You can use Smart Snaps to center and size objects relative to each other or to their place on the page. The Smart Snaps appear as dotted lines on the page. Smart Snaps are on by default.
As you move an object left or right, you will see a dotted line appear vertically to indicate that the object is aligned to the center of the page.
As you move an object up or down, you will see a dotted line appear horizontally to indicate that the object is aligned to the midpoint of the page.
When you have more than one object on the page:
As you move an object, you will see dotted lines appear to indicate that the selected object is aligned to the edges or midpoint of other objects on the page.
Smart Snaps, when used with some irregular objects, such as multigons, may not appear to display proper alignment relative to the edges of other objects. This is because the alignment is being calculated mathematically.
When you have more than one object on the page:
As you resize an object, you will see dotted lines with arrows on either end appear. These indicate that the selected object is the same width or height as other objects on the page.
When you have more than two objects on the page:
As you move an object above or below other objects, you will see dotted lines with arrows on either end appear. These indicate when the objects are distributed equally, relative to each other.
You can control the types of objects that work with Smart Snaps.
With no objects selected, in the Grids and Guides section of the Properties bar, toggle the Smart Snaps checkbox.