I have a quite difficult issue: I need to simplify polygons, but without "trimming" them - no parts of polygon can be lost; furthermore, all holes in polygons should be filled (but this last is less important and can be done by hand). I presented an example of what I need - the brown polygon is original, and the red outline is desired extent.
There is a significant amount of similar questions on the StackExchange, but answers were not sufficient.
I use QGIS 2.18.3 and I made some trials using SimpliPy plugin - but results using tolerance: 10 are not so satisfactory. Second picture presents it: in some places work has been done well by the plugin, but some parts are excessively simplified. Also, there are parts that had not been simplified.
I wonder whether I should just try with SimpliPy settings and parameters - or should I look for another way (maybe GRASS / SAGA algorithms)