Bug report #15419
Geometry displays incorrectly
|Affected QGIS version:||2.16.1||Regression?:||No|
|Operating System:||Easy fix?:||No|
|Pull Request or Patch supplied:||No||Resolution:||fixed/implemented|
|Crashes QGIS or corrupts data:||No||Copied to github as #:||23347|
QGIS 2.12, 2.16.
Some of geometry (Polygons) such as from shapefiles displayed incorrectly. I am talking about polygons with rings inside. This polygons display as filled polygons without rings.
In most cases, if you do not check it in advance, you can miss the fact that inside of those rings there might be an object. Also you can miss fact that inside of polygon there might not be some area. If I use "Geometry checker" or "Topology checker" I can see that some geometries are incorrect. But for large projects doing this on a regular basis is extremely unconfortable.
In other GIS when I add shapefile with incorrect geometries (from QGIS point of view) to project it displays all objects correctly or I can see what needs to be.
In attachments demonstrate situation when inside polygon deleted ring and formed other polygon.
QgsSymbol::renderFeature(): render larger parts of multipolygon first
When drawing an invalid multipolygon, that has a part inside another one,
there is a chance we draw first the smaller part and then the larger part,
making it invisible.
Change the drawing order to start with larger parts.