#326 Fill draws in incorrect area for dot style case

[Morten Gundesen]

When using fill with style being dots the filled area can cover area not existing in the data. This seems to happen because the fill is done under the sampled points, which when zoomed is too low sampling and results in drawing between the dots instead of filling towards the actual data.

I have attached a pdf showing extra images of the case, also with the "expected result" from a potential code change.

In order to get the “expected result” I changed the code a bit so the filling is done according to a polygon rather than the sampled points in QwtPlotCurve::drawDots for the case doFill:

QPolygonF polyline = mapper.toPolygonF( xMap, yMap, data(), from, to );
fillCurve( painter, xMap, yMap, canvasRect, polyline);

instead of:
fillCurve( painter, xMap, yMap, canvasRect, points);

[Uwe Rathmann]

Fixed with Qwt 6.2