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An Unbelievable Demo

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Re: An Unbelievable Demo

#201

Post by BlueTemplar »

wruza wrote: post #163
maccard wrote: post #125

Earlier quoted context omitted.

I can't say, I'm not sure what compression we used on the last two games I worked on, sorry!

It is very unlikely that it was a “continuous” compression anyway. Continuous archives disallow random file access property, and games require exactly that for assets. You can’t decompress few gb on average to fetch a sprite of a cat. The reason games (and software in general) do full downloads instead of binary patches is purely overdefensive and/or stupid. Store software could just check checksums after a patch and…

Well, whether they use full versions or diffs is also going to depend on how much they care about bandwidth.

Re: An Unbelievable Demo

#202

Post by j-pb »

mothsonasloth wrote: post #193

Is the "D" prefix in things like DTrace a Sun standard/convention? What does it mean, for example in the JVM arguments start with "D" as well. Any history to this?

TL;DR: DTrace uses a minimalistic C dialect called D to write it's probes, hence the name.

In order to trace arbitrary code, it has to inject these into the code site that you want inspected.

If you could just inject arbitrary C, you'd get the issue of potentially adding probes which change the behaviour of your code under test to a degree where new bugs/behaviours are introduced or old bugs/behaviours are masked.

DTrace solves this by using a C subset which helps you avoid such unwitting changes, by not including loops or other operations which could change the memory or timing behaviour of the existing system.

Re: An Unbelievable Demo

#203

Post by rwmj »

jasonkester wrote: post #197

It makes me sad that the way a developer is expected to react when they discover that the Valuable Thing that they gave away for free is being sold by a Big Company for Big Money is to try to ensure that the Valuable Things they give away in the future remain free. I'd much prefer to see the people who build Valuable Things show more interest in capturing some of that value. There's this overwhelming narrative revolv…

If that's what you took from the article, then you got completely the wrong end of the stick. The problem was the removal of the author's attribution and illegal relicensing. He says himself he was glad when Apple later included his tools in macOS with correct attribution and licensing.

Re: An Unbelievable Demo

#204

Post by PeterisP »

mewse wrote: post #173
maccard wrote: post #112

Earlier quoted context omitted.

One of the reasons games do this is the data is compressed, so a "patch" might be indistinguishable from a real update. Also, as a dev, you have no idea what version your users are updating _from_. You either need to generate some number of patches for every version you could be updating from, and figure out if you should just download the whole thing again in any of those cases anyway.

We usually don’t compress the data on disk; decompression would make loading and file access slower. Instead, we just pack the uncompressed files together (frequently using normal zip in a no-compression mode) so that we can avoid needing to ask the OS to open and close files for us or examining the contents of a directory, both of which can be kind of startlingly slow (by video game standards) on some common OSes. I…

IIRC in a bunch of scenarios compression makes loading and file access faster, as you're I/O limited and it's quicker to read less data and decompress. You do need to choose simple/quick/not-that-much-compressing compression algorithms for that.

Re: An Unbelievable Demo

#206

Post by jasonkester »

rwmj wrote: post #203
jasonkester wrote: post #197

It makes me sad that the way a developer is expected to react when they discover that the Valuable Thing that they gave away for free is being sold by a Big Company for Big Money is to try to ensure that the Valuable Things they give away in the future remain free. I'd much prefer to see the people who build Valuable Things show more interest in capturing some of that value. There's this overwhelming narrative revolv…

If that's what you took from the article, then you got completely the wrong end of the stick. The problem was the removal of the author's attribution and illegal relicensing. He says himself he was glad when Apple later included his tools in macOS with correct attribution and licensing.

Exactly. That was the problem that he saw.

The problem he should have noticed was that the Sun was selling the code he wrote for hundreds of thousands of dollars and not passing any of that on to him.

Step one shouldn't have been to worry about putting his header comment back in place and getting them the latest version of his code to sell to their customers. It should have been negotiating a redistribution license for his code if they wanted to continue selling it.

Re: An Unbelievable Demo

#207

Post by kuroguro »

A colleague of mine was attending a local tech conference just before Covid hit. I believe it was aimed at newcomers and various companies tried to show off exciting tech that interns/new coders could potentially work on.

She couldn't believe what she saw. A major govt. backed logging company (which does do a lot of dev work themselves) were showing off one of our projects as theirs! We were using depth cameras to estimate the volume of wood loaded on a truck as it drives trough a gate. They even used screenshots that I had made!

Now, they were involved in the project. But they were basically clients of our client. They provided us with a place to test the system as their trucks ran trough. They didn't own the software let alone did any work on it. Why they would present it as something interns could potentially work on is beyond me.

People are weird.

Re: An Unbelievable Demo

#208

Post by tialaramex »

mewse wrote: post #173
maccard wrote: post #112

Earlier quoted context omitted.

One of the reasons games do this is the data is compressed, so a "patch" might be indistinguishable from a real update. Also, as a dev, you have no idea what version your users are updating _from_. You either need to generate some number of patches for every version you could be updating from, and figure out if you should just download the whole thing again in any of those cases anyway.

We usually don’t compress the data on disk; decompression would make loading and file access slower. Instead, we just pack the uncompressed files together (frequently using normal zip in a no-compression mode) so that we can avoid needing to ask the OS to open and close files for us or examining the contents of a directory, both of which can be kind of startlingly slow (by video game standards) on some common OSes. I…

> We usually don’t compress the data on disk; decompression would make loading and file access slower.

Did you actually benchmark this? It probably makes sense in your head, but on any vaguely modern hardware it's very unlikely to actually be true because of how exponential the memory hierarchy is.

Re: An Unbelievable Demo

#209

Post by BlueTemplar »

jasonkester wrote: post #197

It makes me sad that the way a developer is expected to react when they discover that the Valuable Thing that they gave away for free is being sold by a Big Company for Big Money is to try to ensure that the Valuable Things they give away in the future remain free. I'd much prefer to see the people who build Valuable Things show more interest in capturing some of that value. There's this overwhelming narrative revolv…

IMHO the problem is the term "free software" :

https://www.gnu.org/philosophy/selling.en.html

Re: An Unbelievable Demo

#210

Post by lostlogin »

not2b wrote: post #60
BrandoElFollito wrote: post #37

Earlier quoted context omitted.

See, at least you realize you are a tiny country with a small population and the ego adapted to that. I am French and we are a country with a great past - but not looking ahead. We still assume that we radiate across the world and that our voice counts. It does not, and this has to be clear. There are countries that can influence events, but this is not ours. A typical example is how angry we were after the recent pi…

But there are consequences; Belarus is now cut off from air travel except with Russia. Flights are avoiding their airspace. They are a pariah.

Have you seen the coverage of the interview of Roman Protasevich? The visible injuries on his wrist and his recently adjusted attitude are alarming. https://www.bbc.com/news/world-europe-57353413
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