void KisToolFreehandHelper::paint(KoPointerEvent *event)
{
KisPaintInformation info =
m_d->infoBuilder->continueStroke(event,
elapsedStrokeTime());
info.setCanvasRotation( m_d->canvasRotation );
info.setCanvasHorizontalMirrorState( m_d->canvasMirroredH );
KisUpdateTimeMonitor::instance()->reportMouseMove(info.pos());
/**
* Smooth the coordinates out using the history and the
* distance. This is a heavily modified version of an algo used in
* Gimp and described in https://bugs.kde.org/show_bug.cgi?id=281267 and
* http://www24.atwiki.jp/sigetch_2007/pages/17.html. The main
* differences are:
*
* 1) It uses 'distance' instead of 'velocity', since time
* measurements are too unstable in realworld environment
*
* 2) There is no 'Quality' parameter, since the number of samples
* is calculated automatically
*
* 3) 'Tail Aggressiveness' is used for controling the end of the
* stroke
*
* 4) The formila is a little bit different: 'Distance' parameter
* stands for $3 \Sigma$
*/
if (m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::WEIGHTED_SMOOTHING
&& m_d->smoothingOptions->smoothnessDistance() > 0.0) {
{ // initialize current distance
QPointF prevPos;
if (!m_d->history.isEmpty()) {
const KisPaintInformation &prevPi = m_d->history.last();
prevPos = prevPi.pos();
} else {
prevPos = m_d->previousPaintInformation.pos();
}
qreal currentDistance = QVector2D(info.pos() - prevPos).length();
m_d->distanceHistory.append(currentDistance);
}
m_d->history.append(info);
qreal x = 0.0;
qreal y = 0.0;
if (m_d->history.size() > 3) {
const qreal sigma = m_d->effectiveSmoothnessDistance() / 3.0; // '3.0' for (3 * sigma) range
qreal gaussianWeight = 1 / (sqrt(2 * M_PI) * sigma);
qreal gaussianWeight2 = sigma * sigma;
qreal distanceSum = 0.0;
qreal scaleSum = 0.0;
qreal pressure = 0.0;
qreal baseRate = 0.0;
Q_ASSERT(m_d->history.size() == m_d->distanceHistory.size());
for (int i = m_d->history.size() - 1; i >= 0; i--) {
qreal rate = 0.0;
const KisPaintInformation nextInfo = m_d->history.at(i);
double distance = m_d->distanceHistory.at(i);
Q_ASSERT(distance >= 0.0);
qreal pressureGrad = 0.0;
if (i < m_d->history.size() - 1) {
pressureGrad = nextInfo.pressure() - m_d->history.at(i + 1).pressure();
const qreal tailAgressiveness = 40.0 * m_d->smoothingOptions->tailAggressiveness();
if (pressureGrad > 0.0 ) {
pressureGrad *= tailAgressiveness * (1.0 - nextInfo.pressure());
distance += pressureGrad * 3.0 * sigma; // (3 * sigma) --- holds > 90% of the region
}
}
if (gaussianWeight2 != 0.0) {
distanceSum += distance;
rate = gaussianWeight * exp(-distanceSum * distanceSum / (2 * gaussianWeight2));
}
if (m_d->history.size() - i == 1) {
baseRate = rate;
} else if (baseRate / rate > 100) {
break;
}
scaleSum += rate;
x += rate * nextInfo.pos().x();
y += rate * nextInfo.pos().y();
if (m_d->smoothingOptions->smoothPressure()) {
pressure += rate * nextInfo.pressure();
}
}
if (scaleSum != 0.0) {
x /= scaleSum;
y /= scaleSum;
if (m_d->smoothingOptions->smoothPressure()) {
pressure /= scaleSum;
}
}
if ((x != 0.0 && y != 0.0) || (x == info.pos().x() && y == info.pos().y())) {
info.setPos(QPointF(x, y));
if (m_d->smoothingOptions->smoothPressure()) {
info.setPressure(pressure);
}
m_d->history.last() = info;
}
}
}
if (m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::SIMPLE_SMOOTHING
|| m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::WEIGHTED_SMOOTHING)
{
// Now paint between the coordinates, using the bezier curve interpolation
if (!m_d->haveTangent) {
m_d->haveTangent = true;
m_d->previousTangent =
(info.pos() - m_d->previousPaintInformation.pos()) /
qMax(qreal(1.0), info.currentTime() - m_d->previousPaintInformation.currentTime());
} else {
QPointF newTangent = (info.pos() - m_d->olderPaintInformation.pos()) /
qMax(qreal(1.0), info.currentTime() - m_d->olderPaintInformation.currentTime());
paintBezierSegment(m_d->olderPaintInformation, m_d->previousPaintInformation,
m_d->previousTangent, newTangent);
m_d->previousTangent = newTangent;
}
m_d->olderPaintInformation = m_d->previousPaintInformation;
m_d->strokeTimeoutTimer.start(100);
}
else if (m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::NO_SMOOTHING) {
paintLine(m_d->previousPaintInformation, info);
}
if (m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::STABILIZER) {
m_d->stabilizedSampler.addEvent(info);
} else {
m_d->previousPaintInformation = info;
}
if(m_d->airbrushingTimer.isActive()) {
m_d->airbrushingTimer.start();
}
}
QPainterPath KisToolFreehandHelper::paintOpOutline(const QPointF &savedCursorPos,
const KoPointerEvent *event,
const KisPaintOpSettingsSP globalSettings,
KisPaintOpSettings::OutlineMode mode) const
{
KisPaintOpSettingsSP settings = globalSettings;
KisPaintInformation info = m_d->infoBuilder->hover(savedCursorPos, event);
info.setCanvasRotation(m_d->canvasRotation);
info.setCanvasHorizontalMirrorState( m_d->canvasMirroredH );
KisDistanceInformation distanceInfo(m_d->lastOutlinePos.pushThroughHistory(savedCursorPos), 0);
if (!m_d->painterInfos.isEmpty()) {
settings = m_d->resources->currentPaintOpPreset()->settings();
if (m_d->stabilizerDelayedPaintHelper.running() &&
m_d->stabilizerDelayedPaintHelper.hasLastPaintInformation()) {
info = m_d->stabilizerDelayedPaintHelper.lastPaintInformation();
} else {
info = m_d->previousPaintInformation;
}
/**
* When LoD mode is active it may happen that the helper has
* already started a stroke, but it painted noting, because
* all the work is being calculated by the scaled-down LodN
* stroke. So at first we try to fetch the data from the lodN
* stroke ("buddy") and then check if there is at least
* something has been painted with this distance information
* object.
*/
KisDistanceInformation *buddyDistance =
m_d->painterInfos.first()->buddyDragDistance();
if (buddyDistance) {
/**
* Tiny hack alert: here we fetch the distance information
* directly from the LodN stroke. Ideally, we should
* upscale its data, but here we just override it with our
* local copy of the coordinates.
*/
distanceInfo = *buddyDistance;
distanceInfo.overrideLastValues(m_d->lastOutlinePos.pushThroughHistory(savedCursorPos), 0);
} else if (m_d->painterInfos.first()->dragDistance->isStarted()) {
distanceInfo = *m_d->painterInfos.first()->dragDistance;
}
}
KisPaintInformation::DistanceInformationRegistrar registrar =
info.registerDistanceInformation(&distanceInfo);
QPainterPath outline = settings->brushOutline(info, mode);
if (m_d->resources &&
m_d->smoothingOptions->smoothingType() == KisSmoothingOptions::STABILIZER &&
m_d->smoothingOptions->useDelayDistance()) {
const qreal R = m_d->smoothingOptions->delayDistance() /
m_d->resources->effectiveZoom();
outline.addEllipse(info.pos(), R, R);
}
return outline;
}
