How-To: Virtual Mirror on External Display

These days, external dashboards come in the form of displays of all shapes and sizes, including an increasing number of ultra-wide screens, whether as a VoCore screen or a standard HDMI display. With a few simple tricks, you can create a virtual mirror that significantly enhances the rig’s look and is also practical.

Hardware – HDMI or VoCore

Generally speaking, when it comes to displays, you have the choice between VoCore screens, which are controlled via SimHub, and generic HDMI screens, which are recognized as regular monitors in Windows. SimHub is required to operate the VoCore screens, unless you want to use them as generic monitors in a rather complicated workaround. The biggest advantage of HDMI screens is their typically much higher refresh rate. VoCore displays only truly offer 60 Hz under ideal conditions (when only small sections are being updated), which is not the case when used as a virtual mirror. With HDMI screens, there are models that require both a USB power supply and an HDMI cable, thus needing a free port on the graphics card, as well as models that are powered and receive the signal via a single USB-C cable.

With VoCore screens, you have the choice of housing them yourself in a 3D-printed case as a DIY project or opting for ready-made solutions, most of which include additional LEDs, starting at around €250. HDMI screens are typically shipped in a case, so only a mount is needed.

Hier findet ihr einen exemplarischen Vergleich zwischen einem 12.3HDMI-Display und einem 7.8 Zoll VoCore-Display:

Software – Various options

To mirror the virtual rearview mirror onto the screen (pun intended), there’s a little trick you can use: You take the virtual rearview mirror already available in the simulation and then project the image onto the real screen, either at a 1:1 ratio or stretched. This comes with some limitations, such as the maximum refresh rate and the often low resolution of the virtual mirror. Nevertheless, this gives you a very exciting and practical gadget with relatively little effort. The respective simulation must be run in windowed mode.

SimHub

In SimHub, you can use Dash Studio to define an area to be used for mirroring the virtual in-game mirror. If you then create a suitable dashboard using the screen capture function, you can access that function here and use the mirrored image. The biggest advantage here is clearly the ability to display additional information directly on the mirror. One drawback is the fairly high CPU load caused by SimHub, which is due to the program’s now very extensive scope. Depending on your CPU, you can expect an additional 3 to 5 percent CPU usage. This isn’t a major issue, but it can still be a deciding factor in certain cases.

OBS

When using an HDMI screen, you can use OBS in addition to SimHub to display the video feed on the secondary monitor using the Open Scene Projector feature. Plug-ins also allow you to enable upscaling. However, one drawback here is that the program runs continuously in the background, which can be quite resource-intensive.

SPC Rearview Mirror

Our very own SPC Rearview Mirror software is specifically designed for use in sim racing and for operation with HDMI screens. Here, you can create various profiles, for example, for each game or even for each car (which is handy if you want to mirror the in-car displays instead of using the virtual mirror). Additionally, profiles can be created and various options selected. Thanks to real-time filters for brightness, contrast, gamma, and sharpness, you have full control over the display. The tool saves individual profiles per car. This ensures that the exact selected screen sections, window positions, and scaling modes (Stretch to Fit or aspect ratio) are automatically restored at every startup.

Technically, the software is based on the Windows GDI+ API. It copies the selected screen section directly into a dedicated memory buffer without any detours and scales it using hardware-accelerated bicubic interpolation. Due to its lean architecture without external libraries, the typical CPU load is less than 1% and RAM usage is less than 50 MB. The result is a very powerful, virtually latency-free mirroring with high image sharpness and minimal resource consumption.

• USE AT YOUR OWN RISK: This software is provided “as is” without warranty of any kind. As it is a Beta version, bugs and crashes are to be expected.
• LIMITATION OF LIABILITY: In no event shall the developer be liable for any damages (including, but not limited to, loss of data, hardware issues, or iRacing account issues) arising out of the use or inability to use this software.
• NO REDISTRIBUTION: This software is intended for your personal use only. You are strictly prohibited from distributing, sharing, uploading, or transferring this software to third parties in any form.