Check out the newest enhancements to the Sketch Environment.
You can now apply distance and 3-point angular dimensions to sketch line, arc, and part edge midpoints in Part, Assembly, and Drawing sketches.
For more information see To Work with Sketch Dimensions.
Edit and share sketch from sketch dimension
It is now possible to edit or share a sketch from a selected sketch dimension in parts and assemblies. After you select a dimension, the Edit Sketch option is available in the content menu for parts and assemblies, the Share Sketch option is available for parts only. Following 2D sketch dimensions are supported: offset dimension, two points distance dimension, tangent distance dimension, two lines angle dimension, three points angle dimension, diameter dimension, radius dimension.