Sketching the foundations of 3D bodies requires accuracy. To be able to sketch with correct dimensions on the fly, use snapping guidelines as a visual aid.
In general, you can snap your sketch to any line, arc, intersection. Select to access the settings for snapping.
These are the switches:
- Snap to grid
If you turn this on, it forces your sketches to snap to a specific grid point. You’ll see a purple line like in this GIF, to guide your line. If you turn it off, then you can draw a line anywhere on the grid, without your line’s end point snapping to a grid point.
If you turn this on, you can see purple lines that are guidelines to ensure you’re moving your sketch lines horizontally or vertically or to a specific point (either along or at the end of a line, the center of an existing face or a sketch). It will also show you an extension of any existing lines, so you can make sure your sketch lines are equal, horizontal, vertical, symmetrical, tangent, perpendicular, or parallel, in relation to lines, points, and centers.
- Guides on selection
If you turn this on, a purple line will appear along your existing line when you select the line so you can see where the line would extend. If you draw an arc, then you’ll see two purple lines that represent the diameter of the circle when you select the arc. If you have multiple arcs, you can see purple lines that connect one arc’s center to the other arc’s center and points.
If you turn this on, the midpoint of a line will appear when you try to snap to it, or when you create a new shape.
- Sketch/Face center
If you turn this on, the center point of a closed sketch or a face will appear as a purple point.
- Snapping hint
If you turn this on, you will see labels for snapping points, such as “end point,” “midpoint,” “sketch center.”
When you snap to a point on a line or arc, the snapping is indicated by a purple circle. When you snap to edges, that’s indicated by a purple cube.
You can only use snapping for connected sketches, but if you hover over another sketch, you can create a snapping relation with that, too.
Different type of snaps:
- Line extensions
Select a line. You can immediately snap to its extension, too.
Guidelines can indicate the local minimums and maximums of your splines, helping you snap in relation to where your splines are.
- X-Y-Z axes
You can snap to the X, Y, and Z axes. When you snap to them, you can see the axis name.
You can snap to midpoints, or the middle of a line.
- Sketch and face centers
If you create simple geometry—rectangles, circles, and triangles—the center is automatically created, and you can snap to them.
This tutorial dives into the details: