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New Animated PNG Creation Tools Intend To Bring APNG Into Mainstream Use

Lord_Naikon Re:GIF /does/ support true colors (246 comments)

Wow, a little bit condescending aren't we? Of course I know what an "alpha layer" is, that is why I didn't mention it my post. I merely showed that with sufficient effort good quality GIFs can be made, reducing the need for yet another "not quite video" standard. Speaking of standards, APNG was rejected by PNG. It is only supported by Firefox. So animated GIF is certainly better supported and "more standard" then the proposed alternative.

about a year ago
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New Animated PNG Creation Tools Intend To Bring APNG Into Mainstream Use

Lord_Naikon GIF /does/ support true colors (246 comments)

It's worth noting that GIFs may overlay multiple image blocks with separate color pallets, resulting in true color images.

The problem here is that some browsers (chrome) insert an artificial 0.1s delay between "frames".

Also if you can do this with GIF one has to wonder if APNG has actually any viability other than as a source format.

about a year ago
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MIT Uses Machine Learning Algorithm To Make TCP Twice As Fast

Lord_Naikon Re:Headline epic fails. (250 comments)

Huh? Did you read the same article as I did? As far as I can tell, the article is about a TCP congestion control algorithm, which runs on both endpoints of the connection, and has nothing to do with QoS on intermediate routers. The algorithm generates a set of rules based on three parameters resulting in a set of actions to take like increasing advertised receive window and tx rate control. The result of which is a vastly improved total network throughput (and lower latency) without changing the network itself.

I fail to see the relevance of predictive/adaptive caching. It isn't even mentioned in the article.

about a year ago
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Life After MS-DOS: FreeDOS Keeps On Kicking

Lord_Naikon Re:Dosbox or freedos (255 comments)

Some old games (duck tales comes to mind) just didn't care about the the time and always ran their physics/render loop as fast as possible, with a fixed time step. Later, games (Classic Unreal for instance) started to use the RDTSC instruction that came with the Pentium, which subsequently lead to problems on SMP systems and/or CPUs with power saving features, due to a non-constant tick rate. I suspect Mech Warror 3 also uses it. Microsoft "fixed" that by introducing the QueryPerformanceCounter() API. Funnily enough, because a cheap high frequency time counter is also very valuable to OS developers, the RDTSC instruction now no longer returns the number of clocks but is a constant rate counter and old games work again, especially if the OS takes care to somewhat synchronize the TSC across all CPUs.

It seems timekeeping is still very much in a state of flux, with several timers available to choose from: 8253 timer, ACPI timer, LAPIC timers (per cpu), HPET timers and finally TSCs on each core, each with their own drawbacks.

> UpdatePhysics( elapsedTime );

IMHO the biggest problem with that is that it leads to jitter in the animation because it is impossible to determine in advance how much time you will spend rendering the subsequent frame/when the frame will actually be displayed (unless V-sync is turned off, then it becomes slightly easier). I don't think replays or synchronization between multiple computers are compelling arguments for fixed rate physics simulations, because running your physics simulation in lockstep with the server is basically impossible (and unnecessary IMHO); for replays all that is required is a log of all important events with an associated timestamp. I remember some multiplayer games from the past who did fixed step simulations and they all sucked because they limited the speed to the slowest computer. It is much better to have the server (fast computer) run an accurate simulation and the slow client to run an inaccurate simulation which is corrected frequently by updates from the server.

I'm also not entirely convinced by your examples. In my experience, exploding physics mainly happen if there is an unexpected delay between simulation steps. It looks to me like your simulation isn't properly damping the springs, or the time-step size is exceptionally jittery, but I could be wrong of course.

about a year and a half ago
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Cassandra NoSQL Database 1.2 Released

Lord_Naikon Re:Hmm. (55 comments)

It's not always about the data relationships. Cassandra for example is very easy to scale horizontally (much easier than traditional databases) and can achieve very high throughput. Last time I checked (a year ago) I could get over 50,000 stores/queries per second on a cluster of cheap commodity hardware (4 servers). That result was achieved with full redundancy (n=2). Such a setup is very resilient against failure (provided clients handle failure of individual nodes correctly). Maintaining such a cluster is also a breeze, with the ability to pull servers at will while operations continue to run. You no longer have to deal with brittle master-master/slave setups.

At the time I checked and tested about 10 different "NoSQL" solutions for viability. I had these requirements in mind:
1) Must scale horizontally, no single master dependency and must continue to work when any single node in the cluster fails.
Lots of NoSQL solutions failed this requirement because they had explicit master servers or didn't do redundant data storage.

2) Must perform at least 10,000 reads/writes of tuples per second per node on the bladeservers we had available.
Again lots of NoSQL solutions failed to perform. Some were incredibly slow, with less than a 1000 queries/sec/node.

3) Must have good management tools.
Most NoSQL databases were crap in this department.

4) Must be well supported by open source (Java) libraries.
Most of them were, but a lot of them failed to cope correctly with unreachable/failed cluster nodes.

In the end Apache Cassandra was the only one which fulfilled all my requirements.
Our use cases were persistent caching (as a cache layer behind memcached), and high volume (simple) data storage.

about 2 years ago
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New Releases From FreeBSD and NetBSD

Lord_Naikon Re:FreeBSD 9.1 Is Unix Heaven (149 comments)

Yes, that is exactly the way to enjoy FreeBSD - use it for what it's good at. FreeBSD + nVidia is awesome. State of the art compilers, every port installs its development headers, knowing that _you_ are in complete control of the system instead of the other way around. Outstanding development platform. I love it!

about 2 years ago
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ACM Queue Interviews Robert Watson On Open Source Hardware and Research

Lord_Naikon Re:Hardware support for more sandboxes (37 comments)

Watson wants to be able to change hardware as well as software in his research, instead of only software. He explains that changes to the hardware allow greater performance and/or capability of (for instance) the capsicum framework. Keep in mind that R. Watson is a researcher, not a product developer.

about 2 years ago
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Bethesda: We Can't Make Dawnguard Work On the PS3

Lord_Naikon Re:Consoles are at their limit (371 comments)

The way you program the GPU has drastically changed since the advent of shaders, for both Direct3D and OpenGL. In the end, both APIs are now glorified memory managers (for texture and vertex buffers); all the actual effects and vertex transformations are programmed using shaders. Any other functionality they offer (matrix operations for instance) can be replaced by other libraries. Annoyingly both APIs use a very similar but different shader language. ATI vs nVidia is still a problem though in terms of the stuff you can do with shaders (and the quality of the drivers).
You will find that the most important vendor specific extensions people have been using for years are now in the core library (in particular vertex buffers).

more than 2 years ago
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The Truth About Hiring "Rock Star" Developers

Lord_Naikon Re:Troll Article? (487 comments)

Couldn't agree more. It is always good to speak to someone on the same level about the problems you're trying to solve; especially if they're architecture related with large ramifications if you get it wrong.

more than 2 years ago
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Solid State Quantum Computer Finds 15=3x5 — 48% of the Time

Lord_Naikon Re:Can someone explain... (262 comments)

On the subject of splitting hairs...
1) Every ATM locks you out after a couple of tries.
2) You don't find the first digit. You find all of them at once with 1/(10000-n) probability (where n is the number of known bad codes).
3) Terminator 2 is awesome.

more than 2 years ago
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Your Favorite Technology That Didn't Come To Pass

Lord_Naikon Re:Solar Panels (317 comments)

I don't know where you get your numbers from, but a normal laptop uses about 35W or less 95% of the time (idling).

more than 2 years ago
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Ask Slashdot: What Is the Best Position To Work For Long Hours?

Lord_Naikon Stress is a major factor (262 comments)

In my experience people who complain about back/arm problems are the people who are stressed most. Relaxed people change position often and don't force anything.

more than 2 years ago
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On my summer vacation, I did / will do / am doing:

Lord_Naikon Re:I plan on doing.. (240 comments)

For my vacation I'm working on a "heavy duty" beer-bringing robot. It's basically a moving platform with a beer crate on top. You can "call" it by clapping once. I'm still designing the electronics but it will probably feature 4 microphones, 4 PICs, 1 ARM, 1 accelerometer, 1 gyro, 2x 120 RPM motors (differential steering). I've just finished welding & painting the frame and I am about to mount the motors. Looking forward to the finished product :-)

more than 2 years ago
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Why Valve Wants To Port Games To Linux: Because Windows 8 Is a Catastrophe

Lord_Naikon Re:Gamers move to Linux? (880 comments)

OTOH a lot of users are already invested in to the steam platform. They of course want to be able to access their games on Windows 8 so they will install steam one way or the other, ensuring steam's survival.

more than 2 years ago
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Asus Delivers Speed Boost With USB Attached SCSI Protocol

Lord_Naikon Re:Does SATA fit into the mix anymore? (93 comments)

So, a kernel could have a single SAS driver that supports all SAS, SATA, and USB block devices. This could be a marvelous convergence.

I know FreeBSD does that, using the CAM (Common Access Method) subsystem. Presumably other OSes do something similar.

about 2 years ago
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Australian Sex Party May Sue Google Over Ad Refusal

Lord_Naikon Re:porn party? (183 comments)

Actually, in the Netherlands there used(?) to be a "pedophile" party. Its goals among others were the lowering of the legal age of consent to 12 years. As long as the party itself acts within the boundaries of the law, they are free to promote any political opinion, even if these clash with the current law. This is very important for a healthy democracy.

more than 2 years ago
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The Problem With Metacritic

Lord_Naikon Re:FTA (131 comments)

I too found Oblivion to be boring. Once I set foot outside the starting dungeon I felt lost, without sense of purpose or direction. I liked skyrim a whole lot more due to its faster pacing and sense of urgency. The improved graphic fidelity also helped a lot. Other open world games that worked for me were the new Fallout series. Another example of an interesting single player game is obviously (the golden standard) Baldur's Gate 2, where none of the encounters are scaled and everything is unique.

more than 2 years ago
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Why Ultra-Efficient 4,000 mph Vacuum-Tube Trains Aren't Being Built

Lord_Naikon Re:kinetic energy (625 comments)

Since their seems to be much confusion about this point I'll try to explain it in more detail.

The article is both right and wrong.
If the train needs to actively push itself along the track (using powered wheels) we have to deal with the following formula (for the purposes of this though experiment I've set the mass of the train to 1kg):

W = F * s

Where W is the work/energy (in Joule), F is the force (Newton) and s the distance travelled (meters).
Suppose the train is already going 100m/s and needs to accelerate to 200m/s. Using its wheels it exerts a force of 10N on the train. So it will take 10 seconds to accelerate to 200m/s (V = a * t, a = F/m). In that time it will have travelled 150m/s * 10sec = 1500m. In ideal conditions it would have taken the train 10N * 1500m = 15kJ/kg. Accelerating from 1000m/s to 1100m/s would result in an energy expenditure of 1050m/s * 10sec * 10N = 105kJ/kg, much more energy.

On the other hand, if the train is powered by a rocket, it doesn't have to push itself along the track but instead it pushes itself by pushing rocket fuel at high speed out of the back.

Why is this not more efficient? Because you need to accelerate the rocket fuel as well (and lots of it). In a way the rocket fuel does what the earth it self does for a normal train (a diesel train even uses combustion like a rocket to push itself forward). Because the normal train doesn't have to carry the earth with it it is more efficient. However, there is a point (very high speed) where a rocket train becomes more efficient, because the speed difference between the exhaust gases and the train are not dependent on the trains "absolute" (relative to the earth) speed.

more than 2 years ago
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What's To Love About C?

Lord_Naikon Re:Good habits (793 comments)

Can you give a concrete example where the GC fails to detect a cyclic reference? IIRC Java's garbage collector eventually traces through all stacks looking for live objects; any objects not referenced on any stack, directly or indirectly through other live objects, are then deleted. Regardless of any cyclic references between dead objects, the outcome should be the same.

more than 2 years ago

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