Porting Virtual Paradise to the 3DS (part 3)

Also see part 1 and part 2 in this series.

Finally it renders something! This took me quite a while to get working. Apparently the 3DS expects some vectors in WZYX ordering… The wrong ordering caused the projection and view matrix to be incorrect and the result was a blank screen.

However, on a real 3DS it looks like this:

In the emulator I could get quite a bit more working. I added the ability to load 3D models. It doesn’t download from the object path yet so I copied a pre-filled cache folder to the emulator’s virtual SD card as a test:

There it is, VP with 3D models loading on the 3DS emulator 🙂 Of course it is still missing textures, lighting and probably more.

Unfortunately I’m not sure how to fix it so it runs on a real 3DS. It doesn’t just have distorted rendering, with the model loading it hangs a few seconds after starting. Unless I get it working, this will be the last part in the series.

Porting Virtual Paradise to the 3DS (part 2)

In part 1 I was able to build most of VP’s code for the Nintendo 3DS target using the homebrew SDK, but only a small part of it was running: just enough to make it log in.

At the end of the previous article I mentioned that other parts of the code need a functioning renderer. Actually, it just needs to have a renderer that pretends to be functioning. For situations like this VP has a fake renderer. It doesn’t render anything, it just tell the rest of the code that it did and that everything is fine. Let’s use that and see what happens when running it in a 3DS emulator.

It enters the world! You can tell from the screenshot above that the user count for testworld went from 2 to 3. And on the PC the avatar can be seen as well:

Unfortunately, when I tried this on the real 3DS it just crashed. After some online searching I found out that it is possible to enable a remote debugger on the (softmodded) 3DS through the Rosalina menu, which can be accessed by pressing L + Down + Select. I enabled the debugger attached to it using GDB:

(gdb) target remote
Remote debugging using
0x00100000 in _start ()
(gdb) c
[New Thread 216]
[New Thread 219]

Thread 1 received signal SIGSEGV, Segmentation fault.
0x00320328 in strlen ()
(gdb) bt
#0  0x00320328 in strlen ()
#1  0x001bd75c in ObjectPath::getCachePath[abi:cxx11]() ()
... more stack frames

Something appears to be going wrong when trying to find where to put cache files. It’s running the code path that is also used on Linux systems. This code path uses getenv("HOME") to find the home directory and because the 3DS most likely doesn’t have this it returns a null pointer. Adding some 3DS-specific code to determine the cache location fixed this.

There were also some easier to fix issues before it would work. Here it is running on a real 3DS:

After this I started working on a renderer implementation for the 3DS. I managed to make it clear the screen with a color, but it’s not rendering anything yet.

Porting Virtual Paradise to the 3DS (part 1)

Since I made my old 3DS capable of running homebrew software yesterday, I decided it would be an fun project to try porting VP to the 3DS. Considering I only have an old 3DS instead of the “New 3DS” it’s probably not going to be very fast 😅

This port is just an experiment and it might not even be released. I’ve done similar things before, such as a port to the Wii and a port to DOS. Those ports were very incomplete and were never released.

For building the software I’m using the devkitARM toolchain from devkitPro. It turns out that quite a few of VP’s dependencies such as Bullet Physics, zlib, and mbedtls are already available as packages from the devkitPro pacman repository. Not having to build them myself will save some time.

After a few hours of cleaning up the causes of build errors, adding stubs in various places and implementing some system specific functions for the new platform, I have at least the network functionality working:

It logs in and shows the world list, but it doesn’t enter a world yet. While the networking code for entering a world would probably work, other parts of VP expect to have a functioning renderer available. So it will take some more effort to get that working.

Virtual Paradise 0.4.1-alpha.11


  • Lock command (activate and bump triggers only)
  • Fog support in Direct3D 11 renderer
  • Use a forward clustered shading approach for all objects:
    • Support more than 32 lights for transparent objects
    • Get rid of rendering differences between 0.3.x and 0.4.1 alpha versions that were introduced with the deferred shading approach
    • Multisample anti-alias is supported again


  • Fix incorrect Y coordinate in teleport dialog (value was offset by 0.175)
  • Fix exp2 fog mode for OpenGL 1.x renderer (exp was used instead of exp2)
  • Fix names and chat above avatars not visible
  • Fix web command and web overlay not working

Known Issues

  • New lighting approach only available in Direct3D 11 mode
  • UPDATE October 12, 2019: In some cases all objects might render completely black. This is due to a bug in the new fog code. To work around it, enter a world with fog enabled (e.g. VP-Build or test4), then go back to the world you intended to visit.

If you find any other issues, please let me know!


Download for 64-bit Windows
Download for 32-bit Windows

Virtual Paradise 0.4.1-alpha.10


  • Determine active lights for each light cluster using a compute shader, which is much faster with many lights (Direct3D Feature Level 11_0 required)
  • Use a fixed width font used for action fields in object properties
  • Show application name and version when right clicking on users in user list


  • Fix select recent objects (debug menu)
  • Fix too large radius used for light culling (causes more unnecessary lighting calculations to be done, reducing performance)
  • Fix incorrect light culling for nearest light cluster

Known Issues

  • Multi-sample anti-alias needs to be disabled or VP won’t function properly in Direct3D 11 mode
  • New lighting approach only available in Direct3D 11 mode
  • Names above avatars don’t appear
  • Web commands and overlays don’t work
  • Objects with transparent surfaces are still limited to a maximum of 32 active lights for the whole scene


Download for 64-bit Windows

Virtual Paradise 0.4.1-alpha.9


This version does lighting using a ‘clustered shading’ approach. Behavior and performance might be different compared to the previous version.

Starting with this version lights will also have a finite range of 3x the radius= specified in the light command. An object with the following command:

create light color=red radius=20

Will result in a light with the first 20m having the same intensity as in previous versions, but reduce its intensity linearly over the next 40m beyond that. This is added on top of the existing intensity curve, instead of replacing it.


  • Fix specular maps on opaque objects in Direct3D 11 mode
  • Fix sound volume settings not being applied to new sounds (streaming sources like MP3, Ogg Vorbis and Opus only, WAV was unaffected)

Known issues

  • Multi-sample anti-alias needs to be disabled or VP won’t function properly in Direct3D 11 mode
  • New lighting approach only available in Direct3D 11 mode
  • Names above avatars don’t appear
  • Web commands and overlays don’t work
  • Some scenes with many lights may be slower, even on very capable graphics hardware, because the light clusters are calculated on the CPU
  • Objects with transparent surfaces are still limited to a maximum of 32 active lights for the whole scene


Download for 64-bit Windows


I would appreciate any feedback on this test version. Please comment below this post to share your thoughts.

Virtual Paradise 0.4.1-alpha.8

Here’s a new test version of VP ? Download link at the end of this post.

What’s new?

  • Fix non-Direct3D 11 renderers
  • Fix incorrect lighting in OpenGL with shaders mode (spot light falloff was not being applied to specular)
  • Improved network handling
  • Fixed crashes during reconnect
  • Fix crashes when maximum number of active sounds is reached (see jump point doorbell hell)
  • Fix typo in settings dialog
  • Dutch translations updated


Download for 64-bit Windows

Virtual Paradise Bot SDK Bindings for Node.js

The new bot SDK bindings were published on npm yesterday! Bot developers can use this to write VP bots running in Node.js. Because it is using a WebAssembly build of VPSDK compiled with Emscripten it should be easily portable to all platforms supported by Node.js.

Here’s a code example for a bot that shows chat, shows avatar names and replies to messages starting with an underscore:

Some basic events (connection, avatars, chat) and methods (chat, query, teleport) are supported but the bindings are still incomplete. Code contributions, bug reports and feature requests are welcome. These can be done through the GitHub repository for this project.

Vulkan Renderer Progress: Lights

I started working on a Vulkan renderer for Virtual Paradise back in 2016. Halfway through 2017 it could render most static models without any materials or lighting. Until recently I didn’t really put a lot of effort into actually getting it to work. Over the last few weeks I’ve been working on it some more and have actually made some progress! ?

Materials, world light and positional lights are working now:

Lighting working with Vulkan renderer

And this is how it is supposed to look:

The same scene using the Direct3D 11 renderer

So, there is still some work to do! A few things that are missing: textures, spot lights, sky rendering, anti-aliasing, normal mapping, particle systems, 2D elements like avatar name tags, shader based skeletal animation, selection bounding boxes, and probably more.

I’m still getting used to how things work compared to APIs like OpenGL or Direct3D. It’s definitely a lot more difficult to get started (so I took two years to do so ?, although I rarely even looked at it during this time). To take better advantage of this API and use multiple threads for rendering, the main (non-Vulkan-specific) code will also need to be changed, but I think I will focus on functionality first.

This blog is back!?

After an 8 year break, there is a post on this old blog again! The blog was offline for a few years as well, but it is back now.

There was never much to read on this blog, but I hope to change that. I intend to post here every now and then about releases of Virtual Paradise, development progress and perhaps other things too.