5 ms·

To get an idea of the impact and importance of touch latency, see this intriguing demo by the Microsoft Applied Sciences Group: https://youtube.com/watch?v=vOvQ

by kmfrk 13y ago

To get an idea of the impact and importance of touch latency, see this intriguing demo by the Microsoft Applied Sciences Group: https://youtube.com/watch?v=vOvQCPLkPt4 https://youtube.com/watch?v=vOvQCPLkPt4. Drawing is one of those things that has felt awful on iOS devices to me.

joeblau 13y ago
That video was a great. Thanks for sharing it.
- kmfrk 13y ago
  It's one of my favourite technology videos/demos of all time. Every time someone criticizes Microsoft, I remember this video, knowing Microsoft's failures aren't for lack of talent.
  - theon144 13y ago
    Sadly, Microsoft's research group and just about everyone else at Microsoft aren't the same people at all :\
Pxtl 13y ago
Yep. There's a decent homebrew paint app on the Nintendo DS that runs circles around the smartphone counterparts... The Ds has a joke of a processor, terrible resolution, and no memory worth mentioning. But it has a resistive pressure-sensitive touchscreen and a stylus. That's enough to make a huge difference. Resistive touchscreens are fast and pressure sensitive, allowing far better conditions for art.
- aikinai 13y ago
  The sad thing is that official games aren't allowed to support the pressure-sensitivity provided by the DS hardware, so it's only used in homebrew apps like the paint app you mentioned.
  - MBCook 13y ago
    Do you know why that is? For example, does the pressure-sensitivy vary wildly between individual screens?
    - Pxtl 13y ago
      Incredibly so. Calibrating the aforementioned paint app is a huge bitch. But it's great afterwards.
      - archagon 13y ago
        I remember reading somewhere that the DS homebrew "pressure sensitivity" was merely a hack. Since you hit more neighboring pixels when you push the stylus down, you get more "pressure". (This could be outdated information, though.)
coldtea 13y ago
>Drawing is one of those things that has felt awful on iOS devices to me. Compared to what, since, according to TFA they have the smallest touch latency? Perhaps you haven't tried the right apps. Most drawing apps (including major names, like Autodesk's) have slow-ass drawing code. Heck, some painting apps are even slow on my iMac (Corel Painter, ArtRage). That's not because of "touch latency" though. It's because of slow draw engines. And I say that, because I've seen apps with very fast responsiveness. Try Procreate ( http://procreate.si/ http://procreate.si/ ), which uses the fastest engine I've seen (specially coded in OpenGL and 3D-accelerated). And check the artwork created with it by some of the community users (there are 2-3 videos on their site it's AMAZING). Two other apps I found fast (but not as fast) are: Ideas, by Adobe, and Paper.
- kmfrk 13y ago
  Compared to what Paper, dude(tte)! The analogue, lowercase-letter kind. :) Paper and Procreate are excellent apps, but the input lag is very noticeable on my iPad 3; if you move your finger really fast and stop, you can see that it takes a short amount of time, before the drawn line catches your finger. It wasn't long ago that dead-tree books were preferable to tablets, before Retina was a thing. And you could still argue print books are preferable. Sometimes, the best Technology can achieve is the bar set by the non-digital world, and until then, it's going to feel grating to pedantic curmudgeons like yours truly. :) +++ EDIT: A closing thought. The highest bar is always human perception: (1) The optimal FPS for a videogame is, to my knowledge, 60. (2) The optimal display resolution for a reading device is, TMK, ~326 PPI (Retina). That is the goal. Anything lower than that will stick out and annoy people like me. Anything higher is not for the engineers, but the marketing department.
  - lukeschlather 13y ago
    have you tried the microsoft surface pro?
    - kmfrk 13y ago
      Nope - I haven't even seen one!
mistercow 13y ago
Of course the video is a little bit misleading when it talks about 1ms refresh, since touch response stops being the limiting factor before that point. AFAIK the fastest refresh rate for any phone on the market is 250Hz. That's 4ms refresh, which is great, but of course you also have to factor in time to actually process the touch event, change the image, and render it.
- nrivadeneira 13y ago
  It's not misleading at all. They specifically said it was a test setup and stated that their aim is to be at around 1ms latency in the next decade. Obviously that means working on the other limiting factors to get there as well. It's not like they'll just try to get the touch response to 1ms and ignore screen refresh rates.
- rorrr2 13y ago
  If we want a 60Hz app, the touch latency + processing + display shouldn't exceed 16.7ms. 1ms touch latency would be nice indeed, but I think 5-8ms would work just as well on most devices.
neonkiwi 13y ago
I've done some research which involved the perceptual effects of latency, so I was interested in the test rig from their video and found a paper they published in ACM about it: http://edgey.com/wp-content/uploads/2013/01/p453-ng.pdf http://edgey.com/wp-content/uploads/2013/01/p453-ng.pdf Turns out that to achieve this 1ms latency system (once you have that, it's simple to add artificial latency) they had an FPGA directly processing touch data from a resistive sensor over a 2 MBps serial (optical) connection, computing the center of mass and directly driving a DLP projection display so that parallax between the surface being touched and the display would be eliminated. Nice rig!

by kmfrk 13y ago

joeblau 13y ago

That video was a great. Thanks for sharing it.

kmfrk 13y ago
It's one of my favourite technology videos/demos of all time. Every time someone criticizes Microsoft, I remember this video, knowing Microsoft's failures aren't for lack of talent.
- theon144 13y ago
  Sadly, Microsoft's research group and just about everyone else at Microsoft aren't the same people at all :\

Pxtl 13y ago

Yep. There's a decent homebrew paint app on the Nintendo DS that runs circles around the smartphone counterparts... The Ds has a joke of a processor, terrible resolution, and no memory worth mentioning. But it has a resistive pressure-sensitive touchscreen and a stylus. That's enough to make a huge difference. Resistive touchscreens are fast and pressure sensitive, allowing far better conditions for art.

aikinai 13y ago
The sad thing is that official games aren't allowed to support the pressure-sensitivity provided by the DS hardware, so it's only used in homebrew apps like the paint app you mentioned.
- MBCook 13y ago
  Do you know why that is? For example, does the pressure-sensitivy vary wildly between individual screens?
  - Pxtl 13y ago
    Incredibly so. Calibrating the aforementioned paint app is a huge bitch. But it's great afterwards.
    - archagon 13y ago
      I remember reading somewhere that the DS homebrew "pressure sensitivity" was merely a hack. Since you hit more neighboring pixels when you push the stylus down, you get more "pressure". (This could be outdated information, though.)

coldtea 13y ago

>Drawing is one of those things that has felt awful on iOS devices to me. Compared to what, since, according to TFA they have the smallest touch latency? Perhaps you haven't tried the right apps. Most drawing apps (including major names, like Autodesk's) have slow-ass drawing code. Heck, some painting apps are even slow on my iMac (Corel Painter, ArtRage). That's not because of "touch latency" though. It's because of slow draw engines. And I say that, because I've seen apps with very fast responsiveness. Try Procreate ( http://procreate.si/ http://procreate.si/ ), which uses the fastest engine I've seen (specially coded in OpenGL and 3D-accelerated). And check the artwork created with it by some of the community users (there are 2-3 videos on their site it's AMAZING). Two other apps I found fast (but not as fast) are: Ideas, by Adobe, and Paper.

kmfrk 13y ago
Compared to what Paper, dude(tte)! The analogue, lowercase-letter kind. :) Paper and Procreate are excellent apps, but the input lag is very noticeable on my iPad 3; if you move your finger really fast and stop, you can see that it takes a short amount of time, before the drawn line catches your finger. It wasn't long ago that dead-tree books were preferable to tablets, before Retina was a thing. And you could still argue print books are preferable. Sometimes, the best Technology can achieve is the bar set by the non-digital world, and until then, it's going to feel grating to pedantic curmudgeons like yours truly. :) +++ EDIT: A closing thought. The highest bar is always human perception: (1) The optimal FPS for a videogame is, to my knowledge, 60. (2) The optimal display resolution for a reading device is, TMK, ~326 PPI (Retina). That is the goal. Anything lower than that will stick out and annoy people like me. Anything higher is not for the engineers, but the marketing department.
- lukeschlather 13y ago
  have you tried the microsoft surface pro?
  - kmfrk 13y ago
    Nope - I haven't even seen one!

mistercow 13y ago

Of course the video is a little bit misleading when it talks about 1ms refresh, since touch response stops being the limiting factor before that point. AFAIK the fastest refresh rate for any phone on the market is 250Hz. That's 4ms refresh, which is great, but of course you also have to factor in time to actually process the touch event, change the image, and render it.

nrivadeneira 13y ago
It's not misleading at all. They specifically said it was a test setup and stated that their aim is to be at around 1ms latency in the next decade. Obviously that means working on the other limiting factors to get there as well. It's not like they'll just try to get the touch response to 1ms and ignore screen refresh rates.
rorrr2 13y ago
If we want a 60Hz app, the touch latency + processing + display shouldn't exceed 16.7ms. 1ms touch latency would be nice indeed, but I think 5-8ms would work just as well on most devices.

neonkiwi 13y ago

I've done some research which involved the perceptual effects of latency, so I was interested in the test rig from their video and found a paper they published in ACM about it: http://edgey.com/wp-content/uploads/2013/01/p453-ng.pdf http://edgey.com/wp-content/uploads/2013/01/p453-ng.pdf Turns out that to achieve this 1ms latency system (once you have that, it's simple to add artificial latency) they had an FPGA directly processing touch data from a resistive sensor over a 2 MBps serial (optical) connection, computing the center of mass and directly driving a DLP projection display so that parallax between the surface being touched and the display would be eliminated. Nice rig!