berkut

71 ms·

751.
by berkut 13y ago
No, the guy in the article was wrong - it's been possible to do in PRMan since at least 2000, but it was very slow (they didn't have any decent acceleration structures for the ray intersection), so it generally wasn't used that much. But it
752.
by berkut 13y ago
Ray differentials are just two extra rays one pixel up and right of the main ray to give the ray width. It's pretty trivial to keep them up to date with the main ray at surface intersections (it's technically more work, sure), but it's doab
753.
by berkut 13y ago
Unbiased actually isn't slow - Arnold has proved this - what's slow is using hundreds of bounces per path and bi-directional path tracing (like Maxwell, Indigo, LuxRender) which takes a lot longer. Biased generally means it's interpolated w
754.
by berkut 13y ago
Yes, because the article (and the person in it) doesn't seem to understand the difference between path tracing (ray tracing with global illumination - multiple bounces even with diffuse surfaces), and ray tracing = sending rays around a sce
755.
by berkut 13y ago
They're using uni-directional path tracing - if they're using PRMan 17 (Which I think they were), it'll probably be unbiased like with Arnold. So it's unbiased, but unidirectional, unlike LuxRender's MLT (two-way path tracing). PRMan 17's a
756.
by berkut 13y ago
Yeah, they're starting to use off-the-shelf software a lot more recently...
757.
by berkut 13y ago
Yes, it makes a lot of difference. There's the obvious render time, but actually render time isn't that important - studios are happy to wait up to 30 hours for a 4k frame on the farm if that's what it takes for a shot. But they don't want
758.
by berkut 13y ago
Pixar's generally ahead in terms of story, animation (they hand-animate everything) and look (shading and lighting), but in terms of pure tech, other companies like Weta, ILM and SPI are generally ahead of them as they work on multiple show
759.
by berkut 13y ago
This is wrong actually - they've been using ray tracing for ages (all ambient occlusion in PRMan is done with raytracing, by sending out occlusion rays in a hemisphere around the shading point). What's new with MU is they're using both phys
760.
by berkut 13y ago
> BTW, have you heard that the next Haswell processors can get only 5% performance improvement? Bollocks - using the new gather AVX instructions, I've seen close to a 40% increase over IB on some floating-point code I've hand-written wi
761.
by berkut 13y ago
This is used a lot for things like acceleration structures in 3D graphics - you also get the benefit of being able to store an uint32_t offset instead of a 64-bit pointer, fitting a bigger tree in memory/cache.
762.
by berkut 13y ago
In performance-critical code, this is well known. Also, since the 64-bit days, storing linked lists also has a significant overhead over arrays due to the additional storage requirements of the pointers, which means you fit less in cache wh
763.
by berkut 13y ago
I think it's so that the Game VM can stay constant, and game developers can develop for that for the next ~6 years knowing each XBox will have exactly the same behaviour, whereas the third one for TV services and internet can be continually
764.
by berkut 13y ago
I certainly hope not.
765.
by berkut 13y ago
Most definitely - on a modern multitasking operating system your "all types of pauses" is generally only synchronous IO issues to disk or network - as long as you've got spare CPU available to your process/threads and you're sensible with y
766.
by berkut 13y ago
Not if it's done subtly (5-8% transparency) - if you've got multiple windows in a screen, it greatly enhances context in terms of what windows are where.
767.
by berkut 14y ago
Free desktop apps I assume you mean - there's a plethora of high-end VFX desktop apps available on Linux.
768.
by berkut 14y ago
This is what I don't understand - a lot of these WebGL demos as well are largely equivalent (minus some pixel shader stuff that couldn't be done back then) to OpenGL stuff that was being done back in 2000.
769.
by berkut 14y ago
What's it built in? Java I'd imagine? IntelliJ was almost perfect for Java (last used it 3 years ago), other than the ridiculous memory usage and the constant freezing which I'm pretty sure the JVM's GC was responsible for. I've been using
770.
PDF: NSA were planning IBM supercluster with 157 GB of storage in 1977(cryptome.org)
2 points by berkut 14y ago|0 comments
771.
by berkut 14y ago
I disagree - I starting learning C++ at 14, and I had shareware apps for Windows I was making a fair amount of money with by the time I was 17 back in the late 90s... That included learning how the POP3 and SMTP protocols worked to write em
772.
by berkut 14y ago
In my experience writing high end VFX software for three platforms, Linux's libc is the slowest with normal maths functions, and Windows is the fastest. Intel's math libs are often 4-5x times faster - if you do a microbenchmark of a loop of
773.
by berkut 14y ago
It's much better at vectorising code (using SSE and AVX) than MSVC and GCC, it's got better loop unrolling heuristics (it's better at working out when unrolling isn't worth it or will slow things down), and its maths functions are much fast
774.
by berkut 14y ago
You can produce work that looks good, as they technically have the features, but the workflow is generally atrocious for open source tools. This means it takes a lot longer to do stuff. On top of this, the technical limitations of GIMP
775.
by berkut 14y ago
Fair point, yeah it's internal with them, I hadn't thought of that. Put it this way - they've bought Nuke three times, and they made it originally!
776.
by berkut 14y ago
But that's inherently a problem with feature film (and especially animation stuff) - even the studios like FOX and Disney only get the profit once DVDs and merchandise have been selling - before then, they've given out millions to finance t
777.
by berkut 14y ago
A lot of the more mundane stuff is already "outsourced" or given to VFX houses' offices in other parts of the world like India. e.g. SPI send all their Roto to India, they've just moved all their comping and lighting to Vancouver, it's main
778.
by berkut 14y ago
It's artist time that is expensive - even render time is cheap in comparison. VFX houses are happy to spend loads of money on renderfarms and wait 12 hours a frame, but it's mainly artist time that costs money. Software cost only has a smal
779.
by berkut 14y ago
Yeah, it makes the for line shorter. We sometimes hoist the end iterator as well, as often g++ can't optimise out the call to .end() each iteration - it can if there's a ref to a const item and you call end() on that const ref, but otherwis
780.
by berkut 14y ago
We did - loads of Qt and std:: stuff - admittedly we used a custom memory allocator for the std:: stuff, but it worked fine.

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