| # Input Device Calibration File |
| |
| # Touch Area |
| touch.touchArea.calibration = pressure |
| |
| # Tool Area |
| # Raw width field measures approx. 1 unit per millimeter |
| # of tool area on the surface where a raw width of 14 corresponds |
| # to about 18mm of physical size. Given that the display resolution |
| # is 6px per mm we obtain a scale factor of 6 pixels / unit and |
| # a bias of 24 pixels. Each contact point is measured independently |
| # so the raw width is not a sum. |
| # |
| # The linear approximation isn't particularly good here. We |
| # might want to use a second order polynomial fit instead since the width |
| # appears to scale with touch area as opposed to with touch diameter. |
| # |
| # Calibration measurements: |
| # 13mm -> raw width = 7-8 |
| # 14mm -> raw width = 8-9 |
| # 17mm -> raw width = 12-13 |
| # 18mm -> raw width = 14-15 |
| # 19mm -> raw width = 15-16 |
| # 21mm -> raw width = 17-19 |
| # 24mm -> raw width = 23-26 |
| touch.toolArea.calibration = linear |
| touch.toolArea.linearScale = 6 |
| touch.toolArea.linearBias = 24 |
| touch.toolArea.isSummed = 0 |
| |
| # Pressure |
| # Driver reports signal strength as pressure. |
| # A normal thumb touch while touching the back of the device |
| # typically registers about 80 signal strength units although |
| # this value is highly variable and is sensitive to contact area, |
| # manner of contact and environmental conditions. We set the |
| # scale so that a normal touch with good signal strength will be |
| # reported as having a pressure somewhere in the vicinity of 1.0, |
| # a featherlight touch will be below 1.0 and a heavy or large touch |
| # will be above 1.0. We don't expect these values to be accurate. |
| touch.pressure.calibration = amplitude |
| touch.pressure.source = default |
| touch.pressure.scale = 0.0125 |
| |
| # Size |
| touch.size.calibration = normalized |
| |
| # Orientation |
| touch.orientation.calibration = none |
| |