This story made the Shortbread yesterday, but we'd be remiss not to mention it more prominently. You may have been wondering what was behind the recently announced "agreement" between id Software and Creative that will bring EAX tech to DOOM 3. Turns out Creative had a software patent on the shadowing technique known, in one of the great ironies in the annals of patents and prior art, as "Carmack's reverse." Beyond3D managed to get a quick comment out of Mr. Carmack about patents in general and about what happened in this case:
The patent situation well and truly sucks.Apparently, NVIDIA's Sim Dietrich described this technique to attendees of a Creative developer's forum, according to a forum post from September 2003 that's linked from the HardOCP:
We were prepared to use a two-pass algorithm that gave equivalent results at a speed hit, but we negotiated the deal with Creative so that we were able to use the zfail method without having to actually pay any cash. It was tempting to take a stand and say that our products were never going to use any advanced Creative/3dlabs products because of their position on patenting gaming software algorithms, but that would only have hurt the users.
Don't worry about it fellas. I described this technique publicly a few months before they filed the patent - hence Prior Art. Ironically, it was at a Creative Labs developer's forum. During my stencil buffer talk, I described doing shadow volumes the 'reverse' way. At the time, I didn't realize the major reason why the z fail method is better than the z pass method, although I did realize they were logically equivalent, which is why it's now known as 'Carmack's Reverse' and not 'Dietrich's Reverse'!So John gets naming rights from the gentlemanly Dietrich for first figuring out how and why this technique is particularly helpful, but Creative gets the patent from Uncle Sam for filing the appropriate paperwork. Despite the clear examples of prior art, id didn't care to tangle with Creative in court over it.
For Creative's take on the matter, see this story at the Inq.
|Agon AG352UCG serves up curved G-Sync gaming at 100Hz||7|
|BlackWidow Chroma V2 arrives with Razer's Yellow switches||11|
|Toshiba N300 hard drives are ready for NAS service||10|
|GeForce 378.49 drivers are ready to face Resident Evil 7||12|
|Google Voice gets a long-overdue update||9|
|iOS 10.2.1 update plugs multiple security holes||8|
|Android apps coming to all future Chromebooks||9|
|Steam client lets users move games and use Xbox controllers||14|
|Samsung Galaxy S8 phones won't appear at MWC||12|
|Face it. We all know the success of PC Gaming is because of the invention of the RGB LED.||+54|