Adobe 65048332 Scripting Guide - Page 13

C

HAPTER

2: Photoshop Scripting Basics

Photoshop Object Model

13

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 36

.

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 46

.

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 42

.

History State class

The

History

State

class is a palette object that keeps track of changes made to a document. Each time

you apply a change to an image, the new state of that image is added to the palette. These states are

accessible from document object and can be used to reset the document to a previous state. A history

state can also be used to fill a selection. For more information on history objects, see

“Using history state

objects” on page 47

.

N

OTE

:

In AppleScript, if you create a document and then immediately try to get history state, Photoshop

returns an error. You must first activate Photoshop—make it the front-most application—before you can

access history states.

Document Info class

The

Document

Info

class stores metadata about a document. Metadata is any data that helps to describe

the content or characteristics of a file. For more information on document info, see

“Using the Document

Info object” on page 47

.

Section	Page
Adobe® Creative Suite® 5 Photoshop® Scripting Guide	2
Introduction	6
About this Manual	6
Conventions in this Guide	6
Photoshop Scripting Basics	8
Scripting Overview	8
Why use scripts instead of actions?	8
Scripting Support in Photoshop	9
JavaScript support	9
Executing other scripts	10
Startup scripts	10
Executing JavaScripts from AS or VBS	10
Photoshop Object Model	11
Containment hierarchy	11
Application and document classes	12
Layer classes	12
Layer Comp class	13
Channel class	13
Selection class	13
History State class	13
Document Info class	13
Path Item, Sub Path Item, and Path Point classes	14
Preferences class	14
Notifier class	14
Count Item class	14
Color Sampler class	14
Measurement Scale class	14
The containment hierarchy and the Photoshop user interface	14
Additional objects	16
Constants	16
Creating a sample Hello World script	17
Creating and running an AppleScript	18
Creating and running a VBScript	19
Creating and running a JavaScript	19
Scripting Photoshop	21
Viewing Photoshop Objects, Commands, and Methods	21
Viewing Photoshop’s AppleScript dictionary	21
Viewing Photoshop’s type library (VBS)	22
Targeting and Referencing the Application Object	22
Creating New Objects in a Script	23
Setting the Active Object	25
Setting the active document	26
Setting the active layer	27
Setting the active channels	28
Opening a Document	28
Opening a file with default file format	28
Specifying file formats to open	29
Saving a Document	31
Setting Application Preferences	32
Allowing or Preventing Dialogs	33
Working with the Photoshop Object Model	33
Using the Application object	34
Using the Document object	34
Manipulating a document object	35
Working with layer objects	36
Creating an ArtLayer object	37
Creating a Layer Set object	38
Referencing ArtLayer objects	38
Working with Layer Set objects	39
Linking layer objects	40
Applying styles to layers	40
Using the Text Item object	41
Determining a layer’s kind	41
Adding and manipulating text in a Text Item object	42
Working with Selection objects	42
Creating and defining a selection	43
Stroking the selection border	44
Inverting selections	44
Expanding, contracting, and feathering selections	44
Filling a selection	45
Loading and storing selections	45
Working with Channel objects	46
Changing channel types	46
Using the Document Info object	47
Using history state objects	47
Using Notifier objects	48
Using the PathItem object	49
Working with color objects	51
Solid color classes	52
Using hex values for RGB color	52
Getting and converting colors	52
Comparing colors	53
Getting a Web-safe color	53
Working with Filters	53
Other filters	54
Understanding Clipboard Interaction	54
Using the copy and paste commands	54
Using the copy merged command/method	55
Working with Units	56
Unit values	56
Special unit value types	56
AppleScript unit considerations	56
Using unit values in calculations	57
Unit value usage	57
Setting ruler and type units in a script	59
Sample Workflow Automation JavaScripts	60
Advanced Scripting	60
Working with document preferences	61
Applying color to a text item	64
Applying a wave filter	66
Defining the area of a selection object	67
Applying a MotionBlur filter	71
Action Manager	73
The ScriptListener Plug-In	73
Installing ScriptListener	73
Action Manager Scripting Objects	74
Recording a Script using ScriptListener	74
Using the Action Manager from JavaScript	75
Using the Action Manager from a VBS Script	76
Running JavaScript-based Action Manager code from VBScript	79
Running JavaScript-based Action Manager code from AppleScript	80
Using ScriptListener to find event IDs and class IDs	81

Adobe 65048332 Scripting Guide - Page 13

Layer Comp class, Channel class, Selection class, History State class, Document Info class

Page 13 highlights