Drafting Aids
Drafting aids assist user input to create accurate shapes.
The appearance of the crosshair cursor changes when coordinates are required for user input. The blue rectangular "aperture" area is the range where object snaps are recognized. When it intersects with a shape, it displays the closest applicable snap point.
Object Snap
Acquires base points on shapes. The OSMODE system variable controls which object snap types are active. Use the [F3] key to toggle them on or off.
| Command Modifier | Name | Mark | Description | Bit Flag |
|---|---|---|---|---|
| END | Endpoint |  | Snaps to the endpoint of a shape. | 1 |
| MID | Midpoint |  | Snaps to the midpoint of a shape. | 2 |
| CEN | Center |  | Snaps to the center of a circle or arc. | 4 |
| NOD | Node |  | Snaps to the base point of a point object. | 8 |
| QUA | Quadrant |  | Snaps to a quadrant point of a circle or ellipse. | 16 |
| INT | Intersection |  | Snaps to the intersection of shapes. | 32 |
| INS | Insertion |  | Snaps to the insertion point of text or block references. | 64 |
| PER | Perpendicular |  | Snaps to a point perpendicular to the specified shape. | 128 |
| TAN | Tangent |  | Snaps to the tangent point on a circle or arc. | 256 |
| NEA | Nearest |  | Snaps to the nearest point on a shape within the pickbox. | 512 |
| NON | None | - | When object snap is off, 16384 is added to the value. | 16384 |
Ortho Mode
Restricts cursor movement to the horizontal and vertical directions relative to the current UCS. Toggle it with the ORTHOMODE command or the [F8] key.
| Positive X direction | Positive Y direction |
|---|---|
 |  |
Polar Tracking
Restricts cursor movement to specified angles. Toggle it with the POLARMODE command or the [F10] key.
| 30 Degrees | 60 Degrees |
|---|---|
 |  |