squigs

squigs t1_j6lv93k wrote

Reply to ELI5: Why do computers need GPUs (integrated or external)? What information is the CPU sending to the GPU that it can't just send to a display? by WeirdGamerAidan

They don't need a GPU. Until the 1990s, computers didn't have one at all, unless you count a fairly simple device that reads from a chunk of RAM and interprets it as video data a GPU. Early 3D games like Quake were perfectly fine on these systems, and did all the work on the CPU.

What the CPU sends is a lot of textures, and a bunch of triangles, plus information on how to apply the textures to the triangles.

The CPU could do this but the GPU is a lot faster at certain tasks. Drawing triangles being one such task. Twisting the textures around being another.

Early GPUs just did the texturing. That's the most CPU intensive task.

3

squigs t1_j6c9r2c wrote

Reply to comment by The_camperdave in ELI5: Why do imaginary numbers even need to exist? by Tharsis101

This is where my answer is a bit messy. Imaginary numbers can be thought of that way, but using them for 2d space is an application.

We do have quaternions. This gives us 3 imaginary numbers, we call i, j and k, where squaring any of them gives -1, and ij = k, jk = i and ki =j. Weirdly, we lose commutivity here. ij = k, but ji = -k. Reversing the order gives a negative result.

2

squigs t1_j6bqx9o wrote

Reply to ELi5 : If you can access a website, why cant you steal the source code and make a 1:1 copy of it? by 13lettersinhere

Nothing technical. Just like you can scan and OCR a book, you can copy the code for a website.

But that's copyright violation, which is illegal.

In practice it will rarely do you a lot of good. Sure, there are some static websites, but most are interactice in some way, and usually rely on server side stuff.

0

squigs t1_j6ai3sm wrote

Reply to ELI5: Why do imaginary numbers even need to exist? by Tharsis101

People always fixate on the "square root of -1" thing, but that's not what imaginary numbers are for.

Essentially, numbers give us forward. Negative Numbers give us backwards, and imaginary numbers give us "sideways"

Imaginary numbers give us numbers in 2 dimensions. We don't just look at imaginary numbers on their own, but as a pair. We have a "real" part and an "imaginary" part. Something like 3+4i .

Now, we can convert real numbers to imaginary numbers by multiplying by i. We're basically rotating them. What happens if I rotate something twice? We end up reversing it.

Another way of saying we rotate twice is we multiply by i twice. i x i. Or i². We get -1. Rotate again (multiply by i again), and we get i³ = -i. Rotate again and we're back to where we started. i⁴ = 1.

Like I said earlier, there's an imaginary part and a real part. So 3 + 4i. Rotate by multiplying by i we get 3i + 4 i² = 3i - 4.

26

squigs t1_iy9to82 wrote

Reply to comment by blatantninja in TIL During the 20th century TV series that reached 100 episodes were generally preferred for syndication, since that meant stations could run 20 weeks of programming without repeating a story. In recent years that number has fallen to 88 episodes. by UndyingCorn

Syndication isn't as big a deal any more. Streaming platforms don't care at all since their shows are never going to be broadcast.

1

squigs t1_iy3u6o8 wrote

Reply to comment by unlikemike123 in eli5 How is computer memory deleted? by unlikemike123

Yup. Data recovery firms rely on this.

There are actually some fairly simply tools for most filesystems that will find deleted files.

It's the same with RAM. I think modern systems are more secure, but in the past, hackers were able to break into systems by allocating a large chunk of RAM and seeing if anything that looks like a password was there.

2

squigs t1_iy2rfcy wrote

Reply to comment by IronicBread in TIL In 1930, to make way for a new building, the Indiana Bell Building, weighing 11,000 tons, was moved 16 meters and rotated 90°. The work took a month to finish and did not disrupt the building's essential services, nor its gas, water, and electricity supply. No one inside felt the building move. by LPercepts

>but seeing as it was a telephone exchange building

That makes it even more incredible! Surely there are hundreds of connections into the building rather than just the usual gas, electricity, water.

I wonder if "no interruption" is completely literal, or whether they did need to switch some of these off for a few minutes to connect to a different pipe/cable.

2

squigs t1_irhwnby wrote

Reply to TIL Boeing B17 pilots often accidentally raised the undercarriage after landing, destroying the propellors and damaging the underbelly, due to the undercarriage lever and the flap lever looking the same. by Lkwzriqwea

This is something that often frustrates me in design. People are prone to mistakes (or even downright stupidity at times) but too many people think that this means that we need to fix the person, rather than design around this.

5