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Comment Re:He's right (Score 1) 357

You are free to do that. Some, such as corporate customers or those just concerned about security, may want the original binaries as compiled by the company that is selling them. As snowgirl pointed out, you are not free to take those binaries and redistribute them at will.

I like this. This is the type of open source business model that I think a lot of people have been looking for. We want our software to be open. We also want to feed ourselves and our families.

Comment Re:Server technology? (Score 1) 271

Making a copy of digital information is either lossless or the copy is in error. The making of an analog copy is lossy due to any or all of thermal, electrical, and mechanical noise. The analog copy is also lossy due to bandwidth limits and nonlinearities of the components of the analog system.

Comment Re:Slashvert (Score 1) 536

Once you get an iPod/iPhone/iMac/mac mini "open" it is actually very easy to service the parts. The smaller devices use little ZIF ribbons that make it fairly easy, the computers use interfaces that are also easy to figure out even if you've never serviced your own computer. Had apple not made it hard to open these devices there would be a lot more people buying replacement parts to fix these devices rather than shelling out for new ones. Apple could have easily kept the same form factors and made these devices user serviceable, it just means there are a couple screws on those shiny back plates.

Comment Re:Given two programmers (Score 1) 609

If you're going to do anything in the way of signal processing you will need much more advanced math skills. You're going to need to know calculus, fourier transforms, laplace transforms along with their discrete versions (dft, fft, z). These are extremely useful, powerful mathematical techniques for analyzing data. The mathematics behind them are amazing and elegant. Examples of their use include the enabling of the 'digital' content age through video and audio compression. That's just one example, they can be used to analyze any data stream. It is amazing using DSP to find data in a sea of noise.
First Person Shooters (Games)

Code Review of Doom For the iPhone 161

Developer Fabien Sanglard has written a code review for id Software's iPhone port of Doom. It's an interesting look into how the original 1993 game (which he also reviewed to understand its rendering process) was adapted to a modern platform. "Just like Wolfenstein 3D, Doom was rendering a screenframe pixel per pixel. The only way to do this on iPhone with an acceptable framerate would be to use CoreSurface/CoreSurface.h framework. But it is unfortunately restricted and using it would prevent distribution on the AppStore. The only solution is to use OpenGL, but this comes with a few challenges: Doom was faking 3D with a 2D map. OpenGL needs real 3D vertices. More than 3D vertices, OpenGL needs data to be sent as triangles (among other things because they are easy to rasterize). But Doom sectors were made of arbitrary forms. Doom 1993's perspective was also faked, it was actually closer to an orthogonal projection than a perspective projection. Doom was using VGA palette indexing to perform special effect (red for damage, silver for invulnerable...)."

Comment Re:watts of boom (Score 4, Informative) 209

TDP is thermal design power. It is the number that CPU vendors give to system builders to let them know the max power consumption of the processor so that thermal solutions can be properly designed. If the CPU goes beyond the TDP the system will power off unless there is lots of headroom in the thermal solution.

Having worked on these processors at the circuit level(*) I can tell you that your '100W over TDP' number is rubbish.

If you'd like to know more about what happens when chip vendors fudge on this "invalid metric" search for "nvidia bumpgate". If our chips were running at 100W over spec'd TDP we'd have a lot of very unhappy customers.

* yes, I'm an engineer at AMD and I designed major components on the parts discussed ITFA. I did my time at Intel as well.

Comment Re:OpenGL has/had Killer Apps! (Score 3, Interesting) 515

There's one truly Killer App that's not on there - Mac OS X. The low-level APIs use OpenGL for hardware acceleration on supported GPUs (pretty much any discrete GPU in a late model Mac).

Comment Re:Wow. (Score 1) 143

AMD's chips are on a silicon-on-insulator (SOI) technology, which comes with less parasitic source/drain cap and no junction leakage. Switching less cap means you switch faster. No junction leakage means your part uses less power when it's idle. High-k will be coming soon enough for AMD, the 45nm tech is competing pretty well w/o it at the moment.

AMD uses an exclusive cache architecture, Intel's is inclusive. Exclusive means that a given line exists in only one cache at a given time. Inclusive means that if a line is in one cache, it's in all of them. For an AMD chip add up all the caches on the die to get total cache size. For 45nm quad-core products that's 8.25MB. For an Intel chip take the size of the last level cache, that's your effective total cache. For Nehalem that's 8MB.

You are correct about issuing and higher IPC coming with Bulldozer.

Comment Re:It's a black hole! (Score 1) 234

Sorry, but that's incorrect. Photons do not interact with fields inside atoms, they interact with electrons and protons. That is how lenses, photosynthesis, photodiodes, etc works. Photons are messenger particles of the electromagnetic force. Protons and electrons are the "receivers". Photons do not interact with each other except, as integer spin particles (bosons) they can occupy the same quantum state. This allows for the superposition of two photons to increase, decrease, or cancel out the amplitude of an electromagnetic field at a point in space.

Comment Re:It's a black hole! (Score 1) 234

Electromagnetic fields are made of photons. An incoming photon will be superimposed (interfere) with the photons in an electromagnetic field as it passes through but it's path will remain unchanged. The only way to influence the path of a photon is to bend spacetime, which is the definition of what we call gravity.

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