UI Utilities [omni.isaac.ui]

The Isaac Sim UI Utilities extension provides a helper functions for creating robot-centric UI elements.

Shared UI Elements

ui_utils.setup_ui_headers(file_path, title='My Custom Extension', doc_link='https://docs.omniverse.nvidia.com/isaacsim/latest/index.html', overview='')

Creates the Standard UI Elements at the top of each Isaac Extension.

Parameters

ext_id (str) – Extension ID.
file_path (str) – File path to source code.
title (str, optional) – Name of Extension. Defaults to “My Custom Extension”.
doc_link (str, optional) – Hyperlink to Documentation. Defaults to “https://docs.omniverse.nvidia.com/isaacsim/latest/index.html”.
overview (str, optional) – Overview Text explaining the Extension. Defaults to “”.

Builder Functions

ui_utils.btn_builder(type='button', text='button', tooltip='', on_clicked_fn=None)

Creates a stylized button.

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “button”.
text (str, optional) – Text rendered on the button. Defaults to “button”.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (Callable, optional) – Call-back function when clicked. Defaults to None.

Returns

Button

Return type

ui.Button

ui_utils.state_btn_builder(type='state_button', a_text='STATE A', b_text='STATE B', tooltip='', on_clicked_fn=None)

Creates a State Change Button that changes text when pressed.

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “button”.
a_text (str, optional) – Text rendered on the button for State A. Defaults to “STATE A”.
b_text (str, optional) – Text rendered on the button for State B. Defaults to “STATE B”.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (Callable, optional) – Call-back function when clicked. Defaults to None.

ui_utils.multi_btn_builder(type='multi_button', count=2, text=['button', 'button'], tooltip=['', '', ''], on_clicked_fn=[None, None])

Creates a Row of Stylized Buttons

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “multi_button”.
count (int, optional) – Number of UI elements to create. Defaults to 2.
text (list, optional) – List of text rendered on the UI elements. Defaults to [“button”, “button”].
tooltip (list, optional) – List of tooltips to display over the UI elements. Defaults to [“”, “”, “”].
on_clicked_fn (list, optional) – List of call-backs function when clicked. Defaults to [None, None].

Returns

List of Buttons

Return type

list(ui.Button)

ui_utils.cb_builder(type='checkbox', default_val=False, tooltip='', on_clicked_fn=None)

Creates a Stylized Checkbox

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “checkbox”.
default_val (bool, optional) – Checked is True, Unchecked is False. Defaults to False.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (Callable, optional) – Call-back function when clicked. Defaults to None.

Returns

model

Return type

ui.SimpleBoolModel

ui_utils.multi_cb_builder(type='multi_checkbox', count=2, text=[' ', ' '], default_val=[False, False], tooltip=['', '', ''], on_clicked_fn=[None, None])

Creates a Row of Stylized Checkboxes.

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “multi_checkbox”.
count (int, optional) – Number of UI elements to create. Defaults to 2.
text (list, optional) – List of text rendered on the UI elements. Defaults to [” “, ” “].
default_val (list, optional) – List of default values. Checked is True, Unchecked is False. Defaults to [False, False].
tooltip (list, optional) – List of tooltips to display over the UI elements. Defaults to [“”, “”, “”].
on_clicked_fn (list, optional) – List of call-backs function when clicked. Defaults to [None, None].

Returns

List of models

Return type

list(ui.SimpleBoolModel)

ui_utils.str_builder(type='stringfield', default_val=' ', tooltip='', on_clicked_fn=None, use_folder_picker=False, read_only=False, item_filter_fn=None, bookmark_label=None, bookmark_path=None, folder_dialog_title='Select Output Folder', folder_button_title='Select Folder')

Creates a Stylized Stringfield Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “stringfield”.
default_val (str, optional) – Text to initialize in Stringfield. Defaults to ” “.
tooltip (str, optional) – Tooltip to display over the UI elements. Defaults to “”.
use_folder_picker (bool, optional) – Add a folder picker button to the right. Defaults to False.
read_only (bool, optional) – Prevents editing. Defaults to False.
item_filter_fn (Callable, optional) – filter function to pass to the FilePicker
bookmark_label (str, optional) – bookmark label to pass to the FilePicker
bookmark_path (str, optional) – bookmark path to pass to the FilePicker

Returns

model of Stringfield

Return type

AbstractValueModel

ui_utils.int_builder(type='intfield', default_val=0, tooltip='', min=- 9223372036854775807, max=9223372036854775807)

Creates a Stylized Intfield Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “intfield”.
default_val (int, optional) – Default Value of UI element. Defaults to 0.
tooltip (str, optional) – Tooltip to display over the UI elements. Defaults to “”.
min (int, optional) – Minimum limit for int field. Defaults to sys.maxsize * -1
max (int, optional) – Maximum limit for int field. Defaults to sys.maxsize * 1

Returns

model

Return type

AbstractValueModel

ui_utils.float_builder(type='floatfield', default_val=0, tooltip='', min=- inf, max=inf, step=0.1, format='%.2f')

Creates a Stylized Floatfield Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “floatfield”.
default_val (int, optional) – Default Value of UI element. Defaults to 0.
tooltip (str, optional) – Tooltip to display over the UI elements. Defaults to “”.

Returns

model

Return type

AbstractValueModel

ui_utils.combo_cb_str_builder(type='checkbox_stringfield', default_val=[False, ' '], tooltip='', on_clicked_fn=<function <lambda>>, use_folder_picker=False, read_only=False, folder_dialog_title='Select Output Folder', folder_button_title='Select Folder')

Creates a Stylized Checkbox + Stringfield Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “checkbox_stringfield”.
default_val (str, optional) – Text to initialize in Stringfield. Defaults to [False, ” “].
tooltip (str, optional) – Tooltip to display over the UI elements. Defaults to “”.
use_folder_picker (bool, optional) – Add a folder picker button to the right. Defaults to False.
read_only (bool, optional) – Prevents editing. Defaults to False.

Returns

(cb_model, str_field_model)

Return type

Tuple(ui.SimpleBoolModel, AbstractValueModel)

ui_utils.dropdown_builder(type='dropdown', default_val=0, items=['Option 1', 'Option 2', 'Option 3'], tooltip='', on_clicked_fn=None)

Creates a Stylized Dropdown Combobox

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “dropdown”.
default_val (int, optional) – Default index of dropdown items. Defaults to 0.
items (list, optional) – List of items for dropdown box. Defaults to [“Option 1”, “Option 2”, “Option 3”].
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (Callable, optional) – Call-back function when clicked. Defaults to None.

Returns

model

Return type

AbstractItemModel

ui_utils.multi_dropdown_builder(type='multi_dropdown', count=2, default_val=[0, 0], items=[['Option 1', 'Option 2', 'Option 3'], ['Option A', 'Option B', 'Option C']], tooltip='', on_clicked_fn=[None, None])

Creates a Stylized Multi-Dropdown Combobox

Returns

model

Return type

AbstractItemModel

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “multi_dropdown”.
count (int, optional) – Number of UI elements. Defaults to 2.
default_val (list(int), optional) – List of default indices of dropdown items. Defaults to 0.. Defaults to [0, 0].
items (list(list), optional) – List of list of items for dropdown boxes. Defaults to [[“Option 1”, “Option 2”, “Option 3”], [“Option A”, “Option B”, “Option C”]].
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (list(Callable), optional) – List of call-back function when clicked. Defaults to [None, None].

Returns

list(models)

Return type

list(AbstractItemModel)

ui_utils.combo_cb_dropdown_builder(type='checkbox_dropdown', default_val=[False, 0], items=['Option 1', 'Option 2', 'Option 3'], tooltip='', on_clicked_fn=[<function <lambda>>, None])

Creates a Stylized Dropdown Combobox with an Enable Checkbox

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “checkbox_dropdown”.
default_val (list, optional) – list(cb_default, dropdown_default). Defaults to [False, 0].
items (list, optional) – List of items for dropdown box. Defaults to [“Option 1”, “Option 2”, “Option 3”].
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (list, optional) – List of callback functions. Defaults to [lambda x: None, None].

Returns

(cb_model, combobox)

Return type

Tuple(ui.SimpleBoolModel, ui.ComboBox)

ui_utils.combo_intfield_slider_builder(type='intfield_stringfield', default_val=0.5, min=0, max=1, step=0.01, tooltip=['', ''])

Creates a Stylized IntField + Stringfield Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “intfield_stringfield”.
default_val (float, optional) – Default Value. Defaults to 0.5.
min (int, optional) – Minimum Value. Defaults to 0.
max (int, optional) – Maximum Value. Defaults to 1.
step (float, optional) – Step. Defaults to 0.01.
tooltip (list, optional) – List of tooltips. Defaults to [“”, “”].

Returns

(flt_field_model, flt_slider_model)

Return type

Tuple(AbstractValueModel, IntSlider)

ui_utils.combo_floatfield_slider_builder(type='floatfield_stringfield', default_val=0.5, min=0, max=1, step=0.01, tooltip=['', ''])

Creates a Stylized FloatField + FloatSlider Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “floatfield_stringfield”.
default_val (float, optional) – Default Value. Defaults to 0.5.
min (int, optional) – Minimum Value. Defaults to 0.
max (int, optional) – Maximum Value. Defaults to 1.
step (float, optional) – Step. Defaults to 0.01.
tooltip (list, optional) – List of tooltips. Defaults to [“”, “”].

Returns

(flt_field_model, flt_slider_model)

Return type

Tuple(AbstractValueModel, IntSlider)

ui_utils.scrolling_frame_builder(type='scrolling_frame', default_val='No Data', tooltip='')

Creates a Labeled Scrolling Frame with CopyToClipboard button

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “scrolling_frame”.
default_val (str, optional) – Default Text. Defaults to “No Data”.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.

Returns

label

Return type

ui.Label

ui_utils.combo_cb_scrolling_frame_builder(type='cb_scrolling_frame', default_val=[False, 'No Data'], tooltip='', on_clicked_fn=<function <lambda>>)

Creates a Labeled, Checkbox-enabled Scrolling Frame with CopyToClipboard button

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “cb_scrolling_frame”.
default_val (list, optional) – List of Checkbox and Frame Defaults. Defaults to [False, “No Data”].
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.
on_clicked_fn (Callable, optional) – Callback function when clicked. Defaults to lambda x : None.

Returns

(model, label)

Return type

list(SimpleBoolModel, ui.Label)

ui_utils.xyz_builder(tooltip='', axis_count=3, default_val=[0.0, 0.0, 0.0, 0.0], min=- inf, max=inf, step=0.001, on_value_changed_fn=[None, None, None, None])

[summary]

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “”.
axis_count (int, optional) – Number of Axes to Display. Max 4. Defaults to 3.
default_val (list, optional) – List of default values. Defaults to [0.0, 0.0, 0.0, 0.0].
min (float, optional) – Minimum Float Value. Defaults to float(“-inf”).
max (float, optional) – Maximum Float Value. Defaults to float(“inf”).
step (float, optional) – Step. Defaults to 0.001.
on_value_changed_fn (list, optional) – List of callback functions for each axes. Defaults to [None, None, None, None].

Returns

list(model)

Return type

list(AbstractValueModel)

ui_utils.color_picker_builder(type='color_picker', default_val=[1.0, 1.0, 1.0, 1.0], tooltip='Color Picker')

Creates a Color Picker Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “color_picker”.
default_val (list, optional) – List of (R,G,B,A) default values. Defaults to [1.0, 1.0, 1.0, 1.0].
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “Color Picker”.

Returns

ui.ColorWidget.model

Return type

AbstractItemModel

ui_utils.progress_bar_builder(type='progress_bar', default_val=0, tooltip='Progress')

Creates a Progress Bar Widget

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
type (str, optional) – Type of UI element. Defaults to “progress_bar”.
default_val (int, optional) – Starting Value. Defaults to 0.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “Progress”.

Returns

ui.ProgressBar().model

Return type

AbstractValueModel

Plotting Functions

ui_utils.plot_builder(data=None, min=- 1, max=1, type=omni.ui.Type.LINE, value_stride=1, color=None, tooltip='')

Creates a stylized static plot

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
data (list(float), optional) – Data to plot. Defaults to None.
min (int, optional) – Minimum Y Value. Defaults to -1.
max (int, optional) – Maximum Y Value. Defaults to 1.
type (ui.Type, optional) – Plot Type. Defaults to ui.Type.LINE.
value_stride (int, optional) – Width of plot stride. Defaults to 1.
color (int, optional) – Plot color. Defaults to None.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.

Returns

plot

Return type

ui.Plot

ui_utils.combo_cb_plot_builder(default_val=False, on_clicked_fn=<function <lambda>>, data=None, min=-1, max=1, type=omni.ui.Type.LINE, value_stride=1, color=None, tooltip='')

Creates a Checkbox-Enabled dyanamic plot

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
default_val (bool, optional) – Checkbox default. Defaults to False.
on_clicked_fn (Callable, optional) – Checkbox Callback function. Defaults to lambda x: None.
data (list(), optional) – Data to plat. Defaults to None.
min (int, optional) – Min Y Value. Defaults to -1.
max (int, optional) – Max Y Value. Defaults to 1.
type (ui.Type, optional) – Plot Type. Defaults to ui.Type.LINE.
value_stride (int, optional) – Width of plot stride. Defaults to 1.
color (int, optional) – Plot color. Defaults to None.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.

Returns

(cb_model, plot)

Return type

list(SimpleBoolModel, ui.Plot)

ui_utils.xyz_plot_builder(data=[], min=- 1, max=1, tooltip='')

Creates a stylized static XYZ plot

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
data (list(float), optional) – Data to plot. Defaults to [].
min (int, optional) – Minimum Y Value. Defaults to -1.
max (int, optional) – Maximum Y Value. Defaults to “”.
tooltip (str, optional) – Tooltip to display over the Label.. Defaults to “”.

Returns

list(x_plot, y_plot, z_plot)

Return type

list(ui.Plot)

ui_utils.combo_cb_xyz_plot_builder(default_val=False, on_clicked_fn=<function <lambda>>, data=[], min=-1, max=1, type=omni.ui.Type.LINE, value_stride=1, tooltip='')

[summary]

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
default_val (bool, optional) – Checkbox default. Defaults to False.
on_clicked_fn (Callable, optional) – Checkbox Callback function. Defaults to lambda x: None.
list (data) – Data to plat. Defaults to None.
min (int, optional) – Min Y Value. Defaults to -1.
max (int, optional) – Max Y Value. Defaults to 1.
type (ui.Type, optional) – Plot Type. Defaults to ui.Type.LINE.
value_stride (int, optional) – Width of plot stride. Defaults to 1.
tooltip (str, optional) – Tooltip to display over the Label. Defaults to “”.

Returns

([plot_0, plot_1, plot_2], [val_model_x, val_model_y, val_model_z])

Return type

Tuple(list(ui.Plot), list(AbstractValueModel))

Aesthetic Functions

ui_utils.add_separator(): Aesthetic element to adds a Line Separator.

UI Element Wrappers

class Frame(enabled: bool = True, visible: bool = True, build_fn: Optional[Callable] = None)

Create a Frame UI element

Parameters

enabled (bool, optional) – Frame is enabled. Defaults to True.
visible (bool, optional) – Frame is visible. Defaults to True.
build_fn (Callable, optional) – A function that can be called to specify what should fill the Frame. Function should take no arguments. Return values will not be used. Defaults to None.

property frame: omni.ui.Frame: Returns: omni.ui.Frame: A UI Frame

rebuild(): Rebuild the Frame using the specified build_fn

set_build_fn(build_fn: Callable)

Set the build_fn to use when rebuilding the frame.

Parameters: build_fn (Callable) – Build function to use when rebuilding the frame. Function should take no arguments. Return values will not be used.

class CollapsableFrame(title: str, collapsed: bool = True, enabled: bool = True, visible: bool = True, build_fn: Optional[Callable] = None)

Create a CollapsableFrame UI element

Parameters

title (str) – Title of Collapsable Frame
collapsed (bool, optional) – Frame is collapsed. Defaults to True.
enabled (bool, optional) – Frame is enabled. Defaults to True.
visible (bool, optional) – Frame is visible. Defaults to True.
build_fn (Callable, optional) – A function that can be called to specify what should fill the Frame. Function should take no arguments. Return values will not be used. Defaults to None.

property collapsed: bool: Returns: bool: CollapsableFrame is collapsed

property title: str: Returns: str: Title text of CollapsableFrame

class ScrollingFrame(num_lines=None, enabled: bool = True, visible: bool = True, build_fn: Optional[Callable] = None)

Create a ScrollingFrame UI element with a specified size.

Parameters

num_lines (int, optional) – Determines height of ScrollingFrame element in terms of the typical line height of UI elements. If not specified, the ScrollingFrame will fill the space it can in the UI Window.
enabled (bool, optional) – Frame is enabled. Defaults to True.
visible (bool, optional) – Frame is visible. Defaults to True.
build_fn (Callable, optional) – A function that can be called to specify what should fill the Frame. Function should take no arguments. Return values will not be used. Defaults to None.

set_num_lines(num_lines: int)

Set the height of the ScrollingFrame element in terms of the typical line height of other UI elements.

Parameters: num_lines (int) – Number of lines that should be shown in a ScrollingFrame.

class IntField(label: str, tooltip: str = '', default_value: int = 0, lower_limit: Optional[int] = None, upper_limit: Optional[int] = None, on_value_changed_fn: Optional[Callable] = None)

Creates a IntField UI element.

Parameters

label (str) – Short descriptive text to the left of the IntField.
tooltip (str, optional) – Text to appear when the mouse hovers over the IntField. Defaults to “”.
default_value (int, optional) – Default value of the IntField. Defaults to 0.
lower_limit (int, optional) – Lower limit of float. Defaults to None.
upper_limit (int, optional) – Upper limit of float. Defaults to None.
on_value_changed_fn (Callable, optional) – Function to be called when the value of the int is changed. The function should take an int as an argument. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property int_field: omni.ui.IntField: Returns: omni.ui.IntField: UI IntField elements

get_value() → int

Get the current value of the int field

Returns: Current value of the int field
Return type: int

get_upper_limit() → int

Get the upper limit on the IntField.

Returns: Upper Limit on IntField
Return type: int

get_lower_limit() → int

Get the lower limit on the IntField.

Returns: Lower Limit on IntField
Return type: int

set_value(val: int)

Set the value in the IntField

Parameters: val (int) – Value to fill IntField

set_upper_limit(upper_limit: int)

Set upper limit of IntField. If current value is higher than upper_limit, the current value will be clipped to upper_limit

Parameters: upper_limit (int) – Upper limit of IntField

set_lower_limit(lower_limit: int)

Set lower limit of IntField. If current value is lower than lower_limit, the current value will be clipped to lower_limit

Parameters: lower_limit (int) – lower limit of IntField

set_on_value_changed_fn(on_value_changed_fn: Callable)

Set function that is called when the value of the IntField is modified

Parameters: on_value_changed_fn (Callable) – Function that is called when the value of the IntField is modified. Function should take a int as the argument. The return value will not be used.

class FloatField(label: str, tooltip: str = '', default_value: float = 0.0, step: float = 0.01, format: str = '%.2f', lower_limit: Optional[float] = None, upper_limit: Optional[float] = None, on_value_changed_fn: Optional[Callable] = None)

Creates a FloatField UI element.

Parameters

label (str) – Short descriptive text to the left of the FloatField.
tooltip (str, optional) – Text to appear when the mouse hovers over the FloatField. Defaults to “”.
default_value (float, optional) – Default value of the Float Field. Defaults to 0.0.
step (float, optional) – Smallest increment that the user can change the float by when dragging mouse. Defaults to 0.01.
format (str, optional) – Formatting string for float. Defaults to “%.2f”.
lower_limit (float, optional) – Lower limit of float. Defaults to None.
upper_limit (float, optional) – Upper limit of float. Defaults to None.
on_value_changed_fn (Callable, optional) – Function to be called when the value of the float is changed. The function should take a float as an argument. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property float_field: omni.ui.FloatField: Returns: omni.ui.FloatField: UI FloatField element

get_value() → float

Return the current value of the FloatField

Returns: Current value of the FloatField
Return type: float

get_upper_limit() → float

Get the upper limit on the FloatField

Returns: Upper limit on FloatField
Return type: float

get_lower_limit() → float

Get the lower limit on the FloatField

Returns: Lower limit on FloatField
Return type: float

set_value(val: float)

Set the value in the FloatField

Parameters: val (float) – Value to fill FloatField

set_upper_limit(upper_limit: float)

Set upper limit of FloatField. If current value is higher than upper_limit, the current value will be clipped to upper_limit

Parameters: upper_limit (float) – Upper limit of FloatField

set_lower_limit(lower_limit: float)

Set lower limit of FloatField. If current value is lower than lower_limit, the current value will be clipped to lower_limit

Parameters: lower_limit (float) – lower limit of FloatField

set_on_value_changed_fn(on_value_changed_fn: Callable)

Set function that is called when the value of the FloatField is modified

Parameters: on_value_changed_fn (Callable) – Function that is called when the value of the FloatField is modified. Function should take a float as the argument. The return value will not be used.

class StringField(label: str, tooltip: str = '', default_value: str = '', read_only=False, multiline_okay=False, on_value_changed_fn: Optional[Callable] = None, use_folder_picker=False, item_filter_fn=None, bookmark_label=None, bookmark_path=None, folder_dialog_title='Select Output Folder', folder_button_title='Select Folder')

Create StringField UI Element.

Starting at use_folder_picker, the arguments to the StringField all pertain to the folder_picker. If the folder_picker is not used, these arguments may all be ignored.

Parameters

label (str, optional) – Label to the left of the UI element. Defaults to “”.
tooltip (str, optional) – Tooltip to display over the UI elements. Defaults to “”.
default_val (str, optional) – Text to initialize in Stringfield. Defaults to ” “.
read_only (bool, optional) – Prevents editing. Defaults to False.
multiline_okay (bool, optional) – If True, allow newline character in input strings. Defaults to False.
on_value_changed_fn (Callable, optional) – The function should take a string as an argument. The return value will not be used. Defaults to None.
use_folder_picker (bool, optional) – Add a folder picker button to the right. Defaults to False.
item_filter_fn (Callable, optional) – Filter function to pass to the FilePicker. This function should take a string as an argument and return a boolean. When the user opens the file picker, every file in the directory they are viewing will be passed to item_filter_fn, and when True is returned, the file will be shown. When False is returned, the file will not be shown. This can be used to ensure that the user may only select valid file types.
bookmark_label (str, optional) – Bookmark label to pass to the FilePicker. This will create a bookmark when the file picker is used with the label specified here.
bookmark_path (str, optional) – Bookmark path to pass to the FilePicker. This will create a bookmark when the file picker is used with the path specified here.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property string_field: omni.ui.StringField: Returns: omni.ui.StringField: UI StringField element

property file_picker_frame: omni.ui.Frame: Returns: omni.ui.Frame: UI Frame containing FilePicker

property file_picker_btn: omni.ui.Button: Returns: omni.ui.Button: Button to activate file picker

get_value() → str

Return the current value of the StringField

Returns: Current value of the StringField
Return type: str

set_value(val: str)

Set the value of the StringField

Parameters: val (str) – Value to fill StringField

set_on_value_changed_fn(on_value_changed_fn: Callable)

Set function that is called when the value of the StringField is modified

Parameters: on_value_changed_fn (Callable) – Function that is called when the value of the StringField is modified. Function should take a string as the argument. The return value will not be used.

set_item_filter_fn(item_filter_fn: Callable)

Set the filter function that will be used with the file picker

Parameters: item_filter_fn (Callable) – Filter function that will be called to filter the files shown in the picker. This function should take a string file_path as the argument. The return value should be a bool, with True indicating the the file should be shown to the user in the file picker.

set_read_only(read_only: bool)

Set this StringField to be read only

Parameters: read_only (bool) – If True, StringField cannot be modified through the UI; it can still be modified programmatically with set_value()

set_multiline_okay(multiline_okay: bool)

Set the StringFiled to allow the newline character

Parameters: multiline_okay (bool) – If True, allow newline character in strings.

add_folder_picker_icon(on_click_fn, item_filter_fn=None, bookmark_label=None, bookmark_path=None, dialog_title='Select Output Folder', button_title='Select Folder')

class Button(label: str, text: str, tooltip='', on_click_fn=None)

Create a Button UI Element

Parameters

label (str) – Short descriptive text to the left of the Button
text (str) – Text on the Button
tooltip (str, optional) – Text to appear when the mouse hovers over the Button. Defaults to “”.
on_click_fn (Callable, optional) – Callback function that will be called when the button is pressed. Function should take no arguments. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property button: omni.ui.Button: Returns: omni.ui.Button: UI Button element

set_on_click_fn(on_click_fn: Callable)

Set the callback function for when the Button is clicked.

Parameters: on_click_fn (Callable) – Callback function for when Button is clicked. The function should take a single bool argument. The return value will not be used.

trigger_click(): Trigger identical behavior as if the user pressed the Button through the UI.

class CheckBox(label: str, default_value: bool = False, tooltip='', on_click_fn=None)

Create a CheckBox UI Element

Parameters

label (str) – Short descriptive text to the left of the CheckBox
default_value (bool, optional) – If True, CheckBox will be checked. Defaults to False.
tooltip (str, optional) – Text to appear when the mouse hovers over the CheckBox. Defaults to “”.
on_click_fn (_type_, optional) – Callback function that will be called when the CheckBox is pressed. Function should take a single bool argument. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property checkbox: omni.ui.CheckBox: Returns: omni.ui.CheckBox: UI CheckBox element

get_value() → bool

Returns: Check box is checked
Return type: bool

set_value(val: bool)

Parameters: val (bool) – If True, set CheckBox to checked state

set_on_click_fn(on_click_fn: Callable)

Set the function that will be called when the CheckBox is clicked.

Parameters: on_click_fn (Callable) – Callback function for when CheckBox is clicked. The function should take a single bool argument. The return value will not be used.

class StateButton(label: str, a_text: str, b_text: str, tooltip='', on_a_click_fn: Optional[Callable] = None, on_b_click_fn: Optional[Callable] = None, physics_callback_fn: Optional[Callable] = None)

Creates a State Button UI element. A StateButton is a button that changes between two states A and B when clicked. In state A, the StateButton has a_text written on it, and in state B, the StateButton has b_text written on it.

Parameters

label (str) – Short descriptive text to the left of the StateButton
a_text (str) – Text on the StateButton in one of its two states
b_text (str) – Text on the StateButton in the other of its two states
tooltip (str, optional) – Text that appears when the mouse hovers over the button. Defaults to “”.
on_a_click_fn (Callable, optional) – A function that should be called when the button is clicked while in state A. Function should have 0 arguments. The return value will not be used. Defaults to None.
on_b_click_fn (Callable, optional) – A function that should be called when the button is clicked while in state B. Function should have 0 arguments. The return value will not be used. Defaults to None.
physics_callback_fn (Callable, optional) – A function that will be called on every physics step while the button is in state B (a_text was pressed). The function should have one argument for physics step size (float). The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property state_button: omni.ui.Button: Returns: omni.ui.Button: UI Button element

set_physics_callback_fn(physics_callback_fn: Callable)

Set a physics callback function that will be called on every physics step while the StateButton is in state B.

Parameters: physics_callback_fn (Callable) – A function that will be called on every physics step while the button is in state B (a_text was pressed). The function should have one argument for physics step size (float). The return value will not be used.

set_on_a_click_fn(on_a_click_fn: Callable)

Set a function that is called when the button is clicked in state A.

Parameters: on_a_click_fn (Callable) – A function that is called when the button is clicked in state A. Function should take no arguments. The return value will not be used.

set_on_b_click_fn(on_b_click_fn: Callable)

Set a function that is called when the button is clicked in state B.

Parameters: on_b_click_fn (Callable) – A function that is called when the button is clicked in state B. Function should take no arguments. The return value will not be used.

is_in_a_state() → bool

Return True if the StateButton is in the a state. False implies that it is in the b state.

Returns: True when the StateButton is in the b state.
Return type: bool

trigger_click_if_a_state(): If in the A state, trigger button to execute the same behavior as if it were clicked by the user. If the button is in the B state, nothing will happen.

trigger_click_if_b_state(): If in the B state, trigger button to execute the same behavior as if it were clicked by the user. If the button is in the A state, nothing will happen. This is distinct from calling reset() because the user on_b_click_fn() will be triggered.

get_current_text() → str: Get the current text on the button.

reset(): Reset StateButton to state A.

cleanup(): Remove physics callback created by the StateButton if exists.

class DropDown(label: str, tooltip: str = '', populate_fn: Optional[Callable] = None, on_selection_fn: Optional[Callable] = None, keep_old_selections: bool = False)

Create a DropDown UI element. A DropDown menu can be populated by the user, with a callback function specified for when an item is selected.

Parameters

label (str) – Short descriptive text to the left of the DropDown
tooltip (str, optional) – Text to appear when the mouse hovers over the DropDown. Defaults to “”.
populate_fn (Callable, optional) – A user-defined function that returns a list[str] of items that should populate the drop-down menu. This Function should have 0 arguments. Defaults to None.
on_selection_fn (Callable, optional) – A user-defined callback function for when an element is selected from the DropDown. The function should take in a string argument of the selection. The return value will not be used. Defaults to None.
keep_old_selections (bool, optional) – When the DropDown is repopulated with the user-defined populate_fn, the default behavior is to reset the selection in the DropDown to be at index 0. If the user sets keep_old_selections=True, when the DropDown is repopulated and the old selection is still one of the options, the new selection will match the old selection. Defaults to False.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property combobox: omni.ui.ComboBox: Returns: omni.ui.ComboBox: UI ComboBox element.

repopulate(): A function that the user can call to make the DropDown menu repopulate. This will call the populate_fn set by the user.

set_populate_fn(populate_fn: Callable, repopulate: bool = True)

Set the populate_fn for this DropDown

Parameters

populate_fn (Callable) – Function used to specify the options that fill the DropDown. Function should take no arguments and return a list[str].
repopulate (bool, optional) – If true, repopulate the DropDown using the new populate_fn. Defaults to True.

get_items() → List[str]

Get the items in the DropDown

Returns: A list of the options in the DropDown
Return type: List[str]

get_selection_index() → int

Get index of selection in DropDown menu

Returns: Index of selection in DropDown menu
Return type: int

get_selection() → str

Get current selection in DropDown

Returns: Current selection in DropDown
Return type: str

set_items(items: List[str], select_index: Optional[int] = None)

Set the items in the DropDown explicitly.

Parameters

items (List[str]) – New set of items in the DropDown
select_index (int, optional) – Index of item to select. If left as None, behavior is determined by the keep_old_selections flag. Defaults to None.

set_selection(selection: str)

Set the selected item in the DropDown. If the specifified selection is not in the DropDown, nothing will happen.

Parameters: selection (str) – Item to select in the DropDown

set_selection_by_index(select_index: int)

Set the selected item in the DropDown by index. If the provided index is out of bounds, nothing will happen.

Parameters: select_index (int) – Index of item to select from DropDown

set_on_selection_fn(on_selection_fn: Callable)

Set the function that gets called when a new item is selected from the DropDown

Parameters: on_selection_fn (Callable) – A function that is called when a new item is selected from the DropDown. he function should take in a string argument of the selection. Its return value is not used.

set_keep_old_selection(val: bool)

Set keep_old_selection flag to determine behavior when repopulating the DropDown

Parameters: val (bool) – When the DropDown is repopulated with the user-defined populate_fn, the default behavior is to reset the selection in the DropDown to be at index 0. If the user sets keep_old_selections=True, when the DropDown is repopulated and the old selection is still one of the options, the new selection will match the old selection, and the on_selection_fn() will not be called.

set_populate_fn_to_find_all_usd_objects_of_type(object_type: str, repopulate=True)

Set the populate_fn to find all objects of a specified type on the USD stage. This is included as a convenience function to fulfill one common use-case for a DropDown menu. This overrides the populate_fn set by the user.

Parameters

object_type (str) – A string name of the type of USD object matching the output of omni.isaac.core.utils.prims.get_prim_object_type(prim_path)
repopulate (bool, optional) – Repopulate the DropDown immediately. Defaults to True.

trigger_on_selection_fn_with_current_selection(): Call the user on_selection_fn() with whatever item is currently selected in the DropDown.

class ColorPicker(label: str, default_value: List[float] = [1.0, 1.0, 1.0, 1.0], tooltip: str = '', on_color_picked_fn: Optional[Callable] = None)

Create a ColorPicker UI element to allow user-selection of an RGBA color

Parameters

label (str) – Short descriptive text to the left of the ColorPicker
default_value (List[float], optional) – RGBA color values between 0 and 1. Defaults to [1.0, 1.0, 1.0, 1.0].
tooltip (str, optional) – Text to appear when the mouse hovers over the ColorPicker. Defaults to “”.
on_color_picked_fn (Callable, optional) – Function that will be called if the user picks a new color. Function should expect a List[float] as an argument with four RGBA color values between 0 and 1. The return value will not be used.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property color_picker: omni.ui.ColorWidget: Returns: omni.ui.ColorWidget: UI ColorWidget element

get_color() → List[float]

Get the RGBA value of the selected color

Returns: RGBA color value with four values between 0 and 1
Return type: List[float]

set_color(color: List[float])

Set the RGBA color value of the selected color

Parameters: color (List[float]) – RGBA color value with four values between 0 and 1

set_on_color_picked_fn(on_color_picked_fn: Callable)

Set the function that should be called if the user picks a new color

Parameters: on_color_picked_fn (Callable) – Function that will be called if the user picks a new color. Function should expect a List[float] as an argument with four RGBA color values between 0 and 1. The return value will not be used.

class TextBlock(label: str, text: str = '', tooltip: str = '', num_lines=5, include_copy_button: bool = True)

Create a text block that is only modifiable through code. The user may not set the value of the text in the UI.

Parameters

label (str) – Short description of the contents of the TextBlock
text (str, optional) – Text to put in the TextBlock. Defaults to “”.
tooltip (str, optional) – Text to appear when the mouse hovers over the TextBlock. Defaults to “”.
num_lines (int, optional) – Number of lines that should be visible in the TextBlock at one time. Defaults to 5.
include_copy_button (bool, optional) – Include a copy_to_clipboard button. Defaults to True.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property scrolling_frame: omni.ui.ScrollingFrame: Returns: omni.ui.ScrollingFrame: Scrolling Frame that contains the TextBlock text

property copy_btn: omni.ui.Button: Returns: omni.ui.Button: Copy Button. If the TextBlock was built without a copy button, this will return None.

property text_block: omni.ui.Label: Returns: omni.ui.Label: UI element that contains the text in the text block

get_text() → str

Returns: Text in the text block
Return type: str

set_text(text: str)

Parameters: text (str) – Set the text in the text block.

set_num_lines(num_lines: int)

Set the number of lines that should be visible in the TextBlock at one time.

Parameters: num_lines (int) – Number of lines that should be visible in the TextBlock at one time.

class XYPlot(label: str, tooltip: str = '', x_data: Union[List[List], List] = [], y_data: Union[List[List], List] = [], x_min: Optional[float] = None, x_max: Optional[float] = None, y_min: Optional[float] = None, y_max: Optional[float] = None, x_label: str = 'X', y_label: str = 'Y', plot_height: int = 10, show_legend: bool = False, legends: Optional[List[str]] = None, plot_colors: Optional[List[List[int]]] = None)

get_x_data() → List[List[float]]

x_data in the plot

Returns: A possibly ragged list of lists where each ith inner list is the x coordinates for plot i.
Return type: List[List[float]]

get_y_data() → List[List[float]]

y_data in the plot

Returns: A possibly ragged list of lists where each ith inner list is the y coordinates for plot i.
Return type: List[List[float]]

get_x_min() → float

Get the minimum value of x shown in the plot.

Returns: Minimum value of x shown in the plot.
Return type: float

get_y_min() → float

Get the minimum value of y shown in the plot.

Returns: Minimum value of y shown in the plot.
Return type: float

get_x_max() → float

Get the maximum value of x shown in the plot.

Returns: Maximum value of x shown in the plot.
Return type: float

get_y_max() → float

Get the maximum value of y shown in the plot.

Returns: Maximum value of y shown in the plot.
Return type: float

get_legends() → List[str]

Get the legends for the plotted data.

Returns: Legends for the plotted data
Return type: List[str]

get_plot_height() → int

Get the height of the plot, proportional to the height of a line of text

Returns: Height of the plot
Return type: int

get_plot_colors() → List[List[int]]

Get the colors of the data in the plot

Returns: List of lists where each inner list has length 3 corresponding to r,g,b values.
Return type: List[List[int]]

set_plot_color_by_index(index: int, r: int, g: int, b: int)

Set the color of a specific plot.

Parameters

index (int) – Index of the plot corresponding to the rows of x_data and y_data.
r (int) – Value for red in [0,255]
g (int) – Value for green in [0,255]
b (int) – Value for blue in [0,255]

set_plot_colors(plot_colors: List[List[int]])

Set the colors for every plot

Parameters: plot_colors (List[List[int]]) – A list of lists where each index corresponds to the rows of x_data and y_data. Each inner list must contain [r,g,b] color values in [0,255]

set_x_min(x_min: float)

Set the minimum value of x shown on the plot. If this value is not less than x_max, x_max will be updated to x_min + 1.

Parameters: x_min (float) – Minimum value of x shown on the plot.

set_y_min(y_min: float)

Set the minimum value of y shown on the plot. If this value is not less than y_max, y_max will be updated to y_min + 1.

Parameters: y_min (float) – Minimum value of y shown on the plot.

set_x_max(x_max: float)

Set maximum value of x shown on the plot. If this value is not greater than x_min, x_min will be updated to x_max - 1.

Parameters: x_max (float) – Maximum value of x shown on the plot.

set_y_max(y_max: float)

Set maximum value of y shown on the plot. If this value is not greater than y_min, y_min will be updated to y_max - 1.

Parameters: y_max (float) – Maximum value of y shown on the plot.

set_legend_by_index(idx: int, legend: str)

Set the legend for a specific plot whose index corresponds to the rows of x_data and y_data

Parameters

idx (int) – Index of legend to set.
legend (str) – Legend

set_legends(legends: List[str])

Set legends for each plot.

Parameters: legends (List[str]) – List of legends for each plot.

set_plot_height(plot_height: int)

Set the height of the plot.

Parameters: plot_height (int) – Height of the plot, proportional to the height of a line of text.

set_show_legend(show_legend: bool)

Hide or show the legend for this Widget

Parameters: show_legend (bool) – If True, show a legend for the Widget.

set_data(x_data: Union[List[List], List], y_data: Union[List[List], List])

Set the data to plot

Parameters

x_data (Union[List[List],List]) – A possibly ragged list of lists where each ith inner list is the x coordinates for plot i. For a single plot, the data may be provided as a list of floats. x_data must have exactly the same shape as y_data.
y_data (Union[List[List],List]) – A possibly ragged list of lists where each ith inner list is the y coordinates for plot i. For a single plot, the data may be provided as a list of floats. y_data must have exactly the same shape as x_data.

set_plot_visible_by_index(index: int, visible: bool)

Hide or show a specific plot

Parameters

index (int) – Index of plot to show
visible (bool) – If True, show the plot, otherwise hide it.

Specialized UI Element Wrappers

class LoadButton(label: str, text: str, tooltip: str = '', setup_scene_fn: Optional[Callable] = None, setup_post_load_fn: Optional[Callable] = None)

Create a special type of UI button that connects to the omni.isaac.core.World to enable convenient “Load” functionality. The World acts as a scene manager that simplifies user interaction with the simulator. This provides the user with certain guarantees at the time that their callback functions are called.

The setup_scene_fn() is called with the guarantee that a World has been created. In this function, the user is meant to add the asssets they want to the USD stage. These assets then must also be added to the World. World is a singleton class. And example setup_scene_fn implementation would include:

world = World.instance() # Get the unique instance of the World

world.scene.add(usd_object) # Add the user-loaded usd object to the scene

The setup_post_load() function is called with the gurantees that the World has been created, the setup_scene_fn() has already been called, all objects that the user added to the World have been properly initialized, and the timeline is paused at timestep 0.

Parameters

label (str) – Short descriptive text to the left of the LoadButton
text (str) – Text on the LoadButton
tooltip (str, optional) – Text to appear when the mouse hovers over the LoadButton. Defaults to “”.
setup_scene_fn (Callable, optional) – A function that will be called when the LoadButton is clicked. The user should use this function to add their assets to the USD stage and to add their assets to the World. This function should take 0 arguments. The return value will not be used. Defaults to None.
setup_post_load_fn (Callable, optional) – A function that will be called when the LoadButton is clicked. The function is called with the gurantees that the World has been created, the setup_scene_fn() has already been called, all objects that the user added to the World have been properly initialized, and the timeline is paused at timestep 0. This function should take 0 arguments. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property button: omni.ui.Button: Returns: omni.ui.Button: UI Button element

set_setup_scene_fn(setup_scene_fn: Callable)

Set the setup_scene_fn that will be called when the LoadButton is clicked. The setup_scene_fn() is called with the guarantee that a World has been created. In this function, the user is meant to add the asssets they want to the USD stage. These assets then must also be added to the World. World is a singleton class. An example setup_scene_fn implementation would include:

world = World.instance() # Get the unique instance of the World world.scene.add(usd_object) # Add the user-loaded usd object to the scene

Parameters: setup_scene_fn (Callable) – A function that will be called when the LoadButton is clicked. The user should use this function to add their assets to the USD stage and to add their assets to the World. This function should take 0 arguments. The return value will not be used. Defaults to None.

set_setup_post_load_fn(setup_post_load_fn: Callable)

Set the setup_post_load_fn that will be called when the LoadButton is clicked.

Parameters: setup_post_load_fn (Callable) – A function that will be called when the LoadButton is clicked. The function is called with the gurantees that the World has been created, the setup_scene_fn() has already been called, all objects that the user added to the World have been properly initialized, and the timeline will be paused at timestep 0. This function should take 0 arguments. The return value will not be used. Defaults to None.

set_world_settings(**kwargs)

Pressing a Load Button will create a new instance of the omni.isaac.core.World. The default settings will be used unless the user specifies new settings at runtime before the Load Button is clicked.

The default settings will ensure that the physics and rendering timesteps are fixed at 1/60.0 seconds (see set_defaults argument). It is important to note that this will ensure that code is deterministic, but may not be executed in real time. I.e. physics and render dts will adjust automatically if the simulation is running too fast or slow.

Parameters

physics_dt (Optional[float], optional) – dt between physics steps. Defaults to None.
rendering_dt (Optional[float], optional) – dt between rendering steps. Note: rendering means rendering a frame of the current application and not only rendering a frame to the viewports/ cameras. So UI elements of Isaac Sim will be refereshed with this dt as well if running non-headless. Defaults to None.
stage_units_in_meters (Optional[float], optional) – The metric units of assets. This will affect gravity value..etc. Defaults to None.
physics_prim_path (Optional[str], optional) – specifies the prim path to create a PhysicsScene at, only in the case where no PhysicsScene already defined. Defaults to “/physicsScene”.
set_defaults (bool, optional) – set to True to use the defaults settings [physics_dt = 1.0/ 60.0, stage units in meters = 1 (i.e in meters), rendering_dt = 1.0 / 60.0, gravity = -9.81 m / s ccd_enabled, stabilization_enabled, gpu dynamics turned off, broadcast type is MBP, solver type is TGS]. Defaults to True.
backend (str, optional) – specifies the backend to be used (numpy or torch). Defaults to numpy.
device (Optional[str], optional) – specifies the device to be used if running on the gpu with torch backend.

class ResetButton(label: str, text: str, tooltip='', pre_reset_fn: Optional[Callable] = None, post_reset_fn: Optional[Callable] = None)

Create a special type of UI button that connects to the omni.isaac.core.World to perform a reset. If no World instance exists when this button will be clicked, this button will not create one. In this case, the button logs a warning and calls user callback functions with no guarantees on the Simulator State.

Parameters

label (str) – Short descriptive text to the left of the ResetButton.
text (str) – Text on the ResetButton
tooltip (str, optional) – Text to appear when the mouse hovers over the ResetButton. Defaults to “”.
pre_reset_fn (Callable, optional) – A function that will be called before resetting the World. This function should take 0 arguments. The return value will not be used. Defaults to None.
post_reset_fn (Callable, optional) – A function that will be called after the World is reset. When this function is called, the timeline will be paused at timestep 0, and all USD assets added to the World will be properly initialized and placed at their default positions. This function should take no arguments. The return value will not be used. Defaults to None.

property label: omni.ui.Label: Returns: omni.ui.Label: UI Label element that contains the descriptive text

property button: omni.ui.Button: Returns: omni.ui.Button: UI Button element

set_pre_reset_fn(pre_reset_fn: Callable)

Set the pre_reset_fn for when the ResetButton is clicked.

Parameters: pre_reset_fn (Callable) – A function that will be called before resetting the World. This function should take 0 arguments. The return value will not be used.

set_post_reset_fn(post_reset_fn: Callable)

Set the post_reset_fn for when the ResetButton is clicked.

Parameters: post_reset_fn (Callable) – A function that will be called after the World is reset. When this function is called, the timeline will be paused at timestep 0, and all USD assets added to the World will be properly initialized and placed at their default locations. This function should take no arguments. The return value will not be used.