8 loop-back range.
We now see that our IP has been added to the list of found servers. We can therefore click on OK connect! to connect the viewer and add the new screen. And... that's it! The new monitor have been added and we can see the desktop in the viewer! You can now minimize it as you won't need it until you want to remove the monitor. To disconnect, you can either close it or go in File -> Disconnect.

If you would like to add a third monitor, just redo the steps above. You can also use a different resolution for any new monitor you add by changing the resolution setting.

Start Bigscreen and configure the monitors

Now that we have our monitor(s) connected, we can start Bigscreen and configure / adjust them the way we want!
To do this, simply launch Bigscreen, put your headset on and select Customize your screen on the the tablet interface to adjust to your liking. Could it be easier?

Later, if you rebooted or closed the viewer(s) and would like to get more monitors again, simply restart the viewer and connect it. It should have remembered the IP we added as well as any other settings that were changed.

That's it!

Setting up multiple monitors in Bigscreen normally requires multiple physical ones, but with spacedesk you can do the same thing for free!

You can also use Spacedesk with other devices to get more physical monitors connected to your computer without actually buying any. It's a very useful piece of software that can helps a lot when you're on the move and need more working space without having to carry multiple big heavy monitors with you. You can learn more about Spacedesk at http://spacedesk.ph/ and how to download the viewer for other operating systems including your smartphone (if you have one).

If you have any questions, please feel free to leave a comment or even better, join the Discord[bigscreenvr.com]!
See you soon in BigScreen!

[wh1t3c0d3r]

So, in short, the author fixed this little flaw we were using :(
If anyone have ideas, I'm open ;)

[wh1t3c0d3r]

OK. It is possible to make it work with the HTML viewer, but this is probably temporary and requires an Internet connection. The other way I found is rather complicated for most users and is only possible on routers (firewalls actually) that allows it.
It's to use a port forward to redirect TCP and UDP (yes, both) traffic coming on port 28252 on the firewall to the computer's IP address. This won't open the port to external devices if done properly. This basically just bounce back the packets.
This requires that NAT reflection is enabled (should be by default, but on some firewalls [like mine] it's not).
I'm not sure if it's clear...

To make it work, you basically just need to make the connection APPEAR to be coming from the "outside". So, if I can find a built-in way to redirect packets from one IP address to another one WITHOUT assiging a new address to an interface on the same computer (because it's blocked by the client) and without an external device (or VM), it should work....

[wh1t3c0d3r]

Indeed, the new version doesn't seem to be working that way anymore. I'm looking for a way around right now. Thanks for reporting!

[Brunovsky]

Sorry to say that it doesn't worked for me... spacedesk says 'cannot detect server!' if i try connect to primary machine (server) and enter my local ip it say ''invalid host:local IP'' same if i use my computername..

[Robert]

just tested and it works. just got some fps flicker/performance issues, will test further.

[wh1t3c0d3r]

Hi rubjellyonme! I've just tried and it still works for me. Can you please join BigScreen's Discord and contact me directly? It should be easier to find out what's happening that way. http://bigscreenvr.com/discord

[xxxGAM1NGFARTGOD69xxx]

worked once, now spacedesk gives me black screen

[shanks]

Very useful guide, thanks!