Photoshop CS3
Adobe Photoshop CS3 Scripting Guide Photoshop CS3 Scripting Basics 11
The Application class is the root of the Photoshop CS3 object model hierarchy. Scripts must target the
appropriate application in order to run correctly. See ‘Targeting and Referencing the Application Object’
on page 20.
The
Document class is used to make modifications to the document image. By using the Document object
you can crop, rotate or flip the canvas, resize the image or canvas, and trim the image. You could also use
the
Document object to get the active layer, then, save the current document, and copy and paste within
the active document or between different documents. For more information on using document objects,
see ‘Creating New Objects in a Script’ on page 21
and ‘Using the Document Object’ on page 32.
Layer Classes
Photoshop has two types of layers: an Art Layer that can contain image contents and a Layer Set that
can contain zero or more art layers.
An
Art Layer is a layer class within a document that allows you to work on one element of an image
without disturbing the others. Images are typically composed of multiple layers, defined by a
Layer Set.
You can change the composition of an image by changing the order and attributes of the layers that
comprise it.
A
Text Item is a particular type of art layer that allows you to add type to an image. In Photoshop, a Text
Item
item is implemented as a property of the art layer. For more information on text items, see ‘Using the
Text Item Object’ on page 39.
A Layer Set is a class that comprises multiple layers. Think of it as a folder on your desktop. Since folders
can contain other folders, a layer set is recursive. That is, one layer set may call another layer set in the
Object Model hierarchy.
For more information on layers, see ‘Working with Layer Objects’ on page 34
.
Layer Comp Class
The Layer Comp class allows you to create, manage, and view multiple versions of a layout within a single
document.
Channel Class
The Channel class is used to store pixel information about an image’s color. Image color determines the
number of channels available. An RGB image, for example, has four default channels: one for each primary
color and one for editing the entire image. You could have the red channel active in order to manipulate
just the red pixels in the image, or you could choose to manipulate all the channels at once.
These kinds of channels are related to the document mode and are called component channels. In addition
to the component channels, Photoshop lets you to create additional channels. You can create a spot color
channel, a masked area channel, and a selected area channel.
Using the commands or methods of a
Channel object, you can create, delete and duplicate channels. You
can also retrieve a channel's histogram, change its kind or change the current channel selection.
For more information on channels, see ‘Working with Channel Objects’ on page 45
.
Selection Class
The Selection class is used to specify an area of pixels in the active document (or in a selected layer of the
active document) that you want to work with. For more information on selections, see ‘Working with
Selection Objects’ on page 41.
