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Comment x/2^n == x>>n (for unsigned integers) (Score 1) 615

Back in the deep mists of time, every programmer worth their salt knew that division was an expensive operation. If they were lucky, the numbers they would have to divide by would be a power of two, and doing so requires a single shift instead of a divide. Back in the day, compilers did not automatically substitute division by a power of two with a shift, and if you were reading sourcecode, you could tell that the programmer knew their stuff if they wrote "x>>1" instead of "x/2".

Then along came optimizing compilers, that were smart enough to know what you were trying to do, and for unsigned integers they would automatically substitute the divide with a shift. Soon after, people stopped writing a shift and just wrote a divide instead, trusting the compiler to do so and in the process, making the code easier to read.

A newer generation of programmers came along, and noticed nothing 'unoptimized' about division by constant powers of two, so they just took it for granted, and were completely unaware of this trick. However, one consequence of this is if picking an arbitrary number to divide by, if they don't choose a power of two, the compiler can no longer do the abovementioned optimization. It used to be the case that arbitrary choices of numbers were powers of two, but not anymore. In fact, if books that had the potential to be turned into video-games were written bearing in mind this optimization, we may see some top-level title-changes. For example, instead if calling it 50 Shades of Grey, E.L. James should have called it Sixty Four Shades of Grey, and if someone tried to compile it, they'd end up with a somewhat faster game.

Also, if we take for granted the compiler will do this for integer division, we may forget that when dividing signed numbers, we may get the compiler producing code like this

(x>0 ? x>>1 : x/2 )

Comment IIS Server resume bug (Score 5, Interesting) 166

Apparently, there's a bug in Microsoft's IIS server that causes corruption when attempting to resume large downloads. FileZilla does not take this into account, and as a result, the download is corrupted. Clearly, this is Microsoft's fault, but the situation is that there are many buggy IIS servers out there, and Filezilla, by not having a workaround for this (other FTP clients do have a workaround), ends up corrupting the download. After looking at this ticket, it shows that the developer clearly does not live in the real world.

Personally, this issue hasn't affected me, but the exchange I linked to tells me a lot about the attitude of the developer. I only even discovered this issue when reading about FileZilla.

So is this fork going to address this issue?

Comment Re:What if they trained it to see Christ (Score 1) 75

Then eBay will be full of charlatans preying on gullible religious people. If they enhance the Jesus-like properties of a burnt spot on a piece of toast, at least when they deliver the toast and the customer is not satisfied, they will still be able to point out similarities between the burnt spot and a more Jesus-like blob as shown in the photo.

Comment Re:Reverse- engineering psychedelics (Score 1) 75

I think this comment on another article is of relevance here.

One possible way of establishing frames of reference (eg. trying to explain the taste of an orange to someone who's never tasted a citrus fruit) is to figure out how to manually stimulate neurons (this does not necessarily involve brain-implants - maybe this can be done purely by meditation or something) and finding out which ones to stimulate for oranges and generic citrus fruit. Then, we could develop vocabulary that can be used to generalise combinations of simulated neurons, and from there, build a platform to intellectually venture deep into the realm of the psychedelic.

I mentioned in the parent-post that an atomic unit of a psychedelic experience might be a surreal juxtaposition. Maybe it's actually trying out something completely new for the first time (eg. a citrus fruit), or even something slightly new (eg. an Orange if you've already had another Citrus fruit), but this may just create a new memory rather than attempt to shift the train of thought outside of standard thought-patterns, so it will just be chalked up as a new experience rather than a psychedelic experience.

Comment Reverse- engineering psychedelics (Score 1) 75

I've never taken any psychedelics myself (so I guess you could call me a psychedelic layperson), but have read several experiences from people who have. One of the things my brain tends to do during it's 'down-time' is to try and interpret these experiences (from the point of view of someone who's not had any first-hand psychedelic experiences) and using my knowledge of neural networks and other geeky things, to try and figure out what is really going on, and hopefully in the process, to figure out the nature of conciousness. I expect this is something I'm almost certainly not going to achieve by myself and it may take several generations until a purely intellectual link is found between the experiences of a deep trip and the realm of scientific and philosophic explanation. Basically, this is attempting to solve the problem by approaching it from the other end. People like Terence McKenna try their best to bring back what they experienced on their trips, but are limited by the lack of established concepts related to what they saw - hence they don't have the tools to properly communicate these things. Because of this, their interpretations tend to focus more on the spiritual side of things than the intellectual side. What people on this side of the 'psychedelic divide' are doing is to try and construct the prerequisite concepts required to properly interpret the ramblings of Terence McKenna

After reading the comments to this Slashdot article and comments posted on the linked articles, some people say it's the closest to a trip they've ever experienced on a purely visual level. Because the article attempts to make sense of what is going on, this could be an important step in developing means of communicating the content of the psychedelic realm. We could also see implications at the other end and figure out exactly what the brain does when tripping - a gold-mine of information for understanding how the brain works.

One thing I've often wondered: what is an antomic unit of a psychedelic experience? My current theory is that any surreal juxtaposition that can break the mind out of the boundaries imposed by the Sapir–Whorf hypothesis could end up displacing the mind in an unknown state, and possibly even create a feedback-loop trying to make sense of it. Perhaps when tripping, the mind is automatically bombarded by so many of these experiences that they may end up gaining insight into the Ultimate Secret of the Universe. Perhaps this is what people who are 'trying to find God' are trying to find. So we could say that God is hiding behind a certain yet-to-be-entertained juxtaposition.

Can someone who's actually had a trip please confirm if I'm on to something, or if I'm just talking out my arse?

Comment Implications for the demoscene (Score 2) 75

Does anyone know if these images can be created in real-time? If so, demo-coders will pounce on the algorithm and have an absolute field-day! Demos will never quite be the same again. Another idea could be an easter-egg for a video-game where if the player has just ended a very intense gaming-session, the visuals of the frontend (even if only the background) could have this algorithm applied to them just to see if the player notices anything out of the ordinary (after a particularly intense session, this will be harder to spot immediately).

I know that training a neural network can take a very long time, but using it to recognise images can be done very quickly. If a standard CPU or GPU cannot do this in realtime, would the more dedicated demo-coders start creating their own FGASs / ASICs that are designed just for this task, and bringing their creations along to demoparties?

Comment How close? (Score 1) 75

I'm curious. Do the visuals just look different or do these psychedelics affect you at a much deeper level (eg. affect the thoughts and not just the visual perceptions)? Have you tried taking a small dose just to see what a 'low-intensity trip' is like? Can you use these photos and the knowledge of the article as a stepping-stone to describe what you do see when you are tripping?

Submission + - Turning neural networks upside down produces psychedelic visuals (blogspot.co.uk)

cjellibebi writes: Neural networks that were designed to recognise images, when run backwards, turn out of being capable of enhancing existing images to resemble the images they were meant to try and recognise. The results are pretty trippy. This blog-post explains the research in great detail. There are pictures, and even a video. The Guardian has a digested article for the less tech-savvy.

Comment Is there an extension that...? (Score 1) 353

...when you visit a clickbait site such as Cracked.com, blocks all the "you may also be interested in" stuff so that you just see what you came to see and don't get distracted into visiting millions of other "10 signs you are a serial procrastinator, number 5 will turn your underwear into a war-zone" links?

So far, after Googling, I have only been able to find "Anti-Upworthy" which de-sensationalises the language of clickbait headlines, but ideally, I'd like to block the display of "you may also be interested in" stuff. And no, using a .hosts file to block the offending site is not an answer because I don't get to see the original article I came to see.

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