WPF CornerRadius turn the Corners to the outside

Im trying to m开发者_如何学Pythonake my own ControlTemplate for an menu. Id like to turn the corners of some items to the outside. So that it look like the Word TabItems, i cant post an image im sry. But i hope you understand what i mean.

Is there a possibility to change the cornerradius like that? or are there other possibilitys?

regards Mark

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When I want to do something like that I often use a Grid with a Path drawn in the "corner" sections of the grid.

For example, a tab like the one in word could be drawn as a grid with 2x3 grid. The Top row would spam all 3 cells and contain an object with the top two corner radius set. The bottom row's middle cell would be the Text and the left and right ones would be a Path drawn the way you want it.