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## Comment Re:3D programming requirements (Score 1)591

Sigh. Typos in the rotation. Should have been:

Rotation: X = X * cos(theta) - Y * sin(theta); Y = Y * cos(theta) + X * sin(theta);

## Comment Re:3D programming requirements (Score 1)591

No. I am one of the primary authors of what might be fairly described as a Photoshop-class application -- one with far more layer modes and built-in filters than Photoshop, as well as a full-bore built-in ray tracer and texturing facility. It is also considerably smaller and faster than Photoshop in the identical system environment. I am also the author of multiple realtime video and arcade games, etc. I'm telling you flat out that matrices are not required. Period.

Matrices may be the only way you know how to do these kinds of graphics; but they definitely aren't the only way to do it.

Just to take your example: "if you have 3-vectors (i.e. points relative to the origin in 3-space), any global linear transformation is represented by a matrix multiplying each vectors"

The correct way to state this is: "if you have 3-vectors (i.e. points relative to the origin in 3-space), any global linear transformation can be represented by a matrix multiplying each vectors." Here is the non-matrix approach (and of course, there's always polar, which can also be easily handled.) This is for 2D points; 2D vectors and 3D points and vectors are all just a further (and trivial) generalizations of the following:

Translation: X += deltaX; Y += DeltaY
Rotation: X = X * cos(theta) - Y * sin(theta); Y = Y * cos(theta) + Y * sin(theta);
Scaling: X *= Xfactor; Y *= Yfactor

Shadows and reflections can be trivially accomplished with more of the same. Basically: R = 2(V dot N)N - V

"dot" is just the dot product, which again is a trivial combination of the lowest math primitives. ...and so on.

You are confusing the fact that matrices can be used to do something with the idea that matrices are the something.

With algebra, trig, and basic math in hand, the programmer's doors to 2D and 3D graphics are wide open.

## Comment Re:Probably not (Score 1)72

Your phone is always awake, or can be, which is to say, the CPU running, albeit in a lower power state. From there, it takes very little energy to simply record what the mic is picking up. It doesn't need to be translated, and it can be sent, compressed, at widely spaced intervals in terms of battery load. It could be sent while you are otherwise connected. You'd be unlikely to notice a difference in power consumption.

## Comment Re:Probably not (Score 1)72

Funny. Also precisely on target.

When speech recognition gets "decent", as TFS inaccurately states, which is to say, when it's good enough to understand me as well as a human does, then a lot of things will change. For instance, I wouldn't be typing this on a keyboard. I'd be speaking, which is quite a bit faster than typing. Probably never touch my phone other than to slip it into a pocket. Especially after there's a decent, power-efficient wearable display, or an in-eye projection, in front of face hologram, etc.

Right now, what the author calls "decent", I would describe as not even close to acceptable, with a grace note of "better than nothing."

I think it'll be a white yet, based on the crappy stuff available right now.

On the other hand, speech synthesis is actually decent at this point in time. :)

## Comment Re:Programming (Score 1)591

I'm sorry, I tried to read your post, and Culture20's post, with your reasoning in mind, but everything that was written reduced to "words", and then to letters, and then to dots on my display, all the same thing, no meaning remaining at all.

So I think I'll stay with "coding" and "programming" taken to mean making computers do things for us. Yes, "coding" applies to a markup language. "Programming" does not. From TFS: "Olga Khazan writes in The Atlantic that learning to program involves a lot of Googling, logic, and trial-and-error—but almost nothing beyond fourth-grade arithmetic."

Now. Let's say you are ejected from school on the first day of fifth grade. You passed 4th grade with flying colors, though. Now you are sent to a desert island with a computer. Alone. No network. No books. No communications. No reference materials on the computer. Just you, an abundance of tropical fruit and fish, your grass hut and a computer, let's say solar-powered. You are not going to be able to program it until, or unless, you figure out a great deal more than "fourth-grade arithmetic."

Programming. It actually means something more than piddling about with markup language and 4th grade math.

## Comment 3D programming requirements (Score 1)591

Linear algebra (matrices) and trig are essential for doing 3D graphics.

Trig is. Matrices aren't. Translation, rotation, scaling, texturing, light and shadow simulation -- all can be done without matrices. Matrices have nothing inherently linked to 3D about them. They are simply a neat way to concatenate operations and/or factors that can be, but don't have to be, used.

## Comment Re:Turing Test (Score 1)308

Same reason the advertising industry relies heavily on attractive females: it overrides some higher function of the male brain.

"Same reason the advertising industry relies heavily on attractive females: it overrides all higher functions of the male brain in the vast majority of cases."

FTFY.

## Comment Trying to meet someone, how? (Score 1)308

...because in my experience 80-90% of the women on the paid site were working, self-sufficient adults...

So... that's like, what, eight or nine women?

Or are you counting law enforcement trolls, male impostors, and corporate shills, too? That'd probably get you up to 40% or so of these site's supposedly "female" accounts, the rest being bots pretending to be women, which don't count as "working, self-sufficient adults."

I'm truly glad you met someone you found worthwhile, but in the vast majority of situations, these sites are not good hunting grounds for an actual reasonable partner.

The old standbys are still by far the best, assuming one can pull their head out of their phone or laptop or ipad long enough to actually look around them and actually speak to people. Laundromats, grocery stores, libraries, classes of various types, museums, music stores (what few are left.) You know, places where reasonable, normal people tend to go and can be engaged in the creaky old technique of face-to-face, physically-present conversation. Where you can smell each other, sense each others body language, see how the other person moves, how they do at/with eye contact, make physical contact, engage in courting and other courteous behaviors...

I truly think the current crop of young people have gone and shot themselves in the foot with their overwhelmingly present "everything is online all the time" mentality. Not that you can't find someone online, of course you can, but the real world is still a much better place to try. If, of course, you have at least basic social skills and at least a few desirable characteristics. If not, then things haven't changed one whit -- you're screwed, and not in the "OMG I scored" way. Online won't help such a situation either.

As long as we're going to reinvent the wheel again, we might as well try making it round this time. - Mike Dennison

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