SimHub Ambilight Plugins: Drama in the Sim Racing Community – CAAL vs. DNR

After SimHub added support for ambient lighting (Ambilight) a few years ago, things went quiet around this feature for quite some time. That changed with the release of Bruno Silva’s Cockpit Auto Ambient Light plugin a few months ago. More and more content creators began showcasing the plugin to their communities in their videos. Shortly thereafter, DNR released a feature that was perceived by parts of the community as very similar, subsequently sparking a discussion.

Context: What is an Ambilight plugin?

An Ambilight plugin for SimHub expands the field of view with dynamic ambient lighting (e.g., from Philips Hue or Govee) and makes the experience on the racetrack in the simulator significantly more immersive. However, using it is usually a bit of a hassle, as the screen detection zones must be manually repositioned for each vehicle cockpit so that the light illuminates the surroundings and not, for example, the dark car roof in the game. These plugins solve exactly this problem by fully automating this adjustment process. Using SimHub data, they automatically detect the car currently being driven and dynamically move the detection zones for the Ambilight to the appropriate positions. Additionally, there are various other features that make life significantly easier.

The Cockpit Auto Ambient Light plugin was developed by Bruno Silva and made available to the community free of charge. DNR’s Ambient Lights feature, on the other hand, was released as part of the Daniel Newman Racing plugin for SimHub. A monthly membership costing up to €12.89 per month is required to use it.

Drama in the sim racing community and accusations

Just a few days after Dan Suzuki and other content creators posted videos about the Cockpit Auto Ambient Light plugin, Daniel Newman Racing made its first announcement regarding its own development. What stands out most is the speed at which DNR’s features, first introduced on June 3 (“BIIIIIIG Ambient Lighting RELEASE …”), evolved: Initially, there was a basic version with many bugs and issues. Revisions were then made at a very rapid pace, so that, according to Bruno Silva and the report he presented, there were increasingly more similarities to CAAL’s feature list. This quickly led to accusations from the developer of the Cockpit Auto Ambient Light plugin. He stated on various public Discord servers that, in his opinion, parts of his project had been copied. The accusations culminated in a roughly ten-page report created by Bruno Silva or with his involvement (“DNR-vs-CAAL-v1.12.0-technical-evidence-report-FINAL.pdf”), in which he compared the various plugins and analyzed their contents.

The report analyzes the technical development of the DNR Ambient Lights plugin (versions 4.4.1 through 5.1.7) in comparison to the Cockpit Auto Ambient Light (CAAL) plugin, version 1.12.0. The report describes a technical evolution that gradually converges with the methods used by CAAL.

• DNR 4.4.1 (Initial State): This version did not yet include any algorithms for automatic cockpit masking or similar subsystems. This was the state of the system before similarities to CAAL emerged.
• DNR 5.1.0 (First Similarities): This version introduced an automatic workflow with a cockpit mask and 8 output zones for the first time. Technically, however, this was still a simple method that merely analyzed pixel movements.
• DNR 5.1.2 to 5.1.5 (Further Development of the Simple Method): These versions built upon the early approach and mainly introduced refinements to settings such as sensitivity, color adjustments, and smoothing. However, the basic, simple functionality remained unchanged.
• DNR 5.1.6 (The Major Turning Point): This is where the greatest technical convergence with CAAL took place. DNR switched to a more complex detection of stable cockpit regions (instead of pure motion analysis) and integrated adaptive brightness adjustments. This new architecture was significantly more similar to the approach of CAAL v1.12.0 than the previous DNR versions.
• DNR 5.1.7 (Further Detail Convergence): Focused scanning areas for the lower cockpit and a fallback function for very dark scenes were added. This represents a further convergence toward the robust low-light capabilities and zone design that CAAL was already utilizing.

Conclusion of the report: According to Bruno Silva’s report, he concludes that later versions of DNR converge significantly with CAAL in terms of methods and architecture. However, the report also emphasizes that there are still significant technical differences (e.g., 8 zones in DNR vs. 13 zones in CAAL, or differences in signal processing). For this reason, the report states that while it demonstrates a strong similarity in conceptual approach, it does not prove direct, verbatim copying of the source code.

Daniel Newman’s response on Discord didn’t take long to arrive. In a statement that could certainly be read with a touch of irony, he acknowledged Bruno Silva’s “excellent work” but vehemently denied the allegations of plagiarism. Newman explicitly emphasized that the DNR plugin was a completely independent development. According to his statement, the new system is the culmination of continuous development of their own ambient light profiles, which have been on the market for two years. The sudden release of the feature was merely held back long enough to bundle it appropriately with the major V5.0 update of their own software. Unfortunately, Daniel Newman Racing did not respond to our request for a statement on the current situation by the time this article was published. Should this change in the future, we will of course publish the statement here and give DNR the opportunity to comment on the events in detail once again.

Technical Background

SimHub is based on Microsoft’s .NET Framework. When someone writes a plugin for SimHub, they typically use the C# programming language and Visual Studio. Once the developer has finished writing the code, they click “Compile” (Build) in their development environment (e.g., Visual Studio). This converts the human-readable C# code into a .dll file (Dynamic Link Library). This file is essentially a finished component that SimHub automatically loads during startup and integrates into its own software. The way C# is converted into a DLL differs significantly from older languages like C or C++.

• Traditional languages (e.g., C++): When these are compiled, the code is translated into pure machine code (ones and zeros) intended directly for the processor (CPU). Reversing this process (reverse engineering) is extremely difficult, and the result is virtually unreadable to humans.
• .NET languages (such as C#): When you compile C#, the code is not translated into direct machine code, but into an intermediate language called CIL (Common Intermediate Language). Only when SimHub is running does the computer translate this intermediate language into actual machine code in the background.

CIL preserves almost all of the “metadata” from the original code. This means that the structure of the classes, the names of the methods, the mathematical formulas, and the logical flow within the DLL remain unencrypted. Because this CIL intermediate language is structured in this way, there are free standard tools designed specifically to decompile these files. Although developers can protect their C# code through so-called obfuscation, hobbyist programmers in free community projects like CAAL usually skip this inconvenient step. As a result, the source code was practically an open book, so that the file could theoretically have been decompiled without issue, and the algorithm could have been copied as one’s own work with slightly modified variables. Technically, this would be possible in principle. Whether this actually occurred in the present case has not been proven.

Cockpit Auto Ambient Light Plugin no longer available

The consequences of this situation so far are as follows: The developer of the Cockpit Auto Ambient Light plugin has taken the free, public version offline. According to his own statements, his work was used without permission in the paid DNR plugin. He criticized the fact that his unpaid work is now being commercially exploited by others in a subscription model costing around six pounds per month. To protect his development work while still making the tool accessible to the sim racing community, he plans to bring the plugin back under a fair, one-time payment model. In his Project Availability Notice, Bruno Silva wrote the following:

Project Availability Notice

Cockpit Auto Ambient Light has been removed from free public access for the time being.

This project was originally released as a free plugin for the sim racing community. It took many hours of development, testing, debugging, and real-world validation to make it work reliably across different games, cars, lighting setups, and Philips Hue configurations.

After the project gained visibility, including after Dan Suzuki’s video, I found that work from this project had been used without my permission in the Daniel Newman Racing plugin, also known as the DNR Plugin. That plugin is distributed as part of a paid subscription model, currently requiring users to pay around £6 per month.

I do not believe it is fair for me to spend a large amount of personal time building, testing, improving, and supporting this plugin for free, only for others to use that work commercially in their own paid product.

Because of that, I have decided to remove the public free release while I consider the best path forward.

I am currently considering bringing Cockpit Auto Ambient Light back under a fair one-time paid model instead of a monthly subscription. My goal is still to keep the plugin accessible to sim racers, but in a way that respects the time, effort, and originality behind the work.

Thank you to everyone who supported the project, tested it, reported issues, gave feedback, and used it in good faith. I genuinely appreciate the community around this plugin.

More information will be shared when a final decision is made.

For more information you can contact me by Email: bruno.1978@gmail.com or reach me on discord brunosilva1978.

Bruno Silva – GitHub (https://github.com/BrunoSilva1978PT/Cockpit-Auto-Ambient-Light-public#project-availability-notice)

Community Feedback

Currently, the feedback from the community is largely consistent. Many users are upset about the allegations. There is also widespread disappointment that the plugin will likely no longer be available to the community for free in the future. What are your thoughts on this? Feel free to share them in the comments, but please keep the discussion civil.

Disclaimer: This article is an editorial summary of publicly available information, documents, and statements from the sim racing community. The allegations made against Daniel Newman Racing (DNR) and the quoted passages reflect the opinions, analyses, and claims of their respective authors (e.g., Bruno Silva, author of the technical report; community members). The editorial team reports on this as a neutral observer and expressly does not endorse these claims and allegations. At the time of publication, despite our inquiry, we had not received an official statement from DNR; this may, of course, be submitted at any time. This article does not, of course, provide a legal assessment of the facts. Whether the allegations made are actually true or relevant under copyright law is a matter of dispute among the parties involved and is not evaluated by the editorial team.