Form: Snap Options
Toolbar button:
The Draw menu > Snap Options command is intended to help ensure that column, beam/line, slab, wall, tendon and design strip objects are located "precisely" during drawing or editing. When a snap location is found close to the mouse pointer, the mouse pointer changes to a square, triangle, hourglass or other cursor depending on the type of snap, and the object being drawn will snap to the identified item.
Click the Draw menu > Snap Options command or hold down the Shift key on the keyboard and click on the associated Snap button, 
, to access the Snap Options form, which offers the following options:
Snap To. Check an option to turn it on; uncheck it to turn it off. Any combination of options can be used for simultaneous action. In an active window, if more than one snap option has been activated and the mouse pointer is located such that it is within the screen “snap to” tolerance of multiple snap features, switch to a different snap by pressing the “N” key (N for Next) on the keyboard. Continue to press the “N” key until the mouse snaps to the desired item.
Points - Snaps to points.
Line Ends and Midpoints - Snaps to the midpoints and ends of existing line objects and to the midpoints and ends of edges of area objects. Note that the end of an edge of an area object is a corner point of the area object.
Grid - Snaps to grid line intersections.
Lines - Snaps to line objects.
Edges - Snaps to edges of area objects.
Perpendicular Projections - First draw the first point for a line or area object. Then, with this snap feature active, place the mouse pointer over another line object or edge of an area object and left click. A line object or edge of an area object will then be drawn from the first point perpendicular to the line object or edge of an area object that the mouse pointer was over when the second point was clicked.
Intersections - Snaps to the intersections of line objects with other line objects and with the edges of area objects. It does not snap to the intersection of the edge of one area object with the edge of another area object.
Fine Grid - Finds and snaps to the intersections of the fine grids in a Plan View.
Extensions - Finds and snaps to extensions of line objects and edges of area objects in a plan view.
Parallels - Snaps lines and areas parallel to line objects and edges of area objects in a plan view. The line object or edge being used as a parallel guide for the object being drawn is highlighted.
Intelligent Snaps - Features a selective set of snap functions that are activated automatically when drawing a column or beam. When drawing a column or beam object, pass the mouse cursor over an existing column and the program snaps to imaginary lines passing through the column that are parallel to the X- and Y-axes, and the snaps are displayed at the increments specified in the Snap Increments area of the form. Move the cursor onto a beam or area edge, and the program will snap to these lines as well at displayed increments. This option greatly facilitates the drawing of columns and beams objects because it seeks out the snaps that are deemed most appropriate (i.e., it is intelligent based on the object type).
Snap Increments - Choose an option to have the program snap to specific lengths when drawing any object using lines (beams, area edges, walls, design strips, tendons, dimension lines)
(Imperial in Inches) Snap at length increments of - . Enter the increments in inch units separated by a semi-colon; any number of increments may be specified. When drawing the object, the cursor will snap to any length dimension that is divisible by one of the specified increments. The length is displayed while drawing.
(Metric in mm) Snap at length increments of - Enter the increments in mm units separated by a semi-colon; any number of increments may be specified. When drawing the object, the cursor will snap to any length dimension that is divisible by one of the specified increments. The length is displayed while drawing.
(Degree) Snap at angle increments of - Enter the angle in degrees; only one angle increment may be specified. When drawing the object, the cursor will snap to any angle that is divisible by the specified increment. The angle is displayed while drawing.
Settings
Plan Fine Grid Spacing - This is the spacing of invisible grid points that are used by the Fine Grid option. This item is entered in length units. The SAFE default for this item is 12 inches in English units or 0.3048 meter in metric units.
Plan Nudge Value - This is the distance that a nudged object moves after you have pressed the appropriate key on the keyboard. This item is entered in length units. The SAFE default for this item is 12 inches in English units or 0.3048 meter in metric units.
Screen Selection Tolerance - When clicking on an object to select it, your mouse pointer must be within this distance of the object to select it. This item is entered in pixels. The screen selection tolerance has no effect on selection by windowing. The default for this item is 3 pixels.
Screen Snap To Tolerance - When using the snap features, your mouse pointer must be within this distance of a snap location to snap to it. This item is entered in pixels. The default for this item is 12 pixels.
Drawing Scale - If this check box is checked, select a drawing scale from the drop down list. The drawing scale selected affects line widths and the coarseness of the background horizon grid, reflecting how objects would look if they were actually drawn at the chosen scale. The drawing scale is also used as the default scale setting when using the File menu > Print Graphics command. Click the button to add a drawing scale.
Move Draft Helper Controls with Mouse - If this check box is checked, the drafting control box will move with the mouse cursor. For example, if you are drawing a line, the L,theta edit box will move with the cursor rather than being anchored in the lower left-hand corner of the view.
User Coordinate System (UCS) - Input values into the three edit boxes (Origin X, Origin Y, Rotation Z) to create an alternate reference coordinate system. After it has been created, the UCS may be selected using the coordinate system drop-down list in the lower right-hand corner of the SAFE screen.
Unlike the Define menu > Coordinate System command, using the option on the Snap Options form does not create a named coordinate system with grids, but simply creates an alternate origin with X- and Y- axes. When in a drawing mode with the UCS active, lines will snap to inferred alignments that are parallel to the UCS axes. This option greatly facilitates the placement of objects that are skewed within the global coordinate system.
TIP: The User Coordinate System (UCS) may be moved using the Draw menu > Reshape Object command. With the UCS active, click the Draw menu > Reshape Object command and then click somewhere on the UX or UY axes. Grab either handle at the ends of the axes to rotate the UCS, or grab the handle at the UCS origin to move the coordinate system without rotating.
Note: The Snap ON/OFF button, 
, has two functions. First, clicking directly on this button will toggle on and off the snap options checked in the Snap to area of the Snap Options form. The snap options are active when the button is highlighted. Second, holding down the Shift key while clicking on this button will display the Snap Options form.