hubriz · HackerTrans

Writing in JS is a sacrifice of performance in the first place. Besides even the smartest, most performant library in the hands of inept programmer will produce a subpar result. If you're smart, you can write quality, performant code with both _ as well as Sugar, I bet. Besides sugar is a much more diverse set of functions as far as I can tell. I like the idea and are willing to try it out. :)

hubriz

15 anni fadiscuss

That is only partially correct. As mentioned before, there are two types of WebGL canvas contexts out there: webgl and experimental-webgl. Former does not put the GLX_ARB_create_context_robustness extension in place, which is basically what you're referring to.

hubriz

15 anni fadiscuss

Up until now SL has supported pixel shaders, nothing more.

hubriz

15 anni fadiscuss

> doesnt seem like a large assumption

It is for the reason I've mentioned before: XNA abstracts out pretty much everything. With XNA you're not programming to the metal anymore, which is unfortunately true with WebGL. The greatest concern seems to be with the way OGL handles various buffers. For example in WebGL it is possible to create bufferData stating that it's of size X and provide Y values with Y much smaller than X. What you get is a buffer full of stale data from the memory. Bad idea.

Also there's much less "stuff" you can break in XNA with lower profile levels (feature sets) which are suitable for the web. E.g. you can't write shaders for the mobile devices today for both security and perf reasons. You get a preset amount of them and that's it. Yes, it's limiting, but you can't choke GPU to death and you can't submit shader payload that's known to crash given driver.

It's all about false equivalence that author makes in his blog entry. Problems exist with pretty much every piece of advanced software. But you can add small attack vector, or a large one. They are not equal and making it seem otherwise is bogus.

JS is amazing and I love 2D canvas. But WebGL is trying to put low-level stuff in the high-level code. It's awesome in terms of performance, but is inherently fragile and may be abused easily. It seems that it's not sensible programmers MS is afraid of but malicious attackers. And it's very unlikely that WebGL won't be happily abused.

As for Carmack, he stated at various occasions that he's closely following web graphics. He's also more than knowledgeable about the issues with drivers, how they can be hit even accidentally and how (un)likely it is for hardware vendor to fix them timely.

Also aside from the security, drawing from my experience, it is extremely difficult to make semi-advanced graphics code perform well and look acceptably similar on different GPUs. This is something APIs exposed in the high-level languages (which JS I think undeniably is) should hide from the developer, not dump on him. The fact that there are two different 3D canvas contexts - webgl and experimental-webgl - doesn't really help.

hubriz

15 anni fadiscuss

What a bunch of lies this is. Silverlight has nothing to do with XNA linked by the author. But even if we assume that SL5 uses XNA, XNA does not expose raw buffers in the code the way WebGL does and it does not allow one to write shaders on the mobile devices (one of the attack vectors mentioned in the MS article). SL itself does let you write PS (FS if you're from OGL crowd) and yes, this is an attack vector. But comparing this to WebGL is a false equivalence.

I find it amusing that even John Carmack (strong OGL supporter) agrees with MS on this one yet it is some random Google employee who gets his word spread. This author knows FUD very well, I give him that. He's proficient in spreading it.

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