Snapping simplifies the positioning of crop areas, selection areas, and layer content (pixel or vector) by 'magnetizing' areas or content to other content or page elements (page edges, etc.).
Snapping for accurate crop and selection areas
To precisely create the above areas you can use snapping to position to previously placed guides or to the page edge itself.
Simply drag out your crop or selection area until its edge meets the positioned guide or page edge.
Snapping for vector lines, shapes, and text
Snapping causes images, brush strokes, lines, shapes, and selection areas to align to nearby grid lines, guides or spreads, or any combination of these. You can also snap to object bounding boxes, key points on shapes and to an object's geometry. Text can also snap to the baseline of other text (the first line only for text frames).
Snapping for vector layers
To help understand snapping behavior, colored dynamic guides and target nodes display when you snap to objects. The colors used are:
Red line: Object snaps to target horizontally.
Green line: Object snaps to target vertically.
Yellow node: Object snaps to shape's key points (often centers) or geometry.
Snapping candidates
Snapping candidates are layer contents which are available for you to snap to. You can set how candidates are created using the following settings:
Candidate List—limits the number of objects which are snapping candidates to the number you set (up to 18 candidates at any one time). Creating new layer content or hovering over existing content while dragging a selection marquee, designates the content as a snapping candidate. Only the active snapping candidates can be snapped to.
Immediate layers—limits the number of candidates to the objects on the current layer.
Immediate layers and children—limits the number of candidates to the objects on the current layer and any of the layer's subordinate child layers.
All layers—does not limit the number of snapping candidates in the document.
To activate/deactivate snapping:
Tap Snapping.
Snapping presets for vector layers
A powerful and comprehensive set of snapping options are available to you. To make snapping setup quick and easy, one of several snapping presets can be chosen which group recommended snapping options according to how you plan to work.
To select a snapping preset:
Open the Snapping menu (to the right of the Snapping button).
Select Snapping Options.
From the Preset menu, select a preset.
The remaining settings will change depending on the chosen preset. The options will be in effect immediately.
Customize any chosen snapping preset by changing any of its settings.
To customize a snapping preset:
Select a preset on which to base your new snapping options.
Enable/disable individual options to override the current preset's options.
The options will be in effect immediately.
Snapping options
Individual snapping options can be switched on or off to suit your needs, drawing style, and the project you are working on. The preset that you initially adopted will be customized in the process.
The following options are available:
Enable snapping—when enabled, objects will snap to specified criteria. This must be selected to change other options.
Preset—Select a preset which is a grouping of snapping options for specific ways of working.
Page layouts—for designs to be printed, where snapping to placed guides and spreads is important.
Page layouts with objects—as above but with additional object-to-object alignment.
Object creation—perfect for simple object-to-object alignment to bounding boxes and their midpoints, plus for aligning some shapes to key points. Key points are automatically added points on some objects, e.g. where a shape's corner is made rounded, key points are placed at the start and end of the rounded corner.
Curve drawing—the setup for non-geometric use (i.e., drawing with the Pen Tool).
UI design—for UI/web design for pixel accuracy when using snapping to fixed guides and grid.
Pixel work—for pixel-only brush work where vector-based object snapping is not needed.
Candidates—sets how candidates are used. Select from the pop-up menu.
Show snapping candidates—when enabled, highlights the active snapping candidates, i.e. objects that can be snapped to by prior selection. Candidates will display a purple outline.
Max Candidates—limits the number of active candidates when Candidate List is selected (see above). If you reach this limit, new candidates replace older candidates in chronological order.
Tolerance—controls the distance to an object before snapping occurs.
Force pixel alignment—snaps layers, objects and pixel selection areas to whole pixels when created, moved or modified. See Force Pixel Alignment.
Move by whole pixels—constrain the movement of layers, objects and pixel selection areas to whole pixels.
Snap to pixel selection bounds—when enabled, layer content can be snapped to the bounds of a pixel selection. For example, using the Flood Select Tool, a pixel selection drawn over image 'edges', which would otherwise not be snappable, will expose those edges for snapping.
Only snap to visible layers—when enabled, only visible layers are snapped to.
Snap to grid—when enabled, content snaps to a grid line. Not available when using Force Pixel Alignment.
Snap to guides—when enabled, content snaps to guides.
Snap to spread—when enabled, content snaps to the edge of the page.
Include spread midpoints—when enabled, content snaps to vertical or horizontal center of the page. This option is only available if the above option is selected.
Snap to margins—when enabled, content snaps to page margins (if switched on).
Include margin midpoints—when enabled, content snaps to vertical or horizontal center of the page margin. This option is only available if the above option is selected.
Snap to shape keypoints—when enabled, objects can be aligned to key points on shapes, e.g. the center of a rectangle or ellipse.
Snap to layer geometry—when enabled, objects can be snapped to layer vertices and not simply to the bounding box.
Snap to layer bounding boxes—when enabled, objects can be aligned based on its bounding box.
Include box midpoints—when enabled, objects snap to vertical or horizontal center of a target object. This option is only available if the above option is selected.
Snap to gaps and sizes—when enabled, arrows represent matched gaps between snapping candidates and matched horizontal and/or vertical sizes.