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If I'm reading http://fly.srk.fer.hr/GDM/articles/vgamodex/vgamx1.html correctly, then this isn't quite true.

Each byte of each plane apparently represents four pixels, with two bits of each byte going into each pixel. So four planes gives you 256 colours (8 bits per pixel.)

Which is kinda ugly, but no more, I guess, than a lot of 1980s computer graphics technologies.

Unfortunately it also adds to the reasons why just because Carmack worked on a planar version of Doom for the PC doesn't mean his decision to ignore the Amiga was entirely inexplicable. Leaving aside the market share, and the fact I assume to get this to run at any speed, it would have to have been done in assembler (which would be different for the PC and Amiga), code that manipulates double-bit planes is going to be slightly different to that that manipulates single bit planes, and will probably be around twice as fast.

If the Amiga had a chunky mode, I suspect it would have been a no-brainer to port Doom. It would have worked on more models, and only the interactions with the API would have had to be recoded. Oh well.

Replying to my own post - found current working links:- http://old.tel.fer.hr/imunes/ is the project homepage. This link - ftp://borg.uu3.net/pub/archive/imunes/pdf/zec-mikuc-04.pdf - talks about the network stack magic they use.

Indeed -- what he said.

At university (a sub-university entity called "faculty"), in our "Communication Networks" class as well as "Network Programming" class, we used in-house developed IMUNES. Link appears to be dead at the moment, probably because of maintenance being done in the building. I'll try to summarize, though, and you can try using Google's cache.

I'm not sure if it's open source, but I believe it is free. It's a FreeBSD mini-distro that uses an X11 piece of software to allow you to graphically construct the network, and deploy mini-virtual-machines (segments of some sort) with a single click. It allows simulation of routing, of various network speeds, of packet drops, etc. You can easily see the traffic by starting Wireshark on a node (a router, a PC, whatever). You can easily log into each of these nodes.

We received IMUNES as a VMware disk image, and it worked pretty well. We received instructions on how to link individual virtualized IMUNES machines, but I can't remember how to do it right now.

Book is available online here (and a few other places/formats, try google):

http://fly.cc.fer.hr/~unreal/theredbook/

This is an older version, but still a very good grounding in the basics of interactive 3d graphics.

Yes. http://geri.cc.fer.hr/~ivoras/web2/papers/osbench. html

Does VMware's license forbid its use for comparison purposes?

The blanket license does, though we've made exceptions when researchers ask nicely. See, for example, Marko Zec's OASIS workshop paper from ASPLOS XI, which includes benchmark comparisons against a reasonably recent version of VMware Workstation (that show Workstation in a pretty unfavorable light, I might add). I can only speculate as to why the Xen folks don't get treated as well as Marko did; I don't even know for a fact whether they've asked.

Regardless, it's quite possible they asked and we turned them down, in which case, our bad. I'm not really objecting to the substance of the Xen comparisons; if Workstation 3 is all they can compare to, fine. What I object to is the tone with which the Xen guys usually make this comparison. They strive to leave the impression that they've clobbered the best the industry has to offer, when they're really beating up a straw man. No sane customer would use workstation 3 for the uses the Xen folks are measuring.

The reference manual is not what you should be interested in for learning. The specs are available online and can be downloaded easily. For learning you need to get the official OpenGL Programming Guide a.k.a. the Red Book.

Infact some editions of teh red book are even available online in electronic format for example here:

http://fly.cc.fer.hr/~unreal/theredbook/

Not true. The Redbook (OpenGL Programming Guide) uses GLU or GLUT for input, so it is operating system independent. It also happens to be one of the best books for learning OpenGL.

There is a free (quasi-legal) copy of an old version located online. I'd recommend getting the newest version, 4, because it is updated for OpenGL 1.4.

Here are some free online books for ya.

http://fly.cc.fer.hr/~unreal/theredbook/

http://www.cs.man.ac.uk/applhax/OpenGL/

the Red Book is a good guide to everything OpenGl

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Stupid /. Moderators killed my Karma

Ivan's benchmarking document is complete.

I love to use OpenBSD, for lots of reasons. I would love top performance as a bonus, but I use OpenBSD for where I like it to fit.

I'm getting into Gentoo now, so I'm happy there too.

I don't understand why people get so upset over what performs the best. The BSD's and Linux have benefited from each other and in the end we all get to choose what fits our needs the best.

Linux 2.6 excellent performance will probably benefit the BSD's in some way, even if just urging the BSD developers on and in the future no doubt the opposite will be true.

NetBSD made great improvements due to Felix's benchmark.

Within a patched kernel, every process, socket and network interface belongs to a unique virtual image. Each virtual image provides entirely independent:

* set of network interfaces and userland processes;
* interface addresses and routing tables;
* TCP, UDP, raw protocol control blocks (PCBs);
* network traffic counters / statistics;
* set of net.inet tunable sysctl variables (well, most of them actually);
* ipfw and dummynet instance;
* kernel message buffer instance;
* system load and CPU usage accounting;
* proportional share CPU scheduling

Here ya go.

"PGP normally compresses the plaintext before encrypting it. It's too late to compress it after it has been encrypted; encrypted data is incompressible. Data compression saves modem transmission time and disk space and more importantly strengthens cryptographic security. Most cryptanalysis techniques exploit redundancies found in the plaintext to crack the cipher. Data compression reduces this redundancy in the plaintext, thereby greatly enhancing resistance to cryptanalysis..."
PGP User's Guide, Volume 2

I for one have long since encrypted Zip files with PGP when I needed that security

PGP zips files before encrypting them. At least older versions did. See this page

Can't you configure applications to run both in chroot and jail to more fully contain them?

http://aurora.zemris.fer.hr/filesystems/

I just downloaded an incredible find on the net, The GNU C Programming Tutorial. It's well written and completely free. It just goes to prove that there are many people out there who use the net in the spirit it was intended to be used, they just aren't in your face like the porn and spam. I think if you were to compare the amount of sleaze to the amount of beneficial documents on the net, the good stuff would far outweigh the bad.

It's actually a 2-dimensional DCT (discrete cosine transform), some quantization applied inequally (the low-frequency components are better represented; this is the lossy part), and then entropy-coded (Huffman or arithmetic, aka zip-like lossless compression) in a cool zig-zag fashion. Here's a quick, decent summary.

No, PNG does not use LZ77 compression. ... It does not use [Dynamic] Ziv-Lempel-Welch compression.

If you read the description of LZ77 (as distinct from LZW), it sounds an awful lot like the ZIP-Deflate algorithm. I'll assume that Huffman is beyond patent vulnerability as well.

Another page draws the distinction: "A very popular data compression technique is Lempel-Ziv compression. This is used with general purpose file compression programs on computers. Its basic principle is that, as a file is read, the part of the file that has already been processed is used as a dictionary of sequences of bytes likely to occur in that file. When a repeated sequence of bytes is long enough, a pointer back to the earlier part of the file is shorter than repeating the bytes. While the original concept of this kind of file compression is not patented, patents cover Lempel-Ziv-Welch compression, and many other variants which are more practical or efficient than the original form."

They're already heading that way; the Register had an article describing some work being done to do general raycasting in hardware. I guess it's heading towards turning graphics cards into boards full of many highly parallel mini-CPUs, since vertex and/or pixel shading are rather parallelizable in comparison to other things the main CPU might be doing. Of course, OpenGL is already a sufficiently versatile system that one can implement Conway's Life using the stencil buffer, so for a sufficiently large buffer, you could implement a Turing machine; I don't know how much (if any) acceleration you'd get out of the hardware, though.

Along your point, there's actually a technique that uses the self similarity of images to help you compress themselves. For example, you might have seen the "Sierpinsky Triangle." You can generate this image with a few very simple recursive move/resize/draw operations.

Fractal compression uses this technique on abstract images. It aims to find a set of operations (sometimes very large) to generate any given input picture. It's very cool, and you can get more information (including example pictures) at this page.

The "state of the art" of fractal compression beats JPEG compression at some compression ratios, but looses at others. It's also interesting that a fractally-compressed image has no implicit size (ie: 640x460), so it enlarges MUCH better than simple image enlargement.

Excellent point - a brief google search found this page, a summary of the performance of ext2, ext3, jfs, xfs, vfat, and reiserfs.

Here's the red book. I didn't have any luck with the SuperBible though. Post a link if you find it.

Best bet is to get the "Red Book" - the OpenGL programming guide. This is a great book, especially if you're new to graphics concepts. (Although, if you want a good graphics book, Computer Graphics Principles and Practice by Floey, Van Dam et al. is still the best text IMHO).

The Red Book is available online here

Some good tutorials are here .

For general information, plus a lot of good links, www.opengl.org is the place to look.

Gingko

That would be more difficult than it sounds, IMHO. Have a look at the data compression reference center's page on the differences between LZ78 and LZW.

You might end up coding another LZWx algorithm, and the whole family of algorithms (the method) is patented (free for non-commercial use tho).
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Grand Reverence Zan Zu, AB, DD, KSC

It can't handle cookies or SSL either. (well, cookies can done with a hack , but it's a pain. it'd be much nicer if you could just point it at your netscape cookies file)
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It can't handle cookies or SSL either. (well, cookies can done with a hack , but it's a pain. it'd be much nicer if you could just point it at your netscape cookies file)
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