void TransferFunctionAlphaWidget::paintOpacityGraph(QPainter& painter)
{
QPen pointPen, pointLinePen;
pointPen.setColor(QColor(0, 0, 150));
pointLinePen.setColor(QColor(150, 100, 100));
// Go through each point and draw squares and lines
IntIntMap opacityMap = mImageTF->getOpacityMap();
QPoint lastScreenPoint;
this->mPointRects.clear();
for (IntIntMap::iterator opPoint = opacityMap.begin();
opPoint != opacityMap.end();
++opPoint)
{
// Get the screen (plot) position of this point
AlphaPoint pt(opPoint->first, opPoint->second);
QPoint screenPoint = this->alpha2screen(pt);
// draw line from left edge to first point:
if (opPoint==opacityMap.begin())
{
lastScreenPoint = QPoint(mPlotArea.left(), screenPoint.y());
}
// Draw line from previous point
painter.setPen(pointLinePen);
painter.drawLine(lastScreenPoint, screenPoint);
// Draw the rectangle
QRect pointRect(screenPoint.x() - mBorder, screenPoint.y() - mBorder,
mBorder*2, mBorder*2);
if (opPoint->first==mSelectedAlphaPoint.position)
{
pointPen.setWidth(2);
painter.setPen(pointPen);
}
else
{
pointPen.setWidth(1);
painter.setPen(pointPen);
}
painter.drawRect(pointRect);
this->mPointRects[opPoint->first] = pointRect;
// Store the point
lastScreenPoint = screenPoint;
}
// draw a line from the last point to the right end
QPoint screenPoint(mPlotArea.right(), lastScreenPoint.y());
painter.setPen(pointLinePen);
painter.drawLine(lastScreenPoint, screenPoint);
}
std::pair<int,int> TransferFunctionAlphaWidget::findAllowedMoveRangeAroundAlphaPoint(int selectedPointIntensity)
{
// constrain new point intensity between the two neigbours
IntIntMap opacityMap = mImageTF->getOpacityMap();
IntIntMap::iterator pointIterator = opacityMap.find(selectedPointIntensity);
std::pair<int,int> range(mImage->getMin(), mImage->getMax());
if (pointIterator!=opacityMap.begin())
{
IntIntMap::iterator prevPointIterator = pointIterator;
--prevPointIterator;
range.first = std::max(range.first, prevPointIterator->first + 1);
}
IntIntMap::iterator nextPointIterator = pointIterator;
++nextPointIterator;
if (nextPointIterator!=opacityMap.end())
{
range.second = std::min(range.second, nextPointIterator->first - 1);
}
return range;
}