Let us explore how Visio handles curves.
This is a normal rectangle.
You can add rounded corners by selecting the Format Shape Dialog. From the Home tab chose Line from the Shape Styles section, then choose Line Options from the Line dropdown. That will bring u the Format Shape dialog.
Near the bottom is the Rounding size value.
You can also use one of the Rounding presets.
You will notice that the Geometry section is unchanged, but the Line Format section has a non zero value for Rounding.
So, what if you want only the top corners rounded?
Create a line where you want the shape to break and use the Fragment Operation from the Developer tab. You will see that the top section’s Geometry section has changed and Rounding is set to 0.
You should note, that now, if you stretch the shape vertically, the curves distort. That is because the curve is now based on the Height and Width of the shape.
You could simplify the shape by changing the EllipticalArcTo rows to ArcTo rows. ArcTo rows are not created automatically, you have to do a Change Row Type in the ShapeSheet.
The EllipticalArc row uses the previous row as the starting point and X, Y as the end point. A, B is a point on the curve. C is the angle of an arc’s major axis relative to the x -axis of its parent. D is the ratio of an arc’s major axis to its minor axis. For a circular the value C is0 and D is 1. With ArcTo, it is simpler, it just uses the distance from the midpoint of a cord to the midpoint on the curve.
I hope you find this useful.
John… Visio MVP in x-aisle