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ddragon

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ddragon
·há 3 anos·discuss
I fail to see how timing and luck isn't a factor. It's more than how popular it was when it launched, many of those languages that are allegedly better had a strong timing disadvantage by either not existing or not being mature once the data science boom occurred (including equivalents to libraries like numpy, scipy, matplotlib and theano), allowing python to be the right option then. Any language that missed the timing must now play catch up with a fraction of the resources and completely unproven in the market.

Luck is harder to quantify, but at the very least competitors like common lisp didn't have much of it.
ddragon
·há 3 anos·discuss
That would be simplifying too much. There are a lot of external factors for something being popular, like timing, luck, support from big enterprises and leading colleges, inertia and sunk costs. You could argue that does make python better regardless of the language itself but that poster was talking about a hypothetical scenario in which those factors were won by a language better designed for those tasks. Would you use python if most libraries, docs and support were elsewhere just for the language design as is today?
ddragon
·há 3 anos·discuss
I'm quite interested in the interactive thread pool (although I assume it works based on conventions of everyone playing nice). Julia seems to have a powerful parallelism model but it couldn't apply it to responsive GUI and web frameworks that requires low latency, so it is nice if you indeed can have for example the tasks handling HTTP request focusing on handling it as fast as possible while the background working threads dealing with larger computations use all the speed of the Julia language without being constantly interrupted.
ddragon
·há 5 anos·discuss
That issue actually doesn't happen with regular elixir, since it's immutable and stateless, the scheduler doesn't wait for the process to voluntarily wield (it's always safe to switch, so it just gives some fixed time for each process, which makes it very low latency and very reliable but not very efficient at any individual task due to all the switching). Calling other languages from erlang/elixir create dirty processes that can't be scheduled this way and may cause those issues.

Since I didn't use dirty processes in elixir it did make me forget about this obvious issue you pointed out, that for a mutable language like Julia can happen in every thread, but that's not something that limits the expressiveness of the model, but something that requires consideration to avoid while programming and language level mechanisms to protect the thread (at the very least the ability to define timeouts that can throw an exception on any spawned process) or maybe a future framework on top of it that handles this in a safer way (something like Akka). I can only hope Julia can achieve the full potential of it's multithreading model.
ddragon
·há 5 anos·discuss
I didn't go deep on Julia's multithreading, but what he is saying is that Julia uses an MxN threading (I think nowadays if you don't specify it at startup it will just use one for each cpu thread), which is the same as a language I did most of distributed programming (elixir/erlang), and as far as I know it's the same as Go.

Having 1 kernel thread for each CPU thread means that your program can use all available CPU threads at the same time (so you get all the parallelism available within the machine), and having a language based scheduler for each thread means you can have minimal overhead (no need to do a system call) to create a new concurrent execution (meaning lightweight/green threading similar to what python allows, except being automatically distributed by the language within all kernel/cpu threads). In Elixir this means you can create millions of processes even though the OS will only see one thread per logical cpu thread, and I never felt the limitation of this abstraction over multiprocessing (of course, Julia is definitely nowhere near as mature - and maybe never will due to stuff like preemptive scheduling and parallel garbage collection that is easier to implement in a language with only immutable types, though it seems to be moving along, and in Julia 1.7 the processes being able to move between kernel threads solving the issue mentioned in that discussion you linked).
ddragon
·há 5 anos·discuss
>6DOF gyro

A gyroscope is used to detect orientation/angular velocity (spinning), the sensor to add the other degrees of freedom is already there in most modern controllers and smartphones (the accelerometer). The issue is still accuracy I'm afraid.

>Do you need to rotate the yaw of your hand? Nope.

I'd certainly enjoy to open doors and make a simple goodbye gesture in VR.
ddragon
·há 5 anos·discuss
I mean, I had a vita and the gyroscope control was more accurate than the stick for shooters but that's because I'll naturally adjust if it overshoots (if I go to above I'll immediately push slightly down in a feedback loop - so here what really matters is the precision, not accuracy and in fact I can even adjust the sensitivity to my preference). That feedback loop with the user doesn't work well in VR, if my hand overshoots I don't have means of resetting the position (I can only compensate, but it's extremely uncomfortable when you feel your hand in position x, look at it and it's at position y and that x-y mapping will keep changing over time - and of course it's even worse with your head PoV not matching your head movements). Of course there are lots of issues as well, how do you get the perfect initial position? After all gyroscope/accelerometers only measure movement, it can't know where it starts (for example for jogging you need a gps to get a measurement of position, just like you need a camera/laser sensor for current VR). For gyroscope in traditional gaming you usually use the stick to adjust a solid start position, which is not possible in VR as well unless you force the user to stay in a perfect pose at the start of every level after inputting arms length and height as an example, which would definitely be annoying quickly if you need to reset frequently).

And finally, you example (splatoon 2) only needs to compute 2 degrees of freedom in movement (rotation left-right - or yawing, rotation down-up - or pitching, since rolling isn't relevant with a dot target), while VR systems depend on 6 degrees of freedom (yawing, pitching, rolling, elevating, strafing and surging - all of these for at least 3 devices at the same time: your head, left hand and right hand). Unfortunately controls in VR are quite complicated, and accelerometers, gyroscopes (and magnetometers which are also used in VR systems to know the reference to the floor) are simply insufficient (but necessary since the positional sensors can't keep track all time with occasional occlusion, such as having one hand passing over the other or leaving the tracking area), which is why the same sensors on the switch are used in every VR headset and controls in addition with even more sensors and algorithms.

EDIT: the camera system also helps a lot with defining gaming boundaries in the room and being able to quickly see if I accidentally leave it, I already punched my monitor once and that's with a barrier that always get visible when I approach something in my room.
ddragon
·há 5 anos·discuss
In my experience with a rift s, even though the oculus touch also has gyroscopes and accelerometers, they only help for a few seconds at most when the controllers leave the camera. Those sensors are just not accurate enough (I know little about the details of the sensors, but accelerometers are tracking the second derivative of the position, so any small error will accumulate fast when you want the latter), and you don't want to have your hand all over the place when you're trying to interact with things in VR, which is why, at least for now, you need to measure position directly for it to work, such as the camera/LED devices that are most popular with VR headsets and controllers (and even stuff like the PS Move controller).