V-Ray DMC采样器原理释疑

各采样器比较

自适应细分是一个几乎所有其他“有偏差的非物理渲染器”（注1）都在采用的算法。它是一种相对来说有点老式，但在绝大多数情形下都非常好用的算法。它会算出干净且采样细致的图像结果，在静帧渲染时的表现非常出色，但是与DMC采样器相比，自适应细分往往会在一些本可以采样再少一点的地方过多采样
DMC采样器，那么要在某些同样的地方求出同样质量的反射模糊可能就不用这么多样本，DMC是目前在求取镜头景深和三维运动模糊时最好用（时间短质量高）的光线追踪采样算法

详解“采样”，自适应采样

计算机自己判断出在有必要的时候，才增加对个别像素的采样。这就是自适应采样技术，因为采样的数目是依据图像的复杂程度而适应性变化的。那么在颜色对比比较明显的地方采样数量会增加
自适应细分和DMC采样的共同点是它们都是自适应性的采样算法，但是工作机制不同

细分采样器

细分算法的采样点是处于如图所示的像素顶角上，初始样本采集到信息以后，细分采样器会分析这些信息，然后来决定哪些像素需要更多的采样样本。每一个像素边角上的样本都被拿来比较，如果某个像素的色差大于参数面板中设定的颜色阈值（下图所示），Vray就会进一步细分这个像素，并且在这个像素上采集更多的样本
难以理解，先放着

Apple's One-Dollar-a-Year Man, By Steve Jobs, 2000

(FORTUNE Magazine) – Now that Steve Jobs has showed his hand on Apple's Internet and system software strategies and dropped the "interim" from his title, other questions loom. He's always denied it, but isn't it true that his old company, Next, did wind up taking over Apple? Will there ever be an encore to the 15-year-old Macintosh? Short of that, does Apple have any plans to jump into the "Internet appliance" fray? Will Apple ever build computers for business people again? And what, pray tell, does Steve think of all these young Internet zillionaires? Let's ask. Practically every technology that your old company, Next, possessed when Apple acquired it in 1997 is now being used by Apple in some strategic way. This must seem like sweet vindication. The thing about Next was that we produced something that was truly brilliant for an audience that our heart really wasn't into selling to--namely, the enterprise. I suppose if you were wr...

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巴菲特致股东信-1980年

笔记：会计中对于下属股权公司的记账方式有3种：持股50%以上，全部并入持续20%--50%，则按持股比例并入持股20%以下，则以实际收到的利润返还，计入报表这种会计方式，会导致伯克希尔旗下，不少的企业，未能暴露实际的收益情况对伯克希尔而言，对盈余的认定并非取决于持股比例是100%，50%，20%，5%或是1%，盈余的真正价值在于其将来再投资所能产生的效益我们宁愿将所赚的盈余继续交由不受我们控制的人好好发挥，也不希望转由我们自己来浪费高通货膨胀等于是对投入的资本额外课了一次税翻译： https://xueqiu.com/6217262310/131837878 https://archive.ph/XMX5n 原文： Buffett’s Letters To Berkshire Shareholders 1980 巴菲特致股东的信 1980 年 Operating earnings improved to $41.9 million in 1980 from $36.0 million in 1979, but return on beginning equity capital (with securities valued at cost) fell to 17.8% from 18.6%. We believe the latter yardstick to be the most appropriate measure of single-year managerial economic performance. Informed use of that yardstick, however, requires an understanding of many factors, including accounting policies, historical ca...

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产品爱好者周刊第26期：PRISM, XKeyscore, Trust No One

Products Gitea - Git with a cup of tea https://gitea.io/en-us/ A painless self-hosted Git service. 自建Git服务，避免GitHub隐私侵犯 https://github.com/objective-see/LuLu LuLu is the free macOS firewall 监视Mac的出站流量，且阻断 OverSight https://github.com/objective-see/OverSight OverSight monitors a mac's mic and webcam, alerting the user when the internal mic is activated, or whenever a process accesses the webcam. 监视是否有应用调用Mac的麦克风、摄像头 Mozilla Hubs https://github.com/mozilla/hubs The client-side code for Mozilla Hubs, an online 3D collaboration platform that works for desktop, mobile, and VR platforms. 开源的多人虚拟空间，Mozilla打造，企业级VR诉求数字移民 https://shuziyimin.org 关于内容源、工具的推荐，适合刚接入国际的新人 SimpleLogin https://simplelogin.io/ 匿名邮箱工具，转发用，Michael Bazzell推荐 Telegram 群组、频道、机器人 - 汇总分享 https://congcong0806.github.io/2018/04/24/Telegram/#机器人-bot https://archive.ph/iJMBj 献给那些将来到Telegram的朋友 Design Patrick Wardle https://www.instagram.com/patrickwardle/?hl=en 他的IG，摄影也精彩，审美...

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《Becoming Steve Jobs》Chapter 16 Blind Spots, Grudges, and Sharp Elbows

Steve could be pretty thin-skinned when someone prominent criticized the aesthetics of his products. He took great umbrage that Neil would, as Steve put it, “pop off in public like that without coming to talk to us about his technical concerns first.” From that point on he had rebuffed all of Neil’s attempts to smoke the peace pipe. 有趣 He had blind spots, grating behavioral habits, and a tendency to give in to emotional impulse that persisted his entire life. These characteristics are often used to make the case that Steve was an “asshole” or a “jerk,” or perhaps simply “binary”—that odd adjective often used to convey the sense that he was half asshole/half genius from birth to death. These aren’t useful, interesting, or enlightening descriptions. What’s more illuminating is to take a look at the specific ways in which Steve failed to do an effective job of tempering some of his weaknesses and antisocial traits, and to consider how, when, and why some of them continued to flare up even...

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Steve Jobs: `There's Sanity Returning', 1998

Nobody can doubt the charisma of Steven P. Jobs. The interim CEO of Apple Computer Inc., who returned to the company last July after his ignominious 1985 ouster, has brought back his legendary vision, impatience, and infectious passion for the Macintosh. Jobs spoke to Business Week Correspondent Andy Reinhardt in Apple's stark, fourth-floor boardroom, just after the company rolled out its new software strategy on May 11. Note: This is an extended, online-only version of the Q&A that appears in the May 25, 1998, issue of Business Week. Q: Now that you've introduced the new, bold-looking iMac, are you going to do some radically different products? A: There's a lot of talk about such things -- about handhelds, set-top boxes. A lot of computer companies have been searching for a consumer product. My view is that the personal computer has been the most successful consumer product of the last 10 years. What we have to do, what the industry stopp...

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产品随想 | 周刊第127期：晨光只开一刻钟，但比千年松，并无甚不同

Cherry Studio https://github.com/CherryHQ/cherry-studio Cherry Studio is a desktop client that supports for multiple LLM providers. Support deepseek-r1 Aalto Repository beta https://repo.aalto.fi/ Images, sounds and videos from Aalto University 这个系列，价值极高 Nokia Design Archive https://nokiadesignarchive.aalto.fi/ 芬兰这个国家很了不起对话影石刘靖康：两代未出现划时代的产品，就会沦为平庸的品牌 https://www.geekpark.net/news/308996 还挺喜欢这个创始人的，有一种海盗的内涵从哈佛、明星创业者到酷家乐副总裁，苏奇的传奇 https://app.modaiyun.com/mdy/article/3FO4K4W0M259 WHO关于猫狗咬伤、抓伤的处理建议动物咬伤： https://www.who.int/zh/news-room/fact-sheets/detail/animal-bites 狂犬病： https://www.who.int/zh/news-room/fact-sheets/detail/rabies 关于狂犬病的10个事实： https://www.who.int/zh/news-room/facts-in-pictures/detail/rabies INDIGO 新年直播（2025） https://www.youtube.com/live/ZIgPvSDGAfY 对2024年AI发展的回顾部分特别好 Artab https://github.com/get-artab/artab Get Inspired by the World's Greatest Artworks Every Time You Open a New Tab. Extension Available for Chrome, Edge, and...

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A Sister’s Eulogy for Steve Jobs

I grew up as an only child, with a single mother. Because we were poor and because I knew my father had emigrated from Syria, I imagined he looked like Omar Sharif. I hoped he would be rich and kind and would come into our lives (and our not yet furnished apartment) and help us. Later, after I’d met my father, I tried to believe he’d changed his number and left no forwarding address because he was an idealistic revolutionary, plotting a new world for the Arab people. Even as a feminist, my whole life I’d been waiting for a man to love, who could love me. For decades, I’d thought that man would be my father. When I was 25, I met that man and he was my brother. By then, I lived in New York, where I was trying to write my first novel. I had a job at a small magazine in an office the size of a closet, with three other aspiring writers. When one day a lawyer called me — me, the middle-class girl from California who hassled the boss to buy us health insurance — and said his cl...

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SS机场常用服务器线路微普及

原文link：https://www.duyaoss.com/archives/57/ 为何写这么个帖子？更新时间：2019-11-29 由于机场用户增多，很多新用户压根不懂节点上面的名字代表什么，也不知道什么服务器比较适合自己，不懂什么是原生，等等。所以开一个小帖，稍微介绍一下比较常见的服务器，专业知识有限，所以只是给小白们介绍一下，其实我也很白，各位大佬见笑了。在这里尤其感谢 Sukka 苏卡卡大佬和喵酱指导，以及 Nexitally 佩奇提供的资料介绍，否则我真不知道从哪儿开始动笔。后面地区内容都是佩奇帮忙码出来的。时间有限，慢慢再继续填充和修整本文仅仅是抛砖引玉写一些机场主们告知我的 ISP、IDC 的体验，仅供参考。网络环境每天都在变化，今天飞快的服务器明天有可能龟速，有写的不对或者过时的地方还望大家指正。所以本文也算是一些机场主们把曾经踩过的坑分享给大家吧。（本来是想给小白写服务器介绍的，佩奇大佬写着写着就专业惯性的转到了商家哈哈哈，这是一个悲伤的故事）测速图 Telegram 频道： https://t.me/DuyaoSS 主用链接： DuyaoSS - 毒药机场简介博客常见名词： IPLC: "International Private Leased Circuit"的缩写，即“国际专线”。不过大部分机场通常看到的iplc，都只是阿里的经典网络，跨数据中心内网互通，阿里内网，并不是严格意义的iplc专线；当然也有其他渠道的，或真iplc，不过比较少。阿里云的内网互通底层原理是通过采购多个点对点的iplc专线，来连接各个数据中心，从而把各个数据中心纳入到自己的一套内网里面来。这样做有两个好处，其一是iplc链路上的带宽独享，完全不受公网波动影响，其二是过境的时候不需要经过GFW，确保了数据安全且不受外界各种因素干扰。但是需要注意一下阿里云的iplc也是有带宽上限的，如果过多的人同时挤到同一条专线上，峰值带宽超过专线的上限的话也同样会造成网络不稳定。其他渠道购买到的iplc价格很高，阿里云内网这种性价比超高这种好东西且用且珍惜。 IEPL国际以太网专线（International Ethernet Private Line,简称IEPL)，构建于MSTP设备平台上...

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产品随想 | 周刊第130期：集结信徒，而非官僚

On Dyson, techno-centric design and social consumption https://2earth.github.io/website/20250707.html 如何創造偉大的事物 https://ryolu.notion.site/1610a94b9c108079a95be4362afd4a26 集結信徒，而非官僚 Reflections on OpenAI https://calv.info/openai-reflections 创业架构 Shui https://github.com/rock-zhang/Shui 好好喝水 https://www.ghibli.jp/works/ 吉卜力作品的高清图 From Skeuomorphic to Liquid Glass: Apple's Strategic Bet on the Post-Touch Future https://omc345.substack.com/p/from-skeuomorphic-to-liquid-glass 迄今为止关于苹果Liquid Glass变革的解读，最好的一篇 The Nueva School https://en.wikipedia.org/wiki/The_Nueva_School?useskin=vector 看起来是很酷的一个学校 The Barbican https://arslan.io/2025/05/12/barbican-estate/ 史蒂夫·乔布斯希望你阅读的 9 本书 https://www.douban.com/doulist/147158849/ 《禅者的初心》里有句话：“做任何事，其实都是在展示内心的天性，这是我们存在的唯一理由。” Chuck Feeney was one of the greatest philanthropists ever https://www.gatesnotes.com/Remembering-Chuck-Feeney 慈善家 My new deadline: 20 years to give away virtually all my wealt...

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简要分析Hacking Team 远程控制系统

原文来自乌云，备份地址 0x00 前言 7月5日晚，一家意大利远程控制软件厂商HackingTeam的内部数据被泄露出来，其影响力不亚于斯洛登事件及维基解密事件，绿盟科技威胁响应中心随即启动应急响应工作。 6日，威胁响应中心启动应急分析工作，绿盟TAC产品拦截到Flash 0Day漏洞攻击； 6日夜，相关信息及初步建议，第一时间告知客户关注； 7日，在官网网站发布紧急通告，建议广大用户关注事件进展。分析工作进展进展中； 9日，发布Hacking Team远程控制系统简要分析报告；这是一份快速报告，以便简要分析其中的核心内容，Hacking Team RCS（远程控制系统）。 0x01 泄露：Hacking Team 7月5日晚，一家意大利软件厂商被攻击，其掌握的400GB漏洞（包括0day）数据泄露出来，由此可能引发的动荡，引起了业界一片哗然。数据包中主要包含几个大的部分：远程控制软件源码，也是其核心，暂且称之为 Hacking Team RCS 反查杀分析工具及相关讨论文档 0Day、漏洞及相关入侵工具入侵项目相关信息，包括账户密码、数据及音像资料办公文档、邮件及图片其他 0x02 Hacking Team Hacking Team在意大利米兰注册了一家软件公司，主要向各国政府及法律机构销售入侵及监视功能的软件。其远程控制系统可以监测互联网用户的通讯、解密用户的加密文件及电子邮件，记录Skype及其他VoIP通信，也可以远程激活用户的麦克风及摄像头。其总部在意大利，雇员40多人，并在安纳波利斯和新加坡拥有分支机构，其产品在几十个国家使用。 0x03 分析：远程控制系统大家知道IT运维管理中常常用到远程控制软件，比如Dameware，但Hacking Team RCS相比市面上常见的远程控制软件而言，主要区别如下：系统化管理该软件从入侵到目标信息收集分析，有完整的体系架构，这个架构中有不同的功能模块，彼此之间相互配合，完成入侵、安装、信息搜集、监控、集中管理等功能。收集信息该软件在后台收集并上传目标用户的信息，包括各类数据、图片、影音等入侵工具配合该软件有各种漏洞、利用手段及自动化工具，以便在目标上强制安装Agent 适应能力强桌面OS从Windows到Mac...

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