ViewWidget::~ViewWidget()
{
if (showAxes() && _sceneRoot)
_sceneRoot->removeChild(getAxes());
if (showGrids() && _sceneRoot)
_sceneRoot->removeChild(getXYGrid());
delete _widget;
delete compassAxes;
}
// sample configured channels and plot them
// this function is called from the sampling timer - there should be no y-axis showing
void Plotter::sample() {
float xValue; // x coordinate, value
uint16_t xVal; // x coordinate, screen pixels
uint8_t eraseWidth;
uint16_t xAxisPosition, yAxisPosition;
switch (style) {
case scan:
xValue = millis() - startTime + xMin; // ms elapsed since capture began
if (xValue >= xMax) { // if the time-axis has filled up
startTime = millis(); // and reset the x-axis timer
xValue = xMin; // should wrap
}
xVal = getScreenX(xValue);
eraseWidth = min(5,xo+width-xVal-1); // clearing out previous data just ahead
xAxisPosition = getScreenY(axesY); // height of x-axis
yAxisPosition = getScreenX(axesX); // position of y-axis
tft.fillRect(xVal+1, yo, eraseWidth, height, PLOTTER_BACKGROUND);
if (axes) {
tft.drawFastHLine(xVal+1, xAxisPosition, eraseWidth, PLOTTER_BORDER); // replace possibly-erased x-axis segment
if (yAxisPosition >= xVal && yAxisPosition < xVal + eraseWidth ) {tft.drawFastVLine(yAxisPosition, yo, height, PLOTTER_BORDER);} // replace erased y-axis
}
break;
case track:
trackCounter++;
if (trackCounter >= xo + width) {
trackCounter = xo;
clear(); // OK to take the time to clear the screen
if (axes) { showAxes(); } // tracking is not meant to be fast anyway
}
xVal = trackCounter;
break;
default:
xVal = xo;
}
for (int i=0; i<nChannels; i++) {
float yValue = channels[i].sample();
tft.drawPixel(xVal, getScreenY(yValue), channels[i].getColor());
}
sampleTimer.reset(); // reset the timer for the next sample
}
