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TDM after D3 Source code release


Shadowhide

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Lawyers are still skittish about the patent issue around "Carmack's reverse", so I am going to write some new code for the doom3 release.

 

http://twitter.com/#!/ID_AA_Carmack/status/136614459887202305

 

...with any luck, it'll be a better shadow method too :)

 

I wouldn't worry about the team digging into the Source right away.

 

It would be wise to sit back awhile and see what the rest of the Open Source community comes up with (before committing to some changes that might be hard to back out-of if some new improvement comes along.)

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Well that's dedication, to go & *rewrite* code to be able to release it.

Hope it's still compatible with the vanilla engine. Surely it'd have to be...

What do you see when you turn out the light? I can't tell you but I know that it's mine.

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The sad thing is that someone was able to patent "Carmarcs Reverse", and then the patent is actually still valid. (In the US only, of course. In Europe it is not possible to patent an algorithmn.)

"The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." -- George Bernard Shaw (1856 - 1950)

 

"Remember: If the game lets you do it, it's not cheating." -- Xarax

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Bingo...

 

I knew this would happen.

 

Hey John, we really appreciate this. Thanks for re-writing the affected code and not just throwing your hands up and saying "forget it, I have better things to do".

 

I was beginning to wonder what was the hold up... At least now we know.

Edited by lost_soul

--- War does not decide who is right, war decides who is left.

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And here I thought "Carmack's Reverse" was a euphemism for having inadvertently reverse engineered someone else's code that got in. It's really something he wrote that got patented by a third party. That's unfortunate. (PS, Code has always been a mess for IP law, and having different jurisdictions treat it differently just makes it messier. Happy I don't have to mess with it.)

What do you see when you turn out the light? I can't tell you but I know that it's mine.

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Over at Doom3world the discussion has turned to "the value of patents".

 

The argument is that they encourage new innovation by insuring the research investments of companies.

 

Why not instead use taxes and have Governments perform research?

 

Why does all the benefit from research have to be from for-profit institutions?

 

Why cant we just reward companies that contribute to our collective knowledge rather than let them milk patents and to become monopolies?

 

Many questions that are not being explored over there ... <_<

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This is what the C4 engine developer said when asked about the creative patent.

 

First, the Creative patent is invalid because the depth-fail stencil technique was publicly described by Nvidia before Creative filed for a patent (prior art). There are thousands of games out there that use depth-fail stencil shadows, and Creative knows it can't go after them.

 

The main difference is that the Creative patent explicitly covers a two-pass algorithm in which all the front faces of a shadow volume are rendered separately from all the back faces of a shadow volume, and C4 uses a different method by which all the faces of a shadow volume are rendered in a single pass with arbitrary mixing of front and back faces. The introduction of new hardware capabilities (two-sided stencil operations) makes this possible, and such hardware did not exist at the time the Creative patent was filed. There are also some minor differences in the way that the stencil buffer is updated in C4 compared to the patent claims. In general, it's a different algorithm, but of course, none of this matters because the Creative patent is not valid.

 

So i think id lawyers will give the green light to release the Source Code with the shadow system in.

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So i think id lawyers will give the green light to release the Source Code with the shadow system in.

 

Carmack has just stated that they were stalling on releasing it with the Carmack Reverse and that he's going to write new code to eliminate any issues they might have with Creative's patent entirely. Given that Carmack has had many years and a new engine behind him...I wouldn't be surprised if what he comes up with is even better than what was originally there. A fun little 'screw you' to Creative.

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It's highly unlikely that those other engines are using the "Carmack's reverse" algorithm.

 

It's very stupid that such a simple concept can be patented:

 

 

1) Start at the furthest point in the shadow volume

2) Am I within the line of sight of a shadow casting object?

3a) Yes, then draw a shadow on me and everything in the volume and exit

3b) No, then don't draw a shadow on me and move closer

4) Go to step 2 until the 3a is complete or we reach the shadow casting object

 

 

What's next:

 

I will patent the fastest algorithm to wash dishes...

 

I will patent the fastest way to stack rocks...

 

Pretty soon everyone will be forced to work inefficiently so they don't violate all these "valuable" patents. :rolleyes:

Edited by nbohr1more

Please visit TDM's IndieDB site and help promote the mod:

 

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It's highly unlikely that those other engines are using the "Carmack's reverse" algorithm.

 

It's very stupid that such a simple concept can be patented:

 

 

1) Start at the furthest point in the shadow volume

2) Am I within the line of sight of a shadow casting object?

3a) Yes, then draw a shadow on me and everything in the volume and exit

3b) No, then don't draw a shadow on me and move closer

4) Go to step 2 until the 3a is complete or we reach the shadow casting object

 

 

What's next:

 

I will patent the fastest algorithm to wash dishes...

 

I will patent the fastest way to stack rocks...

 

Pretty soon everyone will be forced to work inefficiently so they don't violate all these "valuable" patents. :rolleyes:

 

You probably lived under a rock the last few years, didn't you?

 

The entire software world is like that for years! Just look at Apple patenting the design of the ipad (a rounded rectangle with glossy surface), Microsoft extorting money from every Android device for trivial patents (the list was published a few days ago and contained such gems like "show the user a 'still loading' message inside the browser window) (and I bet MS gets more money per device than say the manufacturer of the display, or the battery), the trivial patents about the video encodings, the DVD and blueyray spec (yes, they came up with a spec on "how to store data on an external storage medium", and are now collection licenses from EVERY FRICKING PRESSED DISC, even tho all they did was draw up a list on "how to store the author, where to put the files etc.". you can read the stories how MS desperatedly wanted to be in the consortium, by adding their video codec to the list of "official codecs". Becaue everyone on that list gets royalities, no matter what codec is actually used...), the MP3 patent which essentially patents "lets throw away data the user isn't going to miss, anyway) (this time putting Germany to shame), and the list goes on and on and on.

 

Most patents these days are "XYZ ... on a mobile device!" whereas 3 years ago the same patents where "XYZ ... on the internet!". And before that it was "XYZ ... with a computer!". And XYZ isusually some trivial stuff where the patent took a laywer longer to write than an engeenier to come up with the solution when faced with the problem before breakfast...

 

Almost all software patents fall on the "it is trivial anyway" rule, most of them have prior art, anyway, and in the EU, you can't patent an algorithm (which all software essentially boils down to), anyway. But look at the US. The doubled their number of patents in the last 5 years or so....

 

 

Anyway, kudos to Carmarck to work around and from the inside of such a broken system.

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"The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." -- George Bernard Shaw (1856 - 1950)

 

"Remember: If the game lets you do it, it's not cheating." -- Xarax

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"Going back in and doing a little work on Doom 3 for the GPL release, I immediately missed persistant-across-runs console history."

He's really working to remove the problem!

Hat's off to him.

 

And that right there is why id will continue to get my business.

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Shadow volumes (Stencil Shadows) can't be patented period and there's many ways to render them, Creative only tried to patent a new way of doing them, for example Severance the Blade of darkness add real time perpixel/pervertex lighting and shadow volumes even before Doom3 and the Carmack reverse code in 2001, and if you only use shadow maps (that the majority of games use now) this patent don't even matters. BTW i find strange that being the patent invalid (because of prior art from nvidia) the id lawyers are stalling the release.

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Wow, that was fast. lol

 

Way to go Carmack!

 

Quick, someone patent a few issues we have, maybe he can fix them before release, too? :D

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"The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore, all progress depends on the unreasonable man." -- George Bernard Shaw (1856 - 1950)

 

"Remember: If the game lets you do it, it's not cheating." -- Xarax

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  • 2 weeks later...
The argument is that they encourage new innovation by insuring the research investments of companies.

 

Which is (probably) true in the case of pharmaceuticals and other products which are totally worthless until massive up-front investment has been made to bring them to market, but in the case of software which is based on minor incremental improvements to existing technologies it is complete bullshit, and has been confirmed as such by several studies along with the observation that massive advances in computer technology happened long before the invention of software patents (and/or in jurisdictions where software patents aren't valid and/or by individuals or groups who do not own any patents).

 

In general you won't find any experienced software developers or technologists arguing for software patents. There are basically three groups of people who want them:

  1. Patent lawyers, obviously, who make their living from litigating patent cases and are only too grateful for the extra work.
  2. Useless parasites like Microsoft and Intellectual Ventures who don't have the ability to create anything of value so they resort to extorting protection money from those who do.
  3. Credulous Kool-Aid drinkers who don't understand the issues and swallow the "patents protect innovation" propaganda; a category which includes a minority of internet commentators but sadly the majority of politicians, which is why the latter are only too happy to roll over and grant a legal monopoly on "innovations" like calling graphics functions in a slightly different order.

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