Researchers at Linköping University, Sweden, have developed a new method for producing perovskite LEDs that are significantly cheaper and more environmentally friendly than current alternatives. By replacing expensive and toxic elements like lead and gold with more abundant and benign materials like copper and silver, and by utilizing a simpler solution-based fabrication process at room temperature, they've dramatically lowered the cost and environmental impact of production. This breakthrough paves the way for wider adoption of perovskite LEDs in various applications, offering a sustainable and affordable lighting solution for the future.
Reverse engineering of Shenmue's source code revealed that the sun's position in the game is calculated using a simplified formula that doesn't account for axial tilt or the equation of time. This results in the sun rising and setting slightly earlier than it should in the game's real-world counterpart of Yokosuka, Japan, across all in-game dates. While noticeable, this discrepancy doesn't significantly impact gameplay and may have been a deliberate simplification for performance reasons on the Dreamcast. The author speculates whether it qualifies as a "bug" given its likely intentional nature and minimal effect on the overall experience.
Hacker News users discuss whether the perceived sun position error in Shenmue is actually a bug or a deliberate design choice. Some commenters suggest it's a performance optimization, avoiding complex calculations for marginally improved visuals. Others argue it's simply a bug, pointing to inconsistencies with the in-game clock and world design. Several discuss the challenges of reverse engineering older games, particularly with limited documentation, and the difficulty of definitively labeling something a bug without access to the original source code and developer intentions. The discussion also touches on the nostalgic appeal of Shenmue and the dedication of its fan community in dissecting the game's intricacies.
The Graphics Codex is a comprehensive, free online resource for learning about computer graphics. It covers a broad range of topics, from fundamental concepts like color and light to advanced rendering techniques like ray tracing and path tracing. Emphasizing a practical, math-heavy approach, the Codex provides detailed explanations, interactive diagrams, and code examples to facilitate a deep understanding of the underlying principles. It's designed to be accessible to students and professionals alike, offering a structured learning path from beginner to expert levels. The resource continues to evolve and expand, aiming to become a definitive and up-to-date guide to the field of computer graphics.
Hacker News users largely praised the Graphics Codex, calling it a "fantastic resource" and a "great intro to graphics". Many appreciated its practical, hands-on approach and clear explanations of fundamental concepts, contrasting it favorably with overly theoretical or outdated textbooks. Several commenters highlighted the value of its accompanying code examples and the author's focus on modern graphics techniques. Some discussion revolved around the choice of GLSL over other shading languages, with some preferring a more platform-agnostic approach, but acknowledging the educational benefits of GLSL's explicit nature. The overall sentiment was highly positive, with many expressing excitement about using the resource themselves or recommending it to others.
To minimize eye strain while working from home, prioritize natural light by positioning your desk near a window and supplementing with soft, indirect artificial light. Avoid harsh overhead lighting and glare on your screen. Match your screen's brightness to your surroundings and consider using a bias light to reduce the contrast between your screen and the background. Warm-toned lighting is generally preferred for relaxation, while cooler tones can promote focus during work hours. Regular breaks, the 20-20-20 rule (looking at something 20 feet away for 20 seconds every 20 minutes), and proper screen placement are also crucial for eye health.
Hacker News users generally agreed with the author's points about the importance of proper lighting for reducing eye strain while working from home. Several commenters shared their own setups and experiences, with some advocating for bias lighting behind monitors and others emphasizing the benefits of natural light. A few users mentioned specific products they found helpful, such as inexpensive LED strips and smart bulbs. Some debated the merits of different color temperatures, with warmer tones generally preferred for relaxation and cooler tones for focus. There was also discussion around the potential downsides of excessive blue light exposure and the importance of positioning lights to avoid glare on screens. A compelling point raised by one commenter was the need to consider the direction of natural light and adjust artificial lighting accordingly to avoid conflicting light sources.
Summary of Comments ( 111 )
https://news.ycombinator.com/item?id=43384697
HN commenters discuss the potential of perovskite LEDs, acknowledging their promise while remaining cautious about real-world applications. Several express skepticism about the claimed "cheapness" and "sustainability," pointing out the current limitations of perovskite stability and lifespan, particularly in comparison to established LED technologies. The lack of detailed information about production costs and environmental impact in the linked article fuels this skepticism. Some raise concerns about the toxicity of lead used in perovskites, questioning the "environmentally friendly" label. Others highlight the need for further research and development before perovskite LEDs can become a viable alternative, while also acknowledging the exciting possibilities if these challenges can be overcome. A few commenters offer additional resources and insights into the current state of perovskite research.
The Hacker News post titled "Next generation LEDs are cheap and sustainable" linking to a Swedish article about perovskite LEDs, generated a moderate discussion with several interesting points raised in the comments section.
Several commenters focused on the challenges associated with perovskite LEDs, particularly their stability issues. One commenter highlighted the inherent instability of perovskites in the presence of moisture and oxygen, emphasizing the need for robust encapsulation to ensure longevity. Another commenter echoed this concern, pointing out that while perovskites offer advantages in terms of cost and efficiency, their vulnerability to environmental factors remains a significant hurdle for commercial viability. This commenter specifically mentioned the problem of ion migration within the perovskite material leading to degradation.
The discussion also touched upon the potential applications of perovskite LEDs. One commenter suggested that their low cost and tunable color properties make them ideal candidates for displays, particularly large-area displays and potentially even flexible displays. Another comment explored the possibility of utilizing perovskite LEDs in lighting applications, particularly where high color rendering is desirable.
A couple of commenters expressed a cautious optimism regarding the technology. They acknowledged the promising aspects of perovskite LEDs but emphasized the importance of further research and development to address the stability concerns. One of these comments pointed out that while laboratory demonstrations are impressive, translating this success to mass production with consistent performance and lifespan remains a key challenge.
Finally, one commenter questioned the "cheap" claim in the title, arguing that while the materials themselves might be inexpensive, the manufacturing processes, especially those required for effective encapsulation to combat degradation, could add significant cost. This commenter suggested a more nuanced headline would be more appropriate.
In summary, the comments section reflected a measured response to the news of advancements in perovskite LEDs, acknowledging the potential while maintaining a realistic perspective on the challenges that still need to be overcome. The discussion revolved primarily around the stability issues, potential applications, and the overall cost-effectiveness of the technology.