Drawing Snap Modes

This Tech Tip highlights the various snap modes.

Snap Modes
Snap modes can be accessed via the snaps toolbar


or via Tools › Jumps

Snap Modes can be used to select a particular Snap Mode you want to draw with. Snap Modes cause the cursor to behave in a particular way each time you press [Enter] or click. All of the Snap Modes except Freehand cause the cursor to do two things:
  1. To snap onto a specific point. For example, if you are in Grid Mode, the cursor will snap onto the nearest grid point when you press [Enter] or click.
  2. To accept the point that is snapped onto.
Freehand Mode is different from the other modes. Unlike them, it does not cause the cursor to snap onto a particular point when [Enter] is pressed or when you click. It merely accepts the point on which the cursor is currently located. To accept a specific point accurately while using Freehand Mode, move to that point first using, for example, the Arrow Keys or one of the Jumps, and then accept the point by pressing [Enter] or clicking.

Freehand Mode is the best mode to use for some functions. For example, if you use another mode for the Fillet function in the Modify Menu, the fillet may turn “inside-out”. Similarly, if you are using a function like Stretch in the Modify Menu, this function may appear not to be working unless you are in Freehand Mode. This is because the cursor may keep jumping back to the nearest point, usually the point you are trying to stretch! So if an inexplicable happening occurs, check your Snap Mode.

There are two differences between Snap Modes and Jumps:
  1. Snap Modes affect the cursor each time you press [Enter] or click. Jumps cause a “one-off” movement of the cursor, i.e. each time you want to perform a jump you have to select the jump.
  2. Snap Modes both move the cursor onto a point and accept that point. Jumps merely move the cursor. To accept a point after you have Jumped to it, you must press [Enter] or click.
The following snap modes are available:

Freehand:
You can enter the Freehand Mode, by clicking on the Freehand Icon on the Snaps Toolbar


or by pressing the [SHIFT] and F keys on your keyboard at the same time.

When you press [Enter] or click in Freehand Mode, the point that the cursor is located on is accepted, for example as the first point of a line.

Grab All:
You can enter the Grab All Snap Mode by clicking on the Graball Icon on the Snaps Toolbar


or by pressing the [SHIFT] and A keys on your keyboard at the same time.

When [Enter] is pressed or when you click when you are in Grab All Mode, the cursor will automatically snap onto the closest point, intersection or grid point enclosed within the cursor box. Grab All searches within the box in the following order:
  1. If a point (e.g. a point, the end of a line, the end of an arc, an arc or circle centre) is found within the box, take the nearest one.
  2. If a geometry intersection is found in the box, take the nearest one.
  3. If any other intersection is found in the box, take the nearest one.
  4. If any grid point is found within the box, take the nearest one.
If none of the above are found, the Grab All Mode will behave in the same way as the Freehand Mode.

NOTE: Unless you need to snap onto points, intersections and grid points, the Freehand Mode is a more efficient mode than the Grab All Mode on a large drawing because of the searches that the Grab All Mode must carry out.

Point:
You can enter the Point Snap Mode by clicking on the Point Snap Icon on the Snaps Toolbar


or by pressing the [SHIFT] and J keys on your keyboard at the same time.

When you draw in this Mode, the cursor will snap onto the nearest point when you press [Enter] or click. This may be a point drawn with the Point function in the Draw Menu, the end of a line or arc, an arc or circle centre point, the label origin of an item of text, the label origin of an item of dimension text or an arrow end point.

Perpendicular:
You can enter the Per Snap Mode by clicking on the Perp Snap Icon on the Snaps Toolbar


or by pressing the [SHIFT] and P keys on your keyboard at the same time.

The Perp Snap Mode snaps the end of a line to another line or arc so that they are perpendicular to one another.

The Perp Snap only works when you are drawing lines, including polylines and geometry Point-Point lines.

Grid:
You can enter the Grid Snap Mode by clicking on the Grid Snap Icon on the Snaps Toolbar


or by pressing the [SHIFT] and G keys on your keyboard at the same time.

When you draw in this Mode, the cursor will snap onto the nearest grid point when you press [Enter] or click. If no grid has been drawn, Grid Mode acts like the Freehand Mode (see Grid in the Tools Menu).

Geom Intersection:
You can enter the Geom Intersection Snap Mode by clicking on the Geometry Intersection Snap Icon on the Snaps Toolbar


or by pressing the [SHIFT] and I keys on your keyboard at the same time.

When you press [Enter] or click when you are in Geom Intersection Mode, the cursor will automatically snap onto the closest intersection or tangency point between geometry lines and circles. If no geometry has been drawn, the Geom Intersection Mode acts like the Freehand Mode.

Intersection:
You can enter the Intersection Snap Mode by clicking on the Intersection Snap Icon in the Snaps Toolbar


or by pressing the [SHIFT] and Z keys on your keyboard at the same time.

When you press [Enter] or click in Intersection Mode, the cursor will snap to the nearest intersection. This intersection can be any combination of lines, arcs and geometry lines and circles.

Circle Centre:
You can enter the Circle Centre snap mode by clicking on the Circle Centre Snap Icon on the Snaps Toolbar


or by pressing the [SHIFT] and E keys on your keyboard at the same time.

When you draw in this mode, the cursor will snap onto the nearest arc or circle centre when you press [Enter] or click.

This mode will not snap to the centres of Geometry circles. Use the Geom Intersection Mode for this.

Nearest Line/Arc:
You can enter the Nearest Line/Arc Snap Mode by clicking on the Nearest Element Icon in the Snaps Toolbar


or by pressing the [SHIFT] and N keys on your keyboard at the same time.

When you draw in this mode, the cursor will snap onto the nearest line or arc when you press [Enter] or click. This line or arc can be solid or geometry.

Tangent:
You can enter the Tangent Snap Mode by clicking on the Tangent Snap Icon on the Snaps Toolbar


or by pressing the [CTRL] and T keys on your keyboard at the same time.

The Tangent Snap Mode snaps a line or arc to another line or arc so that they are tangential to one another.

The Tangent snap only works when you are drawing lines or arcs. This includes polylines and the Point-Point and Circle commands in the Geometry Menu.

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