3ds Max 2012 Bible - Kelly L. Murdock [107]
Cross-Reference
For more information on NURBS, see Bonus Chapter 5 on the CD, “Working with NURBS.” •
After snap points have been defined, the Snap buttons on the main toolbar activate the Snap feature, or you can press the S key. The first Snaps button consists of a flyout with three buttons: 3D Snap toggle, 2.5D Snap toggle, and 2D Snap toggle. The 2D Snap toggle button limits all snaps to the active construction grid. The 2.5D Snap toggle button snaps to points on the construction grid as well as projected points from objects in the scene. The 3D Snap toggle button can snap to any points in 3D space.
FIGURE 7.18
The Snaps panel includes many different points to snap to depending on the object type.
When snapping is enabled, a small circle appears at the center of the pivot point. This circle is a visual reminder that snapping is enabled. When you move an object while snapping is enabled, you can either drag the small circle to move the object freely between snapping points or drag the Move tool's controls to constraint the object's movement.
As you drag an object, the starting position is marked and a line is drawn between this starting point and the destination point. Available snapping points are marked with a set of cross-hairs. If you release the object, it snaps to the highlighted set of cross-hairs. The line connecting the starting and end points and the snapping point cross-hairs are colored green when the object is over an available snapping point and yellow when not.
In addition to the small circle icon and the Move tool controls, you can move the mouse over the object and any available snapping points on the object are highlighted. For example, if the Vertex option in the Grid and Snap Settings dialog box is enabled, moving the mouse over one of a box object's corners highlights the corner with a set of yellow cross-hairs. Dragging while a vertex's cross-hair is highlighted lets you snap the selected corner to another position.
Tutorial: Creating a 2D outline of an object
The 2.5D snap can be confusing. It limits snapping to the active construction grid, but within the active grid, it can snap to 3D points that are projected onto the active grid. You can create a 2D representation of a 3D object by snapping to the vertices of the suspended object.
To create a 2D outline of a cylinder object, follow these steps:
1. Select the Create⇒Standard Primitives⇒Cylinder menu to create a simple cylinder object.
2. Select and rotate the cylinder so it is suspended and rotated at an angle above the construction grid.
3. Click and hold the Snap toggle button, and select the 2.5D Snap flyout option. Then right-click the Snap toggle and select only the Vertex option in the Snaps panel. Then close the Grid and Snap Settings dialog box.
4. Choose the Create⇒Shapes⇒Line menu and create a line in the Top viewport by snapping to the points that make the outline of the cylinder.
Figure 7.19 shows the projected outline.
FIGURE 7.19
The 2.5D snap feature snaps to vertices of 3D objects projected onto the active grid.
Tip
Right-clicking the Snap toggle opens the Grid and Snap Settings dialog box, except for the Spinner Snap toggle, which opens the Preference Settings dialog box. •
These Snap buttons control the snapping for translations. To the right are two other buttons: Angle Snap toggle and Percent Snap. These buttons control the snapping of rotations and scalings.
Note
The keyboard shortcut for turning the Snap feature on and off is the S key. •
Setting snap points
The Snaps tab in the Grid and Snap Settings dialog box has many points that can be snapped to in two categories: Standard and NURBS. The Standard snap points (previously shown in Figure 7.18) include the following:
• Grid Points: Snaps to the Grid intersection points
• Grid Lines: Snaps only to positions located on the Grid lines
• Pivot: Snaps to