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Comment: Re:What about OpenCL 1.2 support? (Score 3, Interesting) 59

Mantle is less an open specification than CUDA is, CUDA does have a full x86 implementation available which is mostly slower due the CPU not taking too much advantage of the massive parallelism of the GPU (not sure about how this play out with Xeon Phi).

Mantle on the other hand is a very low level Graphics API that basically exposes SW to some low level interactions with AMD's GPU. It's more like GLIDE than OpenCL. From what I've seen so far it's not clear to me Mantle will be very portable across several AMD generations. It works for GCN based cards out now but who knows if it will be fast for GCN++ without a major rewrite of the application. NVIDIA could implement Mantle but would probably have to translate so much stuff in SW to make it work you'd lose the low SW overhead.

From the one or two talks I listened to Mantle seems to basically expose the same interface the driver developers have access to and lets you go to town. This is great for the latest architecture but now it's up to your application to evolve as the HW does. There's a whole lot of work being done to optimize for each architecture release in the driver which allow older games that the publisher doesn't really want to support anymore to work and see performance boosts.

Comment: Nothing easy but Udacity can help (Score 5, Informative) 198

by Jthon (#44332381) Attached to: Ask Slashdot: What Is the Most Painless Intro To GPU Programming?

So there's nothing really easy about GPU programming. You can look at C++ AMP from Microsoft, OpenMP or one of the other abstractions but you really need to understand how these massively parallel machines work. It's possible to write some perfectly valid code in any of these environments which will run SLOWER than on the CPU because you didn't understand fundamentally how GPUs excel at processing.

Udacity currently has a fairly decent intro course on GPU programming at: https://www.udacity.com/course/cs344

It's based around NVIDIA and CUDA but most of the concepts in the course can be applied to OpenCL or another GPU programming API with a little syntax translation. Also you can do everything for the course in your web-browser and you don't need an NVIDIA GPU to finish the course exercises.

I'd suggest running through that and then deciding on what API you want to end up using.

Comment: Re:Change the DPI setting (Score 3, Insightful) 234

by Jthon (#42149361) Attached to: Ask Slashdot: Good Linux Desktop Environment For Hi-Def/Retina Displays?

Your comment shows a lack of understanding as to what DPI is supposed to be used for since DPI shouldn't control scaling.

DPI stands for dots per inch, and you should configure that setting to match the actual number of dots per inch of your display. Then the SW environment should support some sort of sliding scale to let you change the size of any UI elements.

Sadly most desktop platforms don't do this correctly and bind the DPI to the size of UI elements. I will admit that resolution independence isn't easy, Microsoft didn't really start down that path until Windows 7, and Apple didn't start to get close until Mountain Lion.

Having used a retina display Mac it irritates me that they don't just have a slider to set UI scale, but instead you can select from several pre-set resolutions. I suspect this is because many applications still try to plot stuff pixel by pixel and so can't scale arbitrarily. It's not easy for most SW to be truly resolution independent and it seems most developers seem to skip handling that sanely on all platforms.

Comment: Not entirely a FB bug, phone software is the prob (Score 2) 178

by Jthon (#40534245) Attached to: Facebook API Bug Deletes Contact Info On Phones

The Facebook bug here is that if you ask Facebook for someone's email, it was returning the last one added which was that stupid @facebook.com email. But why was the phone deleting contact info and replacing it? If your only source of contact data for a person was their Facebook email then yeah I can see that swapping, but why isn't the phone keeping Facebook, and other contact info separate?

My phone shouldn't see Facebook info change, then go and delete the work email from my Google contacts, or phone contact. If these phones are doing that I'd argue you have a phone SW bug. I wouldn't want any random sync service to suddenly override my manually entered contact data.

As for people complaining about work emails being swapped, why do you sync work emails via facebook? You should have that entered into a separate place. My Android phone is smart enough to keep google contacts and facebook contacts separate, and merge the accounts for display purposes. (And my old Palm Pre back in the day did an even better job of this.)

Comment: Re:From Wikipedia... (Score 4, Informative) 627

by Jthon (#37389350) Attached to: "Wi-Fi Refugees" Shelter in West Virginia Mountains

That's not radiation, that's because cheap CRTs tubes oscillate at 60 hertz and if you're not deaf in the upper frequencies you can hear them whine. Basically it's noise from the flyback transformer in the CRT. Many children can hear them but people often lose those frequencies as they get older.

I can still hear when a cheap CRT is on but I don't claim to be allergic to wifi.

See http://www.pcguide.com/ts/x/comp/crt/failWhine-c.html for some more info.

Comment: Re:Carmack (Score 4, Insightful) 616

by Jthon (#37133016) Attached to: C++ 2011 and the Return of Native Code

I think there was a hope that computing power would catch up and make VMs a competitive alternative to native code.

While you're right there's a computing power issue here, the issue is battery life not lack of CPU cycles. VMs add overhead, as you add overhead you'll run longer and burn more power on the CPU. If you want to squeeze all you can out of a limited battery you need to optimize your code and in the end that's going to mean native code with very explicit memory management. VMs just don't play well in embedded environments.

Comment: Re:Just Bizarre (Score 1) 722

by Jthon (#36769084) Attached to: Netflix Deflects Rage Over Price Increase

I'm pretty sure the real goal is to force you to choose one or the other. In the long term I think they plan to drop or spin off the DVD business and become a 100% streaming company. I think they're hoping that everyone just decides that having both is too much money and choose to just stream. If everyone would just switch to the DVD only plan they'd probably rethink this strategy.

What annoys me is that they don't have a 3 DVD out at a time plan without streaming. My ages old plan is getting a massive rate hike come Sept. They still have too much DVD only content for me to really think that their rate hike is justified.

Comment: Re:Interesting Highlights (Score 1) 279

by Jthon (#36376636) Attached to: Apple Plans New Spaceship-like Campus

Apple's already across the street, I doubt traffic would get too much worse since this place is right next to the freeway. Though at the moment Apple is spread out all over that area and now they'd be concentrating all those people into a couple blocks. Luckily I don't need to drive past Homestead and Wolfe all that often :D.

Comment: Re:This is why I don't work for Microsoft (Score 1) 282

by Jthon (#35843064) Attached to: Ex-MS GM Can't Work 'Anywhere In the World' For Salesforce

I asked if they would alter the agreement to strike the non-compete terms but he said they wouldn't do that. I know better than to accept some verbal assurance from a recruiter vs what the contract says. That's like believing that guy at BestBuy that your extended warranty covers the battery in an iPod (it won't). While at the time I didn't think I would have left MS very soon I was afraid that if I was a good performer that they'd be even more likely to try and enforce such a non-compete. I'm sure they let it slide if you suck at your job.

The trick here is that he got sued in WA court. I've heard of some companies trying to take the action up in CA first on such contract since CA courts would side with the employee as such terms are considered unconscionable in CA.

"We don't care. We don't have to. We're the Phone Company."