Adobe 23101764 Scripting Guide - Page 61

Photoshop CS Scripting Guide

57

Scripting Photoshop

Working with units

3

The following example shows how to create 2 layers and then rename the

fi

rst one in

JavaScript.

// set ruler units and create new document

originalRulerUnits = app.preferences.rulerUnits

app.preferences.rulerUnits = Units.INCHES;

app.documents.add(4,4,72,"My New Document");

docRef = app.activeDocument;

layer1Ref = docRef.artLayers.add();

layer2Ref = docRef.artLayers.add();

layer1Ref.name = "This layer was first";

// restore unit setting

app.preferences.rulerUnits = originalRulerUnits;

3.6 Working with units

Photoshop provides two rulers for use when working on a document — a graphics ruler used

for most graphical layout measurements and a type ruler which is active when using the type

tool. The unit types for these two rulers are set using the

ruler units

(RulerUnits/rulerUnits)

and

type units (TypeUnits/typeUnits)

, respectively.

These settings correspond to those found in the Photoshop preference dialog under

“Edit >Preferences > Units & Rulers.”

The graphics ruler is used for most operations on a document where height, width, or position

are speci

fi

ed. The type ruler is used when operating on text items, such as when setting leading

or indent values. By changing the settings for each ruler you can work with documents in the

measurement system that make the most sense for the project at hand.

3.6.1

Unit values

Photoshop uses unit values for certain properties and parameters. Scripting comments

concerning Photoshop objects and properties note where unit values are used.

Because of scripting language differences, the way you provide a unit value in a script depends

on the language you are using. All languages support plain numbers for unit values. These

values are treated as being of the type currently speci

fi

ed for the appropriate ruler.

For example, if the ruler units are currently set to inches and the following Visual Basic

statement is executed:

docRef.ResizeImage 3,3

the document's image is resized to 3 inches by 3 inches. If the ruler units were set to pixels, the

image would be 3 pixels by 3 pixels, which is probably not what was intended. To ensure that

your scripts produce the expected results you should check and set the ruler units to the type

Section	Page
Photoshop CS Scripting Guide	1
Table of contents	3
Introduction	5
1.1 About this manual	5
1.1.1 Conventions in this guide	5
1.2 What is scripting?	6
1.3 Why use scripting?	7
1.4 What about actions?	7
1.5 System requirements	8
1.5.1 Mac	8
1.5.2 Windows	8
1.6 JavaScript	9
1.7 Choosing a scripting language	9
1.8 Legacy COM scripting	10
1.9 New Features	10
1.10 What’s Next	11
Scripting basics	12
2.1 Documents as objects	12
2.2 Object model concepts	12
2.2.1 Object classes	12
2.2.2 Object inheritance	13
2.2.3 Object elements or collections	13
2.2.4 Object reference	13
2.3 Object Model	14
2.3.1 Additional Containment Classes	16
2.3.2 Hello World Sample Scripts	18
2.4 Documenting scripts	21
2.5 Values	22
2.6 Variables	24
2.6.1 Assigning values to variables	24
2.6.2 Using variables to store references	25
2.6.3 Naming variables	25
2.7 Operators	26
2.8 Commands and methods	26
2.8.1 Conditional statements	27
2.8.2 Control structures	28
2.9 Handlers, subroutines and functions	29
2.10 Debugging and Error Handling	30
2.10.1 AppleScript debugging	31
2.10.2 Visual Basic debugging	32
2.10.3 JavaScript Debugging	33
2.10.4 Error handling	33
2.11 What’s Next	34
Scripting Photoshop	35
3.1 Photoshop scripting guidelines	35
3.2 Viewing Photoshop objects, commands and methods	35
3.2.1 Viewing Photoshop’s AppleScript dictionary	36
3.2.2 Viewing Photoshop’s type library (VB)	37
3.2.3 Viewing the JavaScript Environment	37
3.3 Your first Photoshop script	39
3.3.1 AppleScript	39
3.3.2 Visual Basic	40
3.3.3 VBScript	42
3.3.4 JavaScript	43
3.4 Advanced Scripting	45
3.4.1 Advanced JavaScript	45
3.4.2 Advanced Visual Basic	50
3.4.3 Advanced AppleScript	54
3.5 Object references	59
3.5.1 AppleScript	59
3.5.2 Visual Basic and JavaScript	60
3.6 Working with units	61
3.6.1 Unit values	61
3.6.2 Unit value useage	64
3.6.3 Changing ruler and type units	65
3.7 Executing JavaScripts from AS or VB	66
3.7.1 Passing arguments to JavaScript	67
3.7.2 Executing one-line JavaScripts	68
3.8 The Application object	68
3.9 Document object	72
3.9.1 Saving documents and save options	72
3.9.2 Document information	74
3.9.3 Document manipulation	75
3.10 Layer objects	76
3.10.1 Setting the Active layer	79
3.10.2 Layer sets	79
3.10.3 Linking layers	80
3.10.4 Applying styles to layers	81
3.10.5 Rotating layers	81
3.11 Text item object	81
3.11.1 Setting the contents of the text item	83
3.11.2 Setting text stroke colors	84
3.11.3 Setting fonts	84
3.11.4 Warping text	85
3.12 Selections	85
3.12.1 Defining selections	86
3.12.2 Stroking the selection border	88
3.12.3 Inverting selections	88
3.12.4 Expand, contract and feather selections	88
3.12.5 Filling a selection	90
3.12.6 Rotating selections	91
3.12.7 Loading and storing selections	91
3.13 Working with Filters	92
3.13.1 Selecting channel(s) to filter	92
3.13.2 Other filters	93
3.14 Channel object	93
3.14.1 Channel types	93
3.14.2 Setting the active channel	94
3.14.3 Creating new channels	94
3.15 Color objects	95
3.15.1 Setting a Color	95
3.15.2 Getting and converting colors	97
3.15.3 Comparing Colors	98
3.15.4 Getting a Web Safe Color	98
3.16 History object	98
3.16.1 Filling a selection with a history state	99
3.17 Clipboard interaction	100
3.17.1 Copy	100
3.17.2 Copy merged	100
3.17.3 Cut	101
3.17.4 Paste	101
3.17.5 Paste into command	102

Adobe 23101764 Scripting Guide - Page 61

Working with units

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