kernel 编译补遗

上回说到我的kernel能够启动了，不过还是有些问题。

一个是不断出modprobe: fatal: 说找不到.../modules.dep之类，而且一出就好几屏，上网搜了一下，也有人遇到这问题，不过好像他们都是不能启动，估计跟我情况不一样。后来经高人指点，原来我的kernel不用initrd, 于是make-kpkg时不要--initrd就好了（一开始没出initrd我还以为出bug了）

另外是声卡的问题，我查了下，并不是没认出声卡，而是多了dummy设备和virtual midi设备，我没查到如何配置alsa默认声卡，于是呼把这两个选项去了。

最后是说dma没打开，不知道为什么当时漏掉了，不过它还真是体贴，提醒了一下，要不然我以后慢的都不知道怎么回事。

最后基本就都正常了，跟原来比，启动是多了一点点错误信息，但是似乎不影响使用。

Comments

Determine Perspective Lines With Off-page Vanishing Point

In perspective drawing, a vanishing point represents a group of parallel lines, in other words, a direction. For any point on the paper, if we want a line towards the same direction (in the 3d space), we simply draw a line through it and the vanishing point. But sometimes the vanishing point is too far away, such that it is outside the paper/canvas. In this example, we have a point P and two perspective lines L1 and L2. The vanishing point VP is naturally the intersection of L1 and L2. The task is to draw a line through P and VP, without having VP on the paper. I am aware of a few traditional solutions: 1. Use extra pieces of paper such that we can extend L1 and L2 until we see VP. 2. Draw everything in a smaller scale, such that we can see both P and VP on the paper. Draw the line and scale everything back. 3. Draw a perspective grid using the Brewer Method. #1 and #2 might be quite practical. #3 may not guarantee a solution, unless we can measure distances/p...

[转] UTF-8 and Unicode FAQ for Unix/Linux

这几天,这个东西把我搞得很头疼而且这篇文章好像太大了,blogger自己的发布系统不能发只好用mail了 //原文 http://www.cl.cam.ac.uk/~mgk25/unicode.html UTF-8 and Unicode FAQ for Unix/Linux by Markus Kuhn This text is a very comprehensive one-stop information resource on how you can use Unicode/UTF-8 on POSIX systems (Linux, Unix). You will find here both introductory information for every user, as well as detailed references for the experienced developer. Unicode has started to replace ASCII, ISO 8859 and EUC at all levels. It enables users to handle not only practically any script and language used on this planet, it also supports a comprehensive set of mathematical and technical symbols to simplify scientific information exchange. With the UTF-8 encoding, Unicode can be used in a convenient and backwards compatible way in environments that were designed entirely around ASCII, like Unix. UTF-8 is the way in which Unicode is used under Unix, Linux, and similar systems. It is now time to make sure that you are well familiar ...

Moving Items Along Bezier Curves with CSS Animation (Part 2: Time Warp)

This is a follow-up of my earlier article. I realized that there is another way of achieving the same effect. This article has lots of nice examples and explanations, the basic idea is to make very simple @keyframe rules, usually just a linear movement, then use timing function to distort the time, such that the motion path becomes the desired curve. I'd like to call it the "time warp" hack. Demo See the Pen Interactive cubic Bezier curve + CSS animation by Lu Wang ( @coolwanglu ) on CodePen . How does it work? Recall that a cubic Bezier curve is defined by this formula : \[B(t) = (1-t)^3P_0+3(1-t)^2tP_1+3(1-t)t^2P_2+t^3P_3,\ 0 \le t \le 1.\] In the 2D case, \(B(t)\) has two coordinates, \(x(t)\) and \(y(t)\). Define \(x_i\) to the be x coordinate of \(P_i\), then we have: \[x(t) = (1-t)^3x_0+3(1-t)^2tx_1+3(1-t)t^2x_2+t^3x_3,\ 0 \le t \le 1.\] So, for our animated element, we want to make sure that the x coordiante (i.e. the "left" CSS property) is \(...

WangLu's Notes

Search This Blog