Adobe illustrator 10 Manuale Utente
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Adobe Illustrator Help
Preparing Graphics for the Web
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To understand how Illustrator divides objects into pixels, open a file that contains vector
objects, choose View > Pixel Preview, and magnify the artwork so that you can see its
individual pixels. The placement of pixels is determined by an invisible grid that divides
the artboard into 1 point (1/72 inch) increments. If you move, add, or transform an object,
you’ll notice that the object snaps to the pixel grid. As a result, any anti-aliasing along the
“snapped” edges of the object (usually the left and top edges) disappears. Now deselect
the View > Snap to Pixel command, and move the object. This time, you’ll be able to
position the object between the pixel grid. Notice how this affects the anti-aliasing of the
object. As you can see, making very minor adjustments can affect how the object is
rasterized.
objects, choose View > Pixel Preview, and magnify the artwork so that you can see its
individual pixels. The placement of pixels is determined by an invisible grid that divides
the artboard into 1 point (1/72 inch) increments. If you move, add, or transform an object,
you’ll notice that the object snaps to the pixel grid. As a result, any anti-aliasing along the
“snapped” edges of the object (usually the left and top edges) disappears. Now deselect
the View > Snap to Pixel command, and move the object. This time, you’ll be able to
position the object between the pixel grid. Notice how this affects the anti-aliasing of the
object. As you can see, making very minor adjustments can affect how the object is
rasterized.
Vector preview and Pixel Preview
Important: The pixel grid is sensitive to the origin (0,0) of the ruler. Moving the origin of
the ruler will change how Illustrator rasterizes artwork.
the ruler will change how Illustrator rasterizes artwork.
To view artwork in pixel preview mode:
Choose View > Pixel Preview.
To disable or enable snapping in pixel preview mode:
Choose View > Snap to Pixel.
Note: By default, the Snap to Pixel command is enabled when you enter pixel preview
mode. You must deselect the Snap to Pixel command if you want to position objects
between the pixel grid.
mode. You must deselect the Snap to Pixel command if you want to position objects
between the pixel grid.
Dividing artwork into slices
Web pages can contain many elements—HTML text, bitmap images, and vector graphics,
to name a few. In Illustrator, you use slices to define the different Web elements in your
artwork. For example, if your artwork contains a bitmap image that needs to be optimized
in JPEG format, while the rest of the image is better optimized in GIF format, you can
isolate the bitmap image using a slice. When you save the artwork as a Web page, you can
choose to save each slice as an independent file with its own format, settings, and color
palette.
to name a few. In Illustrator, you use slices to define the different Web elements in your
artwork. For example, if your artwork contains a bitmap image that needs to be optimized
in JPEG format, while the rest of the image is better optimized in GIF format, you can
isolate the bitmap image using a slice. When you save the artwork as a Web page, you can
choose to save each slice as an independent file with its own format, settings, and color
palette.
Creating slices
There are several ways to create slices in Illustrator:
•
Use the Object > Slice > Make command when you want the slice dimensions to match
the boundary of an element in your artwork. If you move or modify the element, the
slice area automatically adjusts to encompass the new artwork. Also use this command
slice area automatically adjusts to encompass the new artwork. Also use this command