// Draw a spot and wait until the user touches it, returning the touch coordinates in tx and ty.
// The alternative X and Y locations are so that the caller can allow for the touch panel being possibly inverted.
void DoTouchCalib(PixelNumber x, PixelNumber y, PixelNumber altX, PixelNumber altY, bool wantY, uint16_t& rawRslt)
{
const PixelNumber touchCircleRadius = 8;
const PixelNumber touchCalibMaxError = 40;
lcd.setColor(touchSpotColour);
lcd.fillCircle(x, y, touchCircleRadius);
for (;;)
{
uint16_t tx, ty, rawX, rawY;
if (touch.read(tx, ty, &rawX, &rawY))
{
if ( (abs((int)tx - (int)x) <= touchCalibMaxError || abs((int)tx - (int)altX) <= touchCalibMaxError)
&& (abs((int)ty - (int)y) <= touchCalibMaxError || abs((int)ty - (int)altY) <= touchCalibMaxError)
)
{
TouchBeep();
rawRslt = (wantY) ? rawY : rawX;
break;
}
}
}
lcd.setColor(defaultBackColour);
lcd.fillCircle(x, y, touchCircleRadius);
}
