Sunsetr: Gamma Issue With Multiple Monitors On Wayland

Hey guys! Let's dive into a tricky issue some users are facing with Sunsetr, specifically when using multiple monitors with the Wayland backend. This can be a real headache, especially if you're trying to get that sweet blue light filter working across all your screens. We'll break down the problem, explore potential causes, and discuss possible solutions. So, if you're struggling with Sunsetr and multiple monitors, you're in the right place!

Understanding the Problem

The core issue, as highlighted in a discussion on GitHub (psi4j/sunsetr#33), is that Sunsetr's gamma adjustment, which is responsible for the blue light filtering effect, isn't being applied consistently across all connected monitors when using the Wayland display server protocol. Imagine you've got your laptop screen and an external monitor, but only one of them is getting that warm, eye-friendly tint. Super frustrating, right?

This problem seems to be popping up specifically for users on Wayland. Wayland is the next-gen display server protocol that's gradually replacing the older X11 system on Linux. It's designed to be more modern, secure, and efficient, but like any new technology, it can have its quirks and compatibility issues. One of those quirks, in this case, appears to be how gamma adjustments are handled across multiple outputs. Gamma correction is crucial for applications like Sunsetr, as it's the mechanism by which the color temperature of your display is adjusted to reduce blue light emission, especially during evening hours. This helps in reducing eye strain and improving sleep quality. When gamma isn't applied correctly across all monitors, the user experience is significantly hampered.

To really understand why this is happening, we need to dig a little deeper into how Sunsetr interacts with the display server and how Wayland manages multiple displays. Essentially, Sunsetr needs to communicate with the display server to adjust the gamma settings. This communication might not be working as expected in a multi-monitor Wayland setup. There could be a bug in Sunsetr itself, an issue with the Wayland implementation, or even a combination of both. This complexity makes troubleshooting a bit challenging, but not impossible. Understanding the intricacies of display server protocols and their interactions with applications like Sunsetr is key to finding a robust solution. The inconsistencies observed in gamma application across multiple monitors highlight the need for further investigation into the communication pathways and the specific configurations that trigger this issue.

Potential Causes and Technical Deep Dive

So, what could be causing this issue? Let's put on our detective hats and explore some potential culprits. There are several areas we can investigate, ranging from Sunsetr's internal workings to Wayland's handling of multiple displays. First, we need to consider the specifics of the Wayland backend. Wayland Compositors, like Niri (mentioned in the original discussion), are responsible for managing the display outputs and applying gamma adjustments. Different compositors might implement these functions in slightly different ways. This means that a solution that works for one compositor might not necessarily work for another. It's essential to identify the common patterns and differences in how various Wayland compositors handle gamma to pinpoint the root cause of the problem.

One possibility is that Sunsetr isn't correctly identifying all the connected displays or isn't sending the gamma adjustment commands to each display individually. This could be due to a bug in Sunsetr's multi-monitor support. The application might be designed to work with a single primary display, and the logic for extending these adjustments to secondary displays might be incomplete or flawed. In a multi-monitor setup, each monitor is essentially a separate output, and Sunsetr needs to interact with each output to apply the correct gamma settings. If the application fails to recognize or correctly address these individual outputs, the gamma adjustments will not be applied uniformly across all displays.

Another potential cause lies in the Wayland protocol itself or in the specific implementation within the compositor being used. Wayland is designed with a modular architecture, and different compositors have the flexibility to implement features in their own way. This variability can sometimes lead to inconsistencies in how gamma adjustments are handled. For instance, the compositor might not be correctly propagating gamma changes to all the connected outputs, or it might have its own color management system that is interfering with Sunsetr's adjustments. Debugging this kind of issue requires a deep understanding of the Wayland protocol and the internal workings of the compositor being used.

Furthermore, the graphics drivers play a crucial role in the display pipeline. Issues with the graphics driver could also lead to incorrect gamma application. Outdated or buggy drivers might not be fully compatible with Wayland or might not correctly handle gamma adjustments in multi-monitor setups. Ensuring that the graphics drivers are up to date and compatible with both Wayland and the specific hardware configuration is essential for troubleshooting display-related issues. In addition to these software-related factors, hardware differences between monitors could also contribute to the problem. Different monitors might have different color profiles or gamma characteristics, and these differences could become more apparent when Sunsetr is attempting to apply a uniform gamma adjustment across all displays. Addressing these hardware-related factors might involve calibrating each monitor individually or adjusting the settings within the display itself.

Troubleshooting Steps and Solutions

Okay, enough with the potential causes – let's talk solutions! If you're facing this gamma issue with Sunsetr on Wayland, here's a step-by-step approach you can take to troubleshoot and hopefully fix the problem.

1. Update Everything: This is the golden rule of troubleshooting. Make sure you're running the latest version of Sunsetr, your Wayland compositor (like Niri, Sway, or Hyprland), and your graphics drivers. Outdated software is a common source of bugs, and updates often include fixes for known issues. Graphics drivers, in particular, can have a significant impact on display-related functionality, so keeping them up to date is essential. Check your distribution's package manager for updates and install any available updates for Sunsetr, your compositor, and your graphics drivers. For proprietary drivers, you may need to download the latest version from the manufacturer's website or use a driver management tool provided by your distribution.
2. Check Sunsetr Settings: Dive into Sunsetr's settings and see if there are any options related to multi-monitor support or display selection. It's possible that Sunsetr has a configuration setting that needs to be adjusted for multi-monitor setups. Look for options that allow you to specify which displays should be affected by the gamma adjustment. If there are settings related to display identification or output selection, make sure they are configured correctly to include all connected monitors. Experimenting with these settings may help you identify a specific configuration that resolves the issue. Additionally, check if there are any settings related to the gamma adjustment method itself. Sunsetr might offer different methods for applying gamma, and one method might work better than others on Wayland.
3. Investigate Wayland Compositor Configuration: Your Wayland compositor might have its own settings that affect gamma handling. Check the compositor's documentation for any relevant configuration options. Some compositors may have specific settings for managing gamma across multiple displays or for handling color management in general. These settings could be located in a configuration file or in a graphical settings interface. Refer to the compositor's documentation for detailed information on how to configure these settings. If the compositor has its own color management system, it's possible that this system is interfering with Sunsetr's gamma adjustments. Try disabling or adjusting the compositor's color management settings to see if it resolves the issue.
4. Monitor Environment Variables: Setting environment variables is a powerful way to customize the behavior of applications and the system. Environment variables can influence various aspects of the system, including the way applications interact with the display server. To modify environment variables, you can edit your shell configuration file (e.g., .bashrc or .zshrc) or set them temporarily in the terminal before launching Sunsetr. If specific variables are known to affect gamma handling, setting them appropriately can help resolve compatibility issues. For example, there might be variables that control the default display or the gamma correction method used by the display server. It's essential to research and understand the specific variables that are relevant to Wayland and your compositor before making changes. Incorrectly setting environment variables can lead to unexpected behavior or even prevent applications from launching, so proceed with caution and consult the documentation for your system and compositor.
5. Test with Different Compositors: If possible, try using Sunsetr with a different Wayland compositor to see if the issue persists. This can help you isolate whether the problem is specific to the compositor you're currently using or if it's a more general issue with Sunsetr and Wayland. Each Wayland compositor has its own implementation details, and the way they handle gamma adjustments might vary significantly. By testing with different compositors, you can determine if the issue is related to a particular compositor's implementation or if it's a more fundamental problem. This approach can provide valuable insights into the root cause of the issue and help you narrow down the scope of the troubleshooting efforts. If Sunsetr works correctly with one compositor but not another, it suggests that the problem is likely related to the compositor's specific handling of gamma or multi-monitor configurations.
6. Report the Issue: If you've tried everything and still can't get Sunsetr to work correctly across all your monitors, it's time to report the issue to the Sunsetr developers. Provide as much detail as possible about your setup, including your operating system, Wayland compositor, graphics card, drivers, and Sunsetr version. Also, describe the issue in detail, including what you've already tried to fix it. Reporting the issue helps the developers understand the problem and work on a solution. When reporting the issue, be sure to include any error messages or logs that you've encountered, as this information can be invaluable in diagnosing the problem. Screenshots or videos demonstrating the issue can also be helpful in conveying the problem clearly. Be patient and responsive to any follow-up questions from the developers, as they may need additional information to reproduce the issue and find a fix.

Example Code snippets or commands

Unfortunately, there's no one-size-fits-all code snippet or command that will magically fix this issue, as the solution depends on the underlying cause. However, here are some examples of commands you might use to investigate and troubleshoot:

• Checking connected displays: xrandr --query (if you have XWayland running) or compositor-specific commands (e.g., swaymsg -t get_outputs for Sway)
• Setting gamma manually (for testing): xgamma -gamma 0.8 (again, if XWayland is involved)
• Checking logs: Examine the logs for Sunsetr, your compositor, and the system in general for any error messages or warnings.

Remember to adapt these commands to your specific setup and Wayland compositor.

Staying Patient and Contributing

Dealing with these kinds of compatibility issues can be frustrating, but remember that the open-source community thrives on collaboration. By sharing your experiences, troubleshooting steps, and findings, you're helping not only yourself but also other users and the Sunsetr developers. Be patient, keep experimenting, and don't hesitate to ask for help in the Sunsetr discussions or on other relevant forums. Your contribution, no matter how small, can make a big difference in making Sunsetr a better experience for everyone. By working together, we can overcome these challenges and ensure that Sunsetr works seamlessly across all our multi-monitor Wayland setups!

Conclusion

The Sunsetr gamma issue with multiple monitors on Wayland is a tricky problem, but hopefully, this guide has given you a good understanding of the potential causes and how to troubleshoot it. Remember to update your software, check your settings, and don't be afraid to dive into the compositor's configuration. And most importantly, be patient and contribute to the community! By working together, we can make Sunsetr shine on all our screens. Good luck, guys, and happy blue light filtering!