Touch Buttons and Styluses

  • Rop's latest sample (M5Sound, in this forum) make me wonder what a reasonable, minimum size and spacing should be for TouchButtons. At almost 80 X 60 pixels, the DTMF buttons are usable, but already require some care with only 12 on the screen.
    I dug up an old passive capacitive stylus (the kind that looks like a soft pencil eraser) and found it increases speed and accuracy. Maybe a 50 X 50 pixel button would be usable with the passive stylus (doubling the number of buttons available.)
    I see that there are active capacitive styluses available with much smaller tips. Does anyone have one? Does it work well with the Core2?

  • I wrote a program to see what a reasonable minimum size touch button is:
    It's a test you play: it lets you choose what size button and what spacing; it makes a bunch of buttons and asks you to press eight of them. At some point you should stop getting perfect scores.
    I'd be interested in hearing what people find a usable minimum to be.

    Caution: to use this app, you need RopG's PR for M5Core2. You can download the touch button version of the lib here:

  • Hi Van

    thank you for the test application. I've added my test (using a finger) in the issues section. I think I have a stylus somewhere and when I find it I'll give it another go.