js Reference

Execute Javascript

js

Description

Exposes the Javascript language and some Max specific extensions. The js object can be instantiated with a javascript filename or with numerical arguments to specify the number of outlets and inlets respectively. The default number of outlets and inlets are both 1.

Examples

Two js objects instantiated with different arguments the Javascript code creates the objects with different numbers of outlets based on the arguments

Discussion

Note that this implementation does not include the traditional web browser specific extensions that are often associated with Javascript.

Arguments

filename [symbol]

Optional

Specifies the name of a text file to be used as the Javascript source. If no argument is specified, it will not initially have any Javascript associated with it. You can still open a text window and edit and save the Javascript source, but unless you recreate the object with the saved source filename as an argument, the file will not be used when a patch containing the js object is loaded.

inlets-outlets [list]

Optional

If no filename is present as an argument, the number of inlets and outlets is specified. If one int argument is present, the number of desired outlets is specified. If two int arguments are present, the first number specifies the number of outlets and the second number specifies the number of inlets.

jsarguments [list]

Optional

Following the optional filename or number of outlets and inlets, any symbols or numbers can be entered that will be assigned to the Javascript variable jsarguments. jsarguments[0] is the filename entered, and jsarguments[1] is the first typed-in argument following the filename. The Javascript expression jsarguments.length will be one more than the number of typed-in arguments

Attributes

parameter_enable [int]

Enables use of this object with Max for Live Parameters.

parameter_mappable [int] (default: 1)

When parameter_mappable is enabled, the object will be available for mapping to keyboard or MIDI input using the Max Mappings feature.

template [symbol] (default: none)

If no file is explictly loaded via an argument to the js object, the template file will be loaded into memory and evaluated, and can be used as the starting point for further development. The user will be prompted to save the template to a file when editing, or the external editor is opened.

Common Box Attributes

annotation [symbol]

Sets the text that will be displayed in the Clue window when the user moves the mouse over the object.

background [int] (default: 0)

Adds or removes the object from the patcher's background layer. background 1 adds the object to the background layer, background 0 removes it. Objects in the background layer are shown behind all objects in the default foreground layer.

color [4 floats]

Sets the color for the object box outline.

fontface [int]

Sets the type style used by the object. The options are:

plain
bold
italic
bold italic Possible values:

0 = 'regular'
1 = 'bold'
2 = 'italic'
3 = 'bold italic'

fontname [symbol]

Sets the object's font.

fontsize [float]

Sets the object's font size (in points). Possible values:

'8'
'9'
'10'
'11'
'12'
'13'
'14'
'16'
'18'
'20'
'24'
'30'
'36'
'48'
'64'
'72'

hidden [int] (default: 0)

Toggles whether an object is hidden when the patcher is locked.

hint [symbol]

Sets the text that will be displayed in as a pop-up hint when the user moves the mouse over the object in a locked patcher.

ignoreclick [int] (default: 0)

Toggles whether an object ignores mouse clicks in a locked patcher.

jspainterfile [symbol]

JS Painter File

patching_rect [4 floats] (default: 0. 0. 100. 0.)

Sets the position and size of the object in the patcher window.

position [2 floats]

g/s(set)

Sets the object's x and y position in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its size unchanged.

presentation [int] (default: 0)

Sets whether an object belongs to the patcher's presentation.

presentation_rect [4 floats] (default: 0. 0. 0. 0.)

Sets the x and y position and width and height of the object in the patcher's presentation, leaving its patching position unchanged.

rect [4 floats]

g/s(set)

Sets the x and y position and width and height of the object in both patching and presentation modes (if the object belongs to its patcher's presentation).

size [2 floats]

g/s(set)

Sets the object's width and height in both patching and presentation modes (if the object belongs to its patcher's presentation), leaving its position unchanged.

textcolor [4 floats]

Sets the color for the object's text in RGBA format.

textjustification [int]

Sets the justification for the object's text. Possible values:

0 = 'left'
1 = 'center'
2 = 'right'

varname [symbol]

Sets the patcher's scripting name, which can be used to address the object by name in pattr, scripting messages to thispatcher, and the js object.

Parameter Attributes

Order

Typeint

Sets the order of recall of this parameter. Lower numbers are recalled first. The order of recall of parameters with the same order number is undefined.

Parameter Mode Enable

Typeint

Parameter Mode Enable (not available from Parameters window)

Link to Scripting Name

Typeint

When checked, the Scripting Name is linked to the Long Name attribute.

Long Name

Typesymbol

The long name of the parameter. This name must be unique per patcher hierarchy.

Short Name

Typesymbol

Sets the short name for the object's visual display. The maximum length varies according to letter width, but is generally in a range of 5 to 7 characters.

Type

Typeint

Specifies the data type. The data types used in Max for Live are:

Float
Int
Enum (enumerated list)
Blob

Note: By convention, the Live application uses floating point numbers for its calculations; the native integer representation is limited to 256 values, with a default range of 0-255 (similar to the char data type used in Jitter). When working with Live UI objects whose integer values will exceed this range, the Type attribute should be set to Float, and the Unit Style attribute should be set to Int.

Range/Enum

Typelist

When used with an integer or floating point data type, this field is used to specify the minimum and maximum values of the parameter.
When used with an enumerated list (Enum) data type, this field contains a space-delimited list of the enumerated values (if list items contain a space or special characters, the name should be enclosed in double quotes).

Clip Modulation Mode

Typeint

Sets the Clip Modulation Mode used by the Live application. The modulation modes are:

None
Unipolar
Bipolar
Additive
Absolute

Clip Modulation Range

Typelist

This parameter is only used with the Absolute modulation mode. It specifies defines the range of values used.

Initial Enable

Typeint

When checked (set to 1), the UI object can store an initialization value. The value is set using the Initial attribute (see below).

Initial

Typelist

Sets the initial value to be stored and used when the Initial Enable attribute is checked.

Unit Style

Typeint

Sets the unit style to be used when displaying values. The unit style values are: Int: displays integer values
Float: displays floating point values
Time: displays time values in milliseconds (ms)
Hertz: displays frequency values (Hz/kHz).
deciBel: displays loudness (dB)
%: Percentage
Pan: displays Left and Right values
Semitones: displays steps (st)
MIDI: displays pitch corresponding to the MIDI note number
Custom: displays custom data type
Native: defaults to floating point values

Custom Units

Typesymbol

Sets the units to be used with the 'Custom' unit style (see "Unit Style", above). Custom unit strings may be simple symbols (e.g. "Harmonic(s)"), in which case the parameter's value will be displayed in its 'Native' display mode, followed by the symbol (e.g. "12 Harmonic(s)" for an Int-typed parameter or "12.54 Harmonic(s)" for a Float-typed parameter). For additional control over the numerical component displayed, a sprintf-style string may be used (e.g. "%0.2f Bogon(s)", which would display a value such as ".87 Bogons").

Exponent

Typefloat

When set to a value other than 1., the parameter's input and output values will be exponentially scaled according to the factor entered in this column.

Steps

Typeint

The number of steps available between the minimum and maximum values of a parameter. For instance, if the parameter has a range from 0.-64., with Steps set to 4, the user can only set the parameter to 0, 21.33, 42.66 and 64.

Parameter Visibility

Typeint

For automatable parameters (Int, Float, Enum), 'Stored Only' disables automation, although parameter values are stored in presets. 'Hidden' causes the parameter's value to be ignored when storing and recalling data. Non-automatable parameters (Blob) are 'Stored Only' by default, and can be set to 'Hidden', if desired.

Update Limit (ms)

Typeint

Speed limits values triggered by automation.

Defer Automation Output

Typeint

Defers values triggered by automation.

Messages

bang

Invokes the function named bang if defined.

int

Arguments

user-defined [int]
Invokes the function named msg_int if defined.

float

Arguments

user-defined [float]
Invokes the function named msg_float if defined.

list

Arguments

user-defined [list]
Performs the same as anything.

anything

Arguments

user-defined [list]
Invokes the function with the message name, assigning the message arguments to the arguments to the function. For example, if the object has a function named xyz defined, the message xyz 1 2 3 would invoke the xyz function with arguments 1 2 and 3.

autowatch

Arguments

flag [int]
The message autowatch, followed by a 1, turns on file watching for the Javascript source file. When file watching is on, the file is recompiled automatically when it is modified. This allows you to use an external editor for your Javascript file. When you save the file, the js object will notice. autowatch 0 turns off file watching.

compile

Arguments

filename [symbol]
Recompiles the current file. If followed by a symbol, will load, compile, and set the currently loaded Javascript file to be the file specified by the symbol argument.

delprop

Arguments

propertyname [symbol]
The word delprop, followed by a name, deletes the named property.

editfontsize

Arguments

font-size [int]
Changes the font-size of the text used in the editing window which contains the object's Javascript source file.

getprop

Arguments

property [symbol]
The word getprop, followed by a name, outputs the value of the property name stored in the object out the left outlet.

loadbang

Invokes the function named loadbang if defined. This message is sent when the file is loaded.

open

Opens the text window where the object's Javascript source file can be edited.

setprop

Arguments

property [symbol]
values [list]
The word setprop, followed by name and one or more names or numbers, sets the named property to what follows the name. For example, after sending setprop xyz 1 2 3 to a js object. the xyz property would have a value of the list 1 2 3.

statemessage

Arguments

messages [list]
Allows for the testing of messages passed to functions within the Javascript source file.

wclose

Closes the text window where the object's Javascript source file is edited.

Methods and Inlets

All messages listed below can be sent to any inlet of the js object. The Javascript inlet property reveals the inlet that received the message that invoked the currently running script.

Output

anything

Numbers, lists, or symbols are sent out the js object's outlets when the Javascript code executing within the js object invokes the outlet function.

See Also

Name Description
Lua in Max Lua in Max
JavaScript Usage JavaScript Usage
jstrigger Execute Javascript instructions sequentially
jsui Javascript user interfaces and graphics
mxj Execute Java in Max
Max JS Tutorial 1: Basic JavaScript Max JS Tutorial 1: Basic JavaScript
Max JS Tutorial 2: JavaScript Scripting Max JS Tutorial 2: JavaScript Scripting
Max JS Tutorial 3: JavaScript Tasks, Arguments, and Globals Max JS Tutorial 3: JavaScript Tasks, Arguments, and Globals
Tutorial 45: Introduction to using Jitter within JavaScript Tutorial 45: Introduction to using Jitter within JavaScript
Tutorial 46: Manipulating Matrix Data using JavaScript Tutorial 46: Manipulating Matrix Data using JavaScript
Tutorial 47: Using Jitter Object Callbacks in JavaScript Tutorial 47: Using Jitter Object Callbacks in JavaScript