I'm making an app that is a venn diagram and I don't know how to do the first step. There are to ellipses and I want to color the shared area of two ellipses.
The green area is the shared area I meant.
You can use intersect mode on a combinedgeometry to find the parts overlap:
<Grid>
<Grid.Background>
<VisualBrush Stretch="None">
<VisualBrush.Visual>
<Canvas>
<Path Fill="Yellow">
<Path.Data>
<EllipseGeometry Center="150,50" RadiusX="75" RadiusY="75" />
</Path.Data>
</Path>
<Path Fill="Yellow">
<Path.Data>
<EllipseGeometry Center="50,50" RadiusX="75" RadiusY="75" />
</Path.Data>
</Path>
<Path Fill="Green">
<Path.Data>
<CombinedGeometry GeometryCombineMode="Intersect">
<CombinedGeometry.Geometry1>
<EllipseGeometry Center="150,50" RadiusX="75" RadiusY="75"/>
</CombinedGeometry.Geometry1>
<CombinedGeometry.Geometry2>
<EllipseGeometry Center="50,50" RadiusX="75" RadiusY="75"/>
</CombinedGeometry.Geometry2>
</CombinedGeometry>
</Path.Data>
</Path>
</Canvas>
</VisualBrush.Visual>
</VisualBrush>
</Grid.Background>
Position textblocks in the grid on top of the background shapes using rows and columns.
Or just put everything in a canvas rather than using a visualbrush.
Use Canvas.Left and Canvas.Top to position some textblocks on top of the ellipses.