SourceModule egui

egui: an easy-to-use GUI for Python!

Try the live web demo: https://www.egui.rs/#demo. Read more about egui at https://github.com/emilk/egui.

To create a GUI using egui create a Window and set its content function. The function receives a Ui, which is what you'll be using to add all the buttons and labels that you need.

Using egui§

To see what is possible to build with egui you can check out the online demo at https://www.egui.rs/#demo.

A simple example§

Here is a simple counter that can be incremented and decremented using two buttons:

import egui
from talon.egui import Window

count = egui.Mutable(0)

async def draw(ui: egui.Ui):
    async with ui.horizontal() as row:
        if row.button("−").clicked():
            count.set(count.get() - 1)
        row.label(str(count.get()))
        if row.button("+").clicked():
            count.set(count.get() + 1)

window = Window()
window.set_content(draw)
window.show()

In some GUI frameworks this would require defining multiple types and functions with callbacks or message handlers, but thanks to egui being immediate mode everything is one self-contained function!

Quick start§

import egui

my_string = egui.Mutable("")
my_boolean = egui.Mutable(True)
my_number = egui.Mutable(42.0)
my_choice = egui.Mutable("First")

async def draw(ui: egui.Ui):
    ui.label("This is a label")
    ui.hyperlink("https://github.com/emilk/egui")
    ui.text_edit_singleline(my_string)
    if ui.button("Click me").clicked():
        print("Clicked")
    ui.add(egui.Slider(my_number, 0.0, 100.0))
    ui.add(egui.DragValue(my_number))
    ui.checkbox(my_boolean, "Checkbox")
    async with ui.horizontal() as row:
        row.radio_value(my_choice, "First", "First")
        row.radio_value(my_choice, "Second", "Second")
        row.radio_value(my_choice, "Third", "Third")
    ui.separator()
    async with ui.collapsing("Click to see what is hidden!") as contents:
        contents.label("Not much, as it turns out")

Coordinate system§

The left-top corner of the screen is (0.0, 0.0), with X increasing to the right and Y increasing downwards.

egui uses logical points as its coordinate system. Those related to physical pixels by the pixels_per_point scale factor. For example, a high-dpi screen can have pixels_per_point = 2.0, meaning there are two physical screen pixels for each logical point.

Angles are in radians, and are measured clockwise from the X-axis, which has angle=0.

Understanding immediate mode§

egui is an immediate mode GUI library.

Immediate mode has its roots in gaming, where everything on the screen is painted at the display refresh rate, i.e. at 60+ frames per second. In immediate mode GUIs, the entire interface is laid out and painted at the same high rate. This makes immediate mode GUIs especially well suited for highly interactive applications.

It is useful to fully grok what "immediate mode" implies.

Here is an example to illustrate it:

if ui.button("click me").clicked():
    take_action()

This code is being executed each frame at maybe 60 frames per second. Each frame egui does these things:

lays out the letters click me in order to figure out the size of the button
decides where on screen to place the button
check if the mouse is hovering or clicking that location
choose button colors based on if it is being hovered or clicked
add a rectangle and text shapes to the list of shapes to be painted later this frame
return a Response with the Response.clicked member so the user can check for interactions

There is no button being created and stored somewhere. The only output of this call is some colored shapes, and a Response.

Similarly, consider this code:

ui.add(egui.Slider(value, 0.0, 100.0).text("My value"))

Here egui will read value (a Mutable containing a float) to display the slider, then look if the mouse is dragging the slider and if so change the value. Note that egui does not store the slider value for you - it only displays the current value, and changes it by how much the slider has been dragged in the previous few milliseconds. This means it is responsibility of the egui user to store the state (value) so that it persists between frames.

It can be useful to read the code for the toggle switch example widget to get a better understanding of how egui works: https://github.com/emilk/egui/blob/main/crates/egui_demo_lib/src/demo/toggle_switch.rs.

Read more about the pros and cons of immediate mode at https://github.com/emilk/egui#why-immediate-mode.

Multi-pass immediate mode§

By default, egui usually only does one pass for each rendered frame. However, egui supports multi-pass immediate mode. Another pass can be requested with Context.request_discard.

This is used by some widgets to cover up "first-frame jitters". For instance, the Grid needs to know the width of all columns before it can properly place the widgets. But it cannot know the width of widgets to come. So it stores the max widths of previous frames and uses that. This means the first time a Grid is shown it will guess the widths of the columns, and will usually guess wrong. This means the contents of the grid will be wrong for one frame, before settling to the correct places. Therefore Grid calls Context.request_discard when it is first shown, so the wrong placement is never visible to the end user.

This is an example of a form of multi-pass immediate mode, where earlier passes are used for sizing, and later passes for layout.

See Context.request_discard and Options.max_passes for more.

Misc§

Each widget has a Sense, which defines whether or not the widget is sensitive to clicking and/or drags.

For instance, a Button only has a Sense.click (by default). This means if you drag a button it will not respond with Response.dragged. Instead, the drag will continue through the button to the first widget behind it that is sensitive to dragging, which for instance could be a ScrollArea. This lets you scroll by dragging a scroll area (important on touch screens), just as long as you don't drag on a widget that is sensitive to drags (e.g. a Slider).

When widgets overlap it is the last added one that is considered to be on top and which will get input priority.

The widget interaction logic is run at the start of each frame, based on the output from the previous frame. This means that when a new widget shows up you cannot click it in the same frame (i.e. in the same fraction of a second), but unless the user is spider-man, they wouldn't be fast enough to do so anyways.

By running the interaction code early, egui can actually tell you if a widget is being interacted with before you add it, as long as you know its Id before-hand (e.g. using Ui.next_auto_id), by calling Context.read_response. This can be useful in some circumstances in order to style a widget, or to respond to interactions before adding the widget (perhaps on top of other widgets).

Installing additional fonts§

The default egui fonts only support latin and cryllic characters, and some emojis. To use egui with e.g. asian characters you need to install your own font (.ttf or .otf) using Context.set_fonts.

Modules§

class	Classes
commonmark	RenderHtmlFn, RenderMathFn, Alert, AlertBundle, CommonMarkCache
containers	Containers are pieces of the UI which wraps other pieces of UI. Examples: `Window`, `ScrollArea`, `Resize`, `Panel`, etc.
debug_text	This is an example of how to create a plugin for egui.
ecolor	Color conversions and types.
egui_extras	This is a crate that adds some features on top top of `egui`.
emath	Opinionated 2D math library for building GUIs.
epaint	A simple 2D graphics library for turning simple 2D shapes and text into textured triangles.
gui_zoom	Helpers for zooming the whole GUI of an app (changing `Context.pixels_per_point`).
input	The input needed by egui.
introspection	Showing UI:s for egui/epaint types.
layers	Handles paint layers, i.e. how things are sometimes painted behind or in front of other things.
load	Image loading
os	OperatingSystem
output	All the data egui returns to the backend at the end of each frame.
response	Response
style	egui theme (spacing, colors, etc).
syntax_highlighting	TextLayouter, layouter
talon	Window
text_selection	Helpers regarding text selection for labels and text edit.
util	Miscellaneous tools used by the rest of egui.
viewport	egui supports multiple viewports, corresponding to multiple native windows.
widget_style	ButtonStyle, CheckboxStyle, SeparatorStyle, TextVisuals, WidgetState
widget_text	RichText, WidgetText
widgets	Widgets are pieces of GUI such as `Label`, `Button`, `Slider` etc.

Classes Functions Constants Re-exports

Classes§

Alert
AlertBundle
Align Enum	left/center/right or top/center/bottom alignment for e.g. anchors and layouts.
Align2	Two-dimension alignment, e.g. `Align2.LEFT_TOP`.
Alpha Enum	What options to show for alpha
Area	An area on the screen that can be moved by dragging.
AreaState	State of an `Area` that is persisted between frames.
Atom	A low-level ui building block.
AtomKind Enum	The different kinds of `egui.Atom`s.
AtomLayout	`AtomLayout` was split into `WidgetAtom` (id, sense, allocation) and `ContainerAtom` (layout & painting). `WidgetAtom` is the direct replacement.
AtomLayoutResponse	Renamed to `WidgetAtomResponse`.
Atoms	A list of `Atom`s.
Brush	Controls texturing of a `egui.RectShape`.
Button	Clickable button with text.
ButtonStyle	Dedicated button style
Bytes Enum	Represents a byte buffer.
BytesLoader
BytesPoll Enum	Represents bytes which are currently being loaded.
CCursor	Character cursor.
CCursorRange	A selected text range (could be a range of length zero).
CentralPanel	A panel that covers the remainder of the screen, i.e. whatever area is left after adding other panels.
Checkbox	Boolean on/off control with text label.
CheckboxStyle	Dedicated checkbox style
CircleShape	How to paint a circle.
Classes	`Classes` is a collection of `ClassName`s that can be added to widgets or containers.
ClippedPrimitive	A `Mesh` or `PaintCallback` within a clip rectangle.
ClippedShape	A `Shape` within a clip rectangle.
ClosableTag	A tag to mark a container as closable.
CodeTheme
CollapsingHeader	A header which can be collapsed/expanded, revealing a contained `Ui` region.
CollapsingResponse	The response from showing a `CollapsingHeader`.
CollapsingState	This is a a building block for building collapsing regions.
Color32	This format is used for space-efficient color representation (32 bits).
ColorImage	A 2D RGBA color image in RAM.
Column	Specifies the properties of a column, like its width range.
ComboBox	A drop-down selection menu with a descriptive label.
ComboBoxResponse
CommonMarkCache
CommonMarkViewer
Context	Your handle to egui.
CornerRadius	How rounded the corners of things should be.
CubicBezierShape	A cubic Bézier Curve.
CursorGrab Enum
CursorIcon Enum	A mouse cursor icon.
CustomCursorImage	A bitmap cursor pushed to the integration via `PlatformOutput.cursor_image`.
DatePickerButton	Shows a date, and will open a date picker popup when clicked.
DefaultBytesLoader	Maps URI:s to `Bytes`, e.g. found with `include_bytes!`.
DefaultTextureLoader
Direction Enum	A cardinal direction, one of `LeftToRight`, `RightToLeft`, `TopDown`, `BottomUp`.
DragAndDrop	Plugin for tracking drag-and-drop payload.
DragPanButtons	Specifies which pointer buttons can be used to pan the scene by dragging.
DragScroll Enum	When `ScrollArea` should let the user scroll by dragging the content.
DragValue	A numeric value that you can change by dragging the number. More compact than a `egui.Slider`.
DroppedFile
EllipseShape	How to paint an ellipse.
Event Enum	An input event generated by the integration.
EventFilter	Controls which events that a focused widget will have exclusive access to.
FileLoader
FocusDirection Enum	A direction in which to move the keyboard focus.
FontColorTransferFunction Enum	How to convert font coverage values into alpha and color values.
FontData	A `.ttf` or `.otf` file and a font face index.
FontDefinitions	Describes a set of pre-configured fonts.
FontFamily Enum	Font of unknown size.
FontId	How to select a sized font.
FontInsert	A font to add to `FontDefinitions`, and which families to add it to.
FontPriority Enum	Whether an inserted font (or `egui.text.GlyphRasterizer`) goes before or after the existing fonts of a family.
Fonts	The collection of fonts used by `epaint`.
FontSelection Enum	A way to select `FontId`, either by picking one directly or by using a `TextStyle`.
FontTweak	Extra scale and vertical tweak to apply to all text of a certain font.
FontVariationAxis	A single variation axis of a variable font, e.g. weight (`wght`) or width (`wdth`).
Frame	A frame around some content, including margin, colors, etc.
FrameDurations	Stores the durations between each frame of an animated image
FullOutput	What egui emits each frame from `egui.Context.run_ui`.
Galley	Text that has been laid out, ready for painting.
Grid	A simple grid layout.
HandleShape Enum	Shape of the handle for sliders and similar widgets.
HexColor Enum	A wrapper around Color32 that converts to and from a hex-color string
HintingTarget Enum	How to hint glyph outlines, i.e. how aggressively to nudge them onto the pixel grid before rasterizing. Mirrors `skrifa.outline.Target`.
HoveredFile	A file about to be dropped into egui.
Hsva	Hue, saturation, value, alpha. All in the range [0, 1]. No premultiplied alpha.
HsvaGamma	Like Hsva but with the `v` value (brightness) being gamma corrected so that it is somewhat perceptually even.
Hyperlink	A clickable hyperlink, e.g. to `"https://github.com/emilk/egui"`.
Id
IdSalt	A "locally unique" identifier, e.g. to identify a child widget within a parent widget.
IdSource Enum	Is this `Ui` a root or a child of another `Ui`?
IdTypeMap
Image	A widget which displays an image.
ImageButton
ImageData Enum	An image stored in RAM.
ImageDelta	A change to an image.
ImageFit Enum	This type determines how the image should try to fit within the UI.
ImageLoader
ImageOptions
ImagePoll Enum	Represents an image which is currently being loaded.
ImageSize	This type determines the constraints on how the size of an image should be calculated.
ImageSource Enum	This type tells the `Ui` how to load an image.
ImeComposition	Visual style for IME composition.
ImeEvent Enum	IME event.
IMEOutput	Information about text being edited.
IMEPurpose Enum
InputOptions	Options for input state handling.
InputState	Input state that egui updates each frame.
InsertFontFamily	Where in the fallback chain of a `FontFamily` a `FontInsert` goes.
Interaction	How and when interaction happens.
InteractionSnapshot	Calculated at the start of each frame based on: * Widget rects from precious frame * Mouse/touch input * Current `InteractionState`.
InteractOptions	How to handle multiple calls to `egui.Response.interact` and `egui.Ui.interact_opt`.
Key Enum
KeyboardShortcut	A keyboard shortcut, e.g. `Ctrl+Alt+W`.
Label	Static text.
LabelSelectionState	Handles text selection in labels (NOT in `egui.TextEdit`)s.
LabelStyle
LayerId	An identifier for a paint layer. Also acts as an identifier for `egui.Area`:s.
Layout
LayoutJob	Describes the task of laying out text.
LayoutSection	A contiguous range of `LayoutJob.text` that shares the same `TextFormat`.
Link	Clickable text, that looks like a hyperlink.
LoadError Enum	Represents a failed attempt at loading an image.
Loaders	The loaders of bytes, images, and textures.
Margin	A value for all four sides of a rectangle, often used to express padding or spacing.
MarginF32	A value for all four sides of a rectangle, often used to express padding or spacing.
Memory	The data that egui persists between frames.
MenuBar	Horizontal menu bar where you can add `MenuButton`s.
MenuButton	A thin wrapper around a `Button` that shows a `Popup.menu` when clicked.
MenuConfig	Configuration and style for menus.
MenuResponse
MenuState	Holds the state of the menu.
Mesh	Textured triangles in two dimensions.
Mesh16	A version of `Mesh` that uses 16-bit indices.
MeshVertex
Modal	A modal dialog.
ModalResponse	The response of a modal dialog.
ModifierNames	Names of different modifier keys.
Modifiers	State of the modifier keys. These must be fed to egui.
MouseWheelUnit Enum	The unit associated with the numeric value of a mouse wheel event
MultiTouchInfo	All you probably need to know about a multi-touch gesture.
Mutable
NumberFormatter	How to format numbers in e.g. a `egui.DragValue`.
NumericColorSpace Enum	How to display numeric color values.
OpenUrl	What URL to open, and how.
OperatingSystem Enum	An `enum` of common operating systems.
Options	Some global options that you can read and write.
Order Enum	Different layer categories
OutputCommand Enum	Commands that the egui integration should execute at the end of a frame.
OutputEvent Enum	Things that happened during this frame that the integration may be interested in.
Painter	Helper to paint shapes and text to a specific region on a specific layer.
Panel	A panel that covers an entire side (`left`, `right`, `top` or `bottom`) of a `Ui` or screen.
PanelState	State regarding panels.
ParseHexColorError Enum
PathShape	A path which can be stroked and/or filled (if closed).
PathStroke	Describes the width and color of paths. The color can either be solid or provided by a callback. For more information, see `ColorMode`
PlatformOutput	The non-rendering part of what egui emits each frame.
PointerButton Enum	Mouse button (or similar for touch input)
PointerState	Mouse or touch state.
Popup	A popup container.
PopupAnchor Enum	What should we anchor the popup to?
PopupCloseBehavior Enum	Determines popup's close behavior
PopupKind Enum	Is the popup a popup, tooltip or menu?
PopupResponse
Pos2	A position on screen.
ProgressBar	A simple progress bar.
QuadraticBezierShape	A quadratic Bézier Curve.
RadioButton	One out of several alternatives, either selected or not.
Rangef	Inclusive range of floats, i.e. `min..=max`, but more ergonomic than `RangeInclusive`.
RawInput	What the integrations provides to egui at the start of each frame.
Rect	A rectangular region of space.
RectAlign
RectShape	How to paint a rectangle.
RectTransform	Linearly transforms positions from one `Rect` to another.
RepaintCause	What called `Context.request_repaint` or `Context.request_discard`?
RequestRepaintInfo	Information given to the backend about when it is time to repaint the ui.
Resize	A region that can be resized by dragging the bottom right corner.
ResizeDirection Enum
Response	The result of adding a widget to a `Ui`.
ResponseFlags
Rgba	0-1 linear space `RGBA` color with premultiplied alpha.
RichText	Text and optional style choices for it.
RowVertexIndices
Runtime
SafeAreaInsets	The 'safe area' insets of the screen
Scene	A container that allows you to zoom and pan.
ScrollAnimation	Scroll animation configuration, used when programmatically scrolling somewhere (e.g. with `[`egui.Ui.scroll_to_cursor`](egui.Ui.html#scroll_to_cursor-5999)`).
ScrollArea	Add vertical and/or horizontal scrolling to a contained `Ui`.
ScrollAreaOutput
ScrollAreaRowsUi
ScrollAreaState
ScrollAreaViewportUi
ScrollBarVisibility Enum	Indicate whether the horizontal and vertical scroll bars must be always visible, hidden or visible when needed.
ScrollFadeStyle	Controls if and how to fade out the sides of a `egui.ScrollArea` to indicate there is more there if you scroll.
ScrollSource	What is the source of scrolling for a `ScrollArea`.
ScrollStyle	Controls the spacing and visuals of a `egui.ScrollArea`.
SelectableLabel
Selection	Selected text, selected elements etc
Sense
Separator	A visual separator. A horizontal or vertical line (depending on `egui.Layout`).
SeparatorStyle	Dedicated separator style
SetOpenCommand Enum
Shadow	The color and fuzziness of a fuzzy shape.
Shape Enum	A paint primitive such as a circle or a piece of text. Coordinates are all screen space points (not physical pixels).
ShownSides
SidePanel
Sides	Put some widgets on the left and right sides of a ui.
Size Enum	Size hint for table column/strip cell.
SizedAtom	A `egui.Atom` which has been sized.
SizedAtomKind Enum	A sized `egui.AtomKind`.
SizedAtomLayout	`SizedAtomLayout` was split into `SizedWidgetAtom` (id, sense) and `SizedContainerAtom` (the measured contents). `SizedWidgetAtom` is the direct replacement.
SizedTexture	A texture with a known size.
SizeHint Enum	Given as a hint for image loading requests.
Slider	Control a number with a slider.
SliderClamping Enum	Specifies how values in a `Slider` are clamped.
SliderOrientation Enum	Specifies the orientation of a `Slider`.
SmoothHinting	Tuning for `HintingTarget.Smooth`, mirroring `skrifa`'s `Target.Smooth`.
Spacing	Controls the sizes and distances between widgets.
Spinner	A spinner widget used to indicate loading.
Strip	A Strip of cells which go in one direction. Each cell has a fixed size. In contrast to normal egui behavior, strip cells do not grow with its children!
StripBuilder	Builder for creating a new `Strip`.
Stroke	Describes the width and color of a line.
StrokeKind Enum	Describes how the stroke of a shape should be painted.
Style	Specifies the look and feel of egui.
StyleModifier	Utility to modify a `Style` in some way. Constructed via `StyleModifier.from` from a `Fn(Style)` or a `Style`.
SubMenu	Show a submenu in a menu.
SubMenuButton	A submenu button that shows a `SubMenu` if a `Button` is hovered.
SurrenderFocusOn Enum
SvgLoader
SystemTheme Enum
Table	Table struct which can construct a `TableBody`.
TableBody	The body of a table.
TableBuilder	Builder for a `Table` with (optional) fixed header and scrolling body.
TableHeader
TableRow	The row of a table. Is created by `TableRow` for each created `TableBody.row` or each visible row in rows created by calling `TableBody.rows`.
TableRows
TessellationOptions	Tessellation quality options
Tessellator	Converts `Shape`s into triangles (`Mesh`).
TextBuffer
TextCursorState	The state of a text cursor selection.
TextCursorStyle	Look and feel of the text cursor.
TextEdit	A text region that the user can edit the contents of.
TextEditOutput	The output from a `TextEdit`.
TextEditState	The text edit state stored between frames.
TextEditUndoer
TextFormat	Formatting option for a section of text.
TextLayouter
TextOptions	Controls how we render text
TextShape	How to paint some text on screen.
TextStyle Enum	Alias for a `FontId` (font of a certain size).
TextStyles
TextureFilter Enum	How the texture texels are filtered.
TextureHandle	Used to paint images.
TextureId Enum	What texture to use in a `Mesh` mesh.
TextureLoader
TextureOptions	How the texture texels are filtered.
TexturePoll Enum	Represents a texture is currently being loaded.
TexturesDelta	What has been allocated and freed during the last period.
TextureWrapMode Enum	Defines how textures are wrapped around objects when texture coordinates fall outside the [0, 1] range.
TextVisuals	General text style
TextWrapMode Enum	How to wrap and elide text.
TextWrapping	Controls the text wrapping and elision of a `LayoutJob`.
Theme Enum	Dark or Light theme.
ThemePreference Enum	The user's theme preference.
Tooltip
TopBottomPanel
TouchDeviceId	this is a `int` as values of this kind can always be obtained by hashing
TouchId	Unique identification of a touch occurrence (finger or pen or …). A Touch ID is valid until the finger is lifted. A new ID is used for the next touch.
TouchPhase Enum	In what phase a touch event is in.
TSTransform	Linearly transforms positions via a translation, then a scaling.
Ui	This is what you use to place widgets.
UiBuilder	The properties specified when creating a top-level or child `Ui`.
UiKind Enum	What kind is this `egui.Ui`?
UiStack	Information about a `egui.Ui` and its parents.
UiStackInfo	Information about a `egui.Ui` to be included in the corresponding `UiStack`.
Undoer	Automatic undo system.
UndoSettings
UserAttentionType Enum	Types of attention to request from a user when a native window is not in focus.
UserData
Vec2	A vector has a direction and length. A `Vec2` is often used to represent a size.
Vec2b	Two bools, one for each axis (X and Y).
ViewportBuilder	Control the building of a new egui viewport (i.e. native window).
ViewportClass Enum	The different types of viewports supported by egui.
ViewportCommand Enum	An output viewport-command from egui to the backend, e.g. to change the window title or size.
ViewportEvent Enum	An input event from the backend into egui, about a specific viewport.
ViewportId	A unique identifier of a viewport.
ViewportIdPair	A pair of `ViewportId`, used to identify a viewport and its parent.
ViewportInfo	Information about the current viewport, given as input each frame.
ViewportOutput	Describes a viewport, i.e. a native window.
ViewportUi
Visuals	Controls the visual style (colors etc) of egui.
WidgetInfo	Describes a widget such as a `egui.Button` or a `egui.TextEdit`.
WidgetRect	Used to store each widget's `Id`, `Rect` and `Sense` each frame.
WidgetRects	Stores the `WidgetRect`s of all widgets generated during a single egui update/frame.
Widgets	The visuals of widgets for different states of interaction.
WidgetState Enum	The different state of a widget can be
WidgetStyle
WidgetText Enum	This is how you specify text for a widget.
WidgetType Enum	The different types of built-in widgets in egui
WidgetVisuals	bg = background, fg = foreground.
Window	Builder for a floating window which can be dragged, closed, collapsed, resized and scrolled (off by default).
Window
WindowDrag Enum	Where the user can drag to move a `Window`.
WindowLevel Enum	For winit platform compatibility, see `winit.WindowLevel` documentation
X11WindowType Enum

Functions§

accesskit_root_id
at_least
at_most
bar
byte_index_from_char_index
capture	Capture a callstack, skipping the frames that are not interesting.
capture_callstack
ccursor_next_word
ccursor_previous_word
char_index_from_byte_index
code_view_ui	View some code with syntax highlighting and selection.
color_edit_button_hsva
color_edit_button_rgb	Shows a button with the given color. If the user clicks the button, a full color picker is shown.
color_edit_button_rgba	Shows a button with the given color. If the user clicks the button, a full color picker is shown.
color_edit_button_srgb	Shows a button with the given color. If the user clicks the button, a full color picker is shown. The given color is in `sRGB` space.
color_edit_button_srgba	Shows a button with the given color. If the user clicks the button, a full color picker is shown.
color_picker_color32	Shows a color picker where the user can change the given `Color32` color.
color_picker_hsva_2d	Shows a color picker where the user can change the given `Hsva` color.
context_menu
context_menu_opened
cursor_rect	The thin rectangle of one end of the selection, e.g. the primary cursor, in local galley coordinates.
debug_print
debug_print_str
decode_animated_image_uri	Extracts uri and frame index Errors Will return `Err` if `uri` does not match pattern {uri}-{frame_index}
default_text_styles	The default text styles of the default egui theme.
find_line_start	Accepts and returns character offset (NOT byte offset!).
find_menu_root	Find the root `UiStack` of the menu.
font_family_ui
font_id_ui
global_dark_light_mode_buttons
global_dark_light_mode_switch
global_theme_preference_buttons	Show a row of buttons for changing the theme of the whole app.
global_theme_preference_switch	Show a small button to switch to/from dark/light mode (globally).
has_gif_magic_header	Checks if bytes are gifs
has_webp_header	Checks if bytes are webp
highlight	Add syntax highlighting to a code string.
install_image_loaders	Installs a set of image loaders.
is_in_menu	Is this Ui part of a menu?
is_word_char
layouter
lerp	Linear interpolation.
load_svg_bytes	Load an SVG and rasterize it into an egui image.
load_svg_bytes_with_size	Load an SVG and rasterize it into an egui image with a scaling parameter.
loaders_ui
menu_button
menu_custom_button
menu_image_button
menu_style	Apply a menu style to the `Style`.
paint_cursor_end	Paint one end of the selection, e.g. the primary cursor.
paint_default_icon	Paint the arrow icon that indicated if the region is open or not
paint_resize_corner
paint_resize_corner_with_style
paint_text_cursor	Paint one end of the selection, e.g. the primary cursor, with blinking (if enabled).
paint_text_selection	Adds text selection rectangles to the galley.
paint_texture_at
paint_texture_load_result
pos2	`pos2(x, y) == Pos2.new(x, y)`
print	Print this text next to the cursor at the end of the pass.
remap	Linearly remap a value from one range to another, so that when `x == from.start()` returns `to.start()` and when `x == from.end()` returns `to.end()`.
remap_clamp	Like `remap`, but also clamps the value so that the returned value is always in the `to` range.
render
reset_button	Show a button to reset a value to its default. The button is only enabled if the value does not already have its original value.
reset_button_with	Show a button to reset a value to its default. The button is only enabled if the value does not already have its original value.
show_color	Show a color with background checkers to demonstrate transparency (if any).
show_color_at	Show a color with background checkers to demonstrate transparency (if any).
show_tooltip_text
slice_char_range
stroke_ui
submenu_button
texture_load_result_response	Attach tooltips like "Loading…" or "Failed loading: …".
vec2	`vec2(x, y) == Vec2.new(x, y)`
warn_if_debug_build	Helper function that adds a label when compiling with debug assertions enabled.
was_tooltip_open_last_frame
zoom_in	Make everything larger by increasing `Context.zoom_factor`.
zoom_menu_buttons	Show buttons for zooming the ui.
zoom_out	Make everything smaller by decreasing `Context.zoom_factor`.

SourceFunction `accesskit_root_id`§

from egui import accesskit_root_id

def accesskit_root_id() -> Id

Function `at_least`§

from egui import at_least

def at_least(value: float, lower_limit: float) -> float

Function `at_most`§

from egui import at_most

def at_most(value: float, upper_limit: float) -> float

Function `bar`§

from egui import bar

def bar() -> Any

SourceFunction `byte_index_from_char_index`§

from egui import byte_index_from_char_index

def byte_index_from_char_index(s: str, char_index: int) -> int

SourceFunction `capture`§

from egui import capture

def capture() -> str

Capture a callstack, skipping the frames that are not interesting.

In particular: slips everything before egui.Context.run, and skipping all frames in the egui. namespace.

Function `capture_callstack`§

from egui import capture_callstack

def capture_callstack() -> str

SourceFunction `ccursor_next_word`§

from egui import ccursor_next_word

def ccursor_next_word(text: str, ccursor: CCursor) -> CCursor

SourceFunction `ccursor_previous_word`§

from egui import ccursor_previous_word

def ccursor_previous_word(text: str, ccursor: CCursor) -> CCursor

SourceFunction `char_index_from_byte_index`§

from egui import char_index_from_byte_index

def char_index_from_byte_index(input: str, byte_index: int) -> int

SourceFunction `code_view_ui`§

from egui.syntax_highlighting import code_view_ui

def code_view_ui(ui: Ui, theme: CodeTheme, code: str, language: str) -> Response

View some code with syntax highlighting and selection.

SourceFunction `color_edit_button_hsva`§

from egui import color_edit_button_hsva

def color_edit_button_hsva(ui: Ui, hsva: Hsva, alpha: Alpha) -> Response

SourceFunction `color_edit_button_rgb`§

from egui import color_edit_button_rgb

def color_edit_button_rgb(ui: Ui, rgb: Mutable) -> Response

Shows a button with the given color. If the user clicks the button, a full color picker is shown.

SourceFunction `color_edit_button_rgba`§

from egui import color_edit_button_rgba

def color_edit_button_rgba(ui: Ui, rgba: Rgba, alpha: Alpha) -> Response

Shows a button with the given color. If the user clicks the button, a full color picker is shown.

SourceFunction `color_edit_button_srgb`§

from egui import color_edit_button_srgb

def color_edit_button_srgb(ui: Ui, srgb: Mutable) -> Response

Shows a button with the given color. If the user clicks the button, a full color picker is shown. The given color is in sRGB space.

SourceFunction `color_edit_button_srgba`§

from egui import color_edit_button_srgba

def color_edit_button_srgba(ui: Ui, srgba: Color32, alpha: Alpha) -> Response

Shows a button with the given color. If the user clicks the button, a full color picker is shown.

SourceFunction `color_picker_color32`§

from egui import color_picker_color32

def color_picker_color32(ui: Ui, srgba: Color32, alpha: Alpha) -> bool

Shows a color picker where the user can change the given Color32 color.

Returns True on change.

SourceFunction `color_picker_hsva_2d`§

from egui import color_picker_hsva_2d

def color_picker_hsva_2d(ui: Ui, hsva: Hsva, alpha: Alpha) -> bool

Shows a color picker where the user can change the given Hsva color.

Returns True on change.

Function `context_menu`§

from egui import context_menu

def context_menu(response: Response) -> Any

Function `context_menu_opened`§

from egui import context_menu_opened

def context_menu_opened(response: Response) -> bool

SourceFunction `cursor_rect`§

from egui import cursor_rect

def cursor_rect(galley: Galley, cursor: CCursor, row_height: float) -> Rect

The thin rectangle of one end of the selection, e.g. the primary cursor, in local galley coordinates.

Function `debug_print`§

from egui import debug_print

def debug_print(ctx: Context, text: WidgetText) -> None

Function `debug_print_str`§

from egui import debug_print_str

def debug_print_str(ctx: Context, text: str) -> None

SourceFunction `decode_animated_image_uri`§

from egui import decode_animated_image_uri

def decode_animated_image_uri(uri: str) -> tuple[str, int]

Extracts uri and frame index

Errors

Will return Err if uri does not match pattern {uri}-{frame_index}

SourceFunction `default_text_styles`§

from egui import default_text_styles

def default_text_styles() -> TextStyles

The default text styles of the default egui theme.

SourceFunction `find_line_start`§

from egui import find_line_start

def find_line_start(text: str, current_index: CCursor) -> CCursor

Accepts and returns character offset (NOT byte offset!).

SourceFunction `find_menu_root`§

from egui import find_menu_root

def find_menu_root(ui: Ui) -> UiStack

Find the root UiStack of the menu.

SourceFunction `font_family_ui`§

from egui import font_family_ui

def font_family_ui(ui: Ui, font_family: FontFamily) -> None

SourceFunction `font_id_ui`§

from egui import font_id_ui

def font_id_ui(ui: Ui, font_id: FontId) -> None

Function `global_dark_light_mode_buttons`§

from egui import global_dark_light_mode_buttons

def global_dark_light_mode_buttons(ui: Ui) -> None

Function `global_dark_light_mode_switch`§

from egui import global_dark_light_mode_switch

def global_dark_light_mode_switch(ui: Ui) -> None

SourceFunction `global_theme_preference_buttons`§

from egui import global_theme_preference_buttons

def global_theme_preference_buttons(ui: Ui) -> None

Show a row of buttons for changing the theme of the whole app.

There is one button for each egui.ThemePreference: dark mode, light mode, and following the system theme. The button of the current preference is highlighted.

Each button is a small icon, so this fits in a top bar.

SourceFunction `global_theme_preference_switch`§

from egui import global_theme_preference_switch

def global_theme_preference_switch(ui: Ui) -> None

Show a small button to switch to/from dark/light mode (globally).

This does not allow switching back to following the system theme, which is why global_theme_preference_buttons is preferred.

SourceFunction `has_gif_magic_header`§

from egui import has_gif_magic_header

def has_gif_magic_header(bytes: Any) -> bool

Checks if bytes are gifs

SourceFunction `has_webp_header`§

from egui import has_webp_header

def has_webp_header(bytes: Any) -> bool

Checks if bytes are webp

SourceFunction `highlight`§

from egui.syntax_highlighting import highlight

def highlight(ctx: Context, style: Style, theme: CodeTheme, code: str, language: str) -> LayoutJob

Add syntax highlighting to a code string.

The results are memoized, so you can call this every frame without performance penalty.

SourceFunction `install_image_loaders`§

from egui import install_image_loaders

def install_image_loaders(ctx: Context) -> None

Installs a set of image loaders.

Calling this enables the use of egui.Image and egui.Ui.image.

⚠ This will do nothing and you won't see any images unless you also enable some feature flags on egui_extras:

file feature: file:// loader on non-Wasm targets
http feature: http(s):// loader
image feature: Loader of png, jpeg etc using the image crate
svg feature: .svg loader

Calling this multiple times on the same egui.Context is safe. It will never install duplicate loaders.

If you just want to be able to load file:// and http:// URIs, enable the all_loaders feature.
The supported set of image formats is configured by adding the image crate as your direct dependency, and enabling features on it:

⚠ You have to configure both the supported loaders in egui_extras and the supported image formats in image to get any output!

Loader-specific information

⚠ The exact way bytes, images, and textures are loaded is subject to change, but the supported protocols and file extensions are not.

The file loader is a BytesLoaderegui.load.BytesLoader. It will attempt to load file:// URIs, and infer the content type from the extension. The path will be passed to std.fs.read after trimming the file:// prefix, and is resolved the same way as with std.fs.read(path): - Relative paths are relative to the current working directory - Absolute paths are left as is.

The http loader is a BytesLoaderegui.load.BytesLoader. It will attempt to load http:// and https:// URIs, and infer the content type from the Content-Type header.

The image loader is an ImageLoaderegui.load.ImageLoader. It will attempt to load any URI with any extension other than svg. It will also try to load any URI without an extension. The content type specified by BytesPoll.Ready.mimeegui.load.BytesPoll.Ready.mime always takes precedence. This means that even if the URI has a png extension, and the png image format is enabled, if the content type is not one of the supported and enabled image formats, the loader will return LoadError.NotSupportedegui.load.LoadError.NotSupported, allowing a different loader to attempt to load the image.

The svg loader is an ImageLoaderegui.load.ImageLoader. It will attempt to load any URI with an svg extension. It will not attempt to load a URI without an extension. The content type specified by BytesPoll.Ready.mimeegui.load.BytesPoll.Ready.mime always takes precedence, and must include svg for it to be considered supported. For example, image/svg+xml would be loaded by the svg loader.

See egui.load for more information about how loaders work.

SourceFunction `is_in_menu`§

from egui import is_in_menu

def is_in_menu(ui: Ui) -> bool

Is this Ui part of a menu?

Returns False if this is a menu bar. Should be used to determine if we should show a menu button or submenu button.

SourceFunction `is_word_char`§

from egui import is_word_char

def is_word_char(c: str) -> bool

Function `layouter`§

from egui.syntax_highlighting import layouter

def layouter(theme: CodeTheme, language: str) -> TextLayouter

SourceFunction `lerp`§

from egui import lerp

def lerp(min: float, max: float, t: float) -> float

Linear interpolation.

SourceFunction `load_svg_bytes`§

from egui import load_svg_bytes

def load_svg_bytes(svg_bytes: Sequence[int]) -> ColorImage

Load an SVG and rasterize it into an egui image.

Requires the "svg" feature.

Errors

On invalid image

SourceFunction `load_svg_bytes_with_size`§

from egui import load_svg_bytes_with_size

def load_svg_bytes_with_size(svg_bytes: Sequence[int], size_hint: SizeHint) -> ColorImage

Load an SVG and rasterize it into an egui image with a scaling parameter.

Requires the "svg" feature.

Errors

On invalid image

Function `loaders_ui`§

from egui import loaders_ui

def loaders_ui(ctx: Context, ui: Ui) -> None

Function `menu_button`§

from egui import menu_button

def menu_button(title: Any) -> Any

Function `menu_custom_button`§

from egui import menu_custom_button

def menu_custom_button(button: Button) -> Any

Function `menu_image_button`§

from egui import menu_image_button

def menu_image_button(image_uri: str, title: str) -> Any

SourceFunction `menu_style`§

from egui import menu_style

def menu_style(style: Style) -> None

Apply a menu style to the Style.

Mainly removes the background stroke and the inactive background fill.

SourceFunction `paint_cursor_end`§

from egui import paint_cursor_end

def paint_cursor_end(painter: Painter, visuals: Visuals, cursor_rect: Rect) -> None

Paint one end of the selection, e.g. the primary cursor.

This will never blink.

SourceFunction `paint_default_icon`§

from egui import paint_default_icon

def paint_default_icon(ui: Ui, openness: float, response: Response) -> None

Paint the arrow icon that indicated if the region is open or not

SourceFunction `paint_resize_corner`§

from egui import paint_resize_corner

def paint_resize_corner(ui: Ui, response: Response) -> None

SourceFunction `paint_resize_corner_with_style`§

from egui import paint_resize_corner_with_style

def paint_resize_corner_with_style(ui: Ui, rect: Rect, color: Color32, corner: Align2) -> None

SourceFunction `paint_text_cursor`§

from egui import paint_text_cursor

def paint_text_cursor(ui: Ui, painter: Painter, primary_cursor_rect: Rect, time_since_last_interaction: float) -> None

Paint one end of the selection, e.g. the primary cursor, with blinking (if enabled).

SourceFunction `paint_text_selection`§

from egui import paint_text_selection

def paint_text_selection(galley: Galley, visuals: Visuals, cursor_range: CCursorRange, collect_new_vertex_indices: bool = False) -> list[RowVertexIndices] |None

Adds text selection rectangles to the galley.

SourceFunction `paint_texture_at`§

from egui import paint_texture_at

def paint_texture_at(painter: Painter, rect: Rect, options: ImageOptions, texture: SizedTexture) -> None

SourceFunction `paint_texture_load_result`§

from egui import paint_texture_load_result

def paint_texture_load_result(ui: Ui, rect: Rect, options: ImageOptions, texture_poll: TexturePoll |None = None, error: LoadError |None = None, show_loading_spinner: bool |None = None, alt_text: str |None = None) -> None

SourceFunction `pos2`§

from egui import pos2

def pos2(x: float, y: float) -> Pos2

pos2(x, y) == Pos2.new(x, y)

SourceFunction `print`§

from egui import print

def print(ctx: Context, text: Any) -> None

Print this text next to the cursor at the end of the pass.

If you call this multiple times, the text will be appended.

This only works if compiled with debug_assertions.

SourceFunction `remap`§

from egui import remap

def remap(x: float, from_min: float, from_max: float, to_min: float, to_max: float) -> float

Linearly remap a value from one range to another, so that when x == from.start() returns to.start() and when x == from.end() returns to.end().

SourceFunction `remap_clamp`§

from egui import remap_clamp

def remap_clamp(x: float, from_min: float, from_max: float, to_min: float, to_max: float) -> float

Like remap, but also clamps the value so that the returned value is always in the to range.

Function `render`§

from egui import render

def render(callback: Any, ui: Ui) -> None

SourceFunction `reset_button`§

from egui import reset_button

def reset_button(ui: Ui, value: Mutable, text: str) -> None

Show a button to reset a value to its default. The button is only enabled if the value does not already have its original value.

The text could be something like "Reset foo".

SourceFunction `reset_button_with`§

from egui import reset_button_with

def reset_button_with(ui: Ui, value: Mutable, text: str, reset_value: Any) -> None

Show a button to reset a value to its default. The button is only enabled if the value does not already have its original value.

The text could be something like "Reset foo".

SourceFunction `show_color`§

from egui import show_color

def show_color(ui: Ui, color: Color32, desired_size: Vec2) -> Response

Show a color with background checkers to demonstrate transparency (if any).

SourceFunction `show_color_at`§

from egui import show_color_at

def show_color_at(painter: Painter, color: Color32, rect: Rect) -> None

Show a color with background checkers to demonstrate transparency (if any).

Function `show_tooltip_text`§

from egui import show_tooltip_text

def show_tooltip_text(ctx: Context, parent_layer: LayerId, widget_id: Id, text: WidgetText) -> bool

SourceFunction `slice_char_range`§

from egui import slice_char_range

def slice_char_range(s: str, start: int, end: int) -> str

Function `stroke_ui`§

from egui import stroke_ui

def stroke_ui(ui: Ui, stroke: Stroke, text: str) -> None

Function `submenu_button`§

from egui import submenu_button

def submenu_button(title: Any) -> Any

SourceFunction `texture_load_result_response`§

from egui import texture_load_result_response

def texture_load_result_response(source: ImageSource, response: Response, texture_poll: TexturePoll |None = None, error: LoadError |None = None) -> Response

Attach tooltips like "Loading…" or "Failed loading: …".

SourceFunction `vec2`§

from egui import vec2

def vec2(x: float, y: float) -> Vec2

vec2(x, y) == Vec2.new(x, y)

SourceFunction `warn_if_debug_build`§

from egui import warn_if_debug_build

def warn_if_debug_build(ui: Ui) -> None

Helper function that adds a label when compiling with debug assertions enabled.

Function `was_tooltip_open_last_frame`§

from egui import was_tooltip_open_last_frame

def was_tooltip_open_last_frame(ctx: Context, widget_id: Id) -> bool

SourceFunction `zoom_in`§

from egui import zoom_in

def zoom_in(ctx: Context) -> None

Make everything larger by increasing Context.zoom_factor.

SourceFunction `zoom_menu_buttons`§

from egui import zoom_menu_buttons

def zoom_menu_buttons(ui: Ui) -> None

Show buttons for zooming the ui.

This is meant to be called from within a menu (See Ui.menu_button).

SourceFunction `zoom_out`§

from egui import zoom_out

def zoom_out(ctx: Context) -> None

Make everything smaller by decreasing Context.zoom_factor.

Constants§

RenderHtmlFn
RenderMathFn
SkipUiBlock

SourceModule egui

Using egui§

A simple example§

Quick start§

Coordinate system§

Understanding immediate mode§

Multi-pass immediate mode§

Misc§

Widget interaction§

Installing additional fonts§

Modules§

Classes§

Functions§

Errors

SourceFunction accesskit_root_id§

Function at_least§

Function at_most§

Function bar§

SourceFunction byte_index_from_char_index§

SourceFunction capture§

Function capture_callstack§

SourceFunction ccursor_next_word§

SourceFunction ccursor_previous_word§

SourceFunction char_index_from_byte_index§

SourceFunction code_view_ui§

SourceFunction color_edit_button_hsva§

SourceFunction color_edit_button_rgb§

SourceFunction color_edit_button_rgba§

SourceFunction color_edit_button_srgb§

SourceFunction color_edit_button_srgba§

SourceFunction color_picker_color32§

SourceFunction color_picker_hsva_2d§

Function context_menu§

Function context_menu_opened§

SourceFunction cursor_rect§

Function debug_print§

Function debug_print_str§

SourceFunction decode_animated_image_uri§

Errors

SourceFunction default_text_styles§

SourceFunction find_line_start§

SourceFunction find_menu_root§

SourceFunction font_family_ui§

SourceFunction font_id_ui§

Function global_dark_light_mode_buttons§

Function global_dark_light_mode_switch§

SourceFunction global_theme_preference_buttons§

SourceFunction global_theme_preference_switch§

SourceFunction has_gif_magic_header§

SourceFunction has_webp_header§

SourceFunction highlight§

SourceFunction install_image_loaders§

Loader-specific information

SourceFunction is_in_menu§

SourceFunction is_word_char§

Function layouter§

SourceFunction lerp§

SourceFunction load_svg_bytes§

Errors

SourceFunction load_svg_bytes_with_size§

Errors

Function loaders_ui§

Function menu_button§

Function menu_custom_button§

Function menu_image_button§

SourceFunction menu_style§

SourceFunction paint_cursor_end§

SourceFunction paint_default_icon§

SourceFunction paint_resize_corner§

SourceFunction paint_resize_corner_with_style§

SourceFunction paint_text_cursor§

SourceFunction paint_text_selection§

SourceFunction paint_texture_at§

SourceFunction paint_texture_load_result§

SourceFunction pos2§

SourceFunction print§

SourceFunction remap§

SourceFunction remap_clamp§

Function render§

SourceFunction reset_button§

SourceFunction `accesskit_root_id`§

Function `at_least`§

Function `at_most`§

Function `bar`§

SourceFunction `byte_index_from_char_index`§

SourceFunction `capture`§

Function `capture_callstack`§

SourceFunction `ccursor_next_word`§

SourceFunction `ccursor_previous_word`§

SourceFunction `char_index_from_byte_index`§

SourceFunction `code_view_ui`§

SourceFunction `color_edit_button_hsva`§

SourceFunction `color_edit_button_rgb`§

SourceFunction `color_edit_button_rgba`§

SourceFunction `color_edit_button_srgb`§

SourceFunction `color_edit_button_srgba`§

SourceFunction `color_picker_color32`§

SourceFunction `color_picker_hsva_2d`§

Function `context_menu`§

Function `context_menu_opened`§

SourceFunction `cursor_rect`§

Function `debug_print`§

Function `debug_print_str`§

SourceFunction `decode_animated_image_uri`§

SourceFunction `default_text_styles`§

SourceFunction `find_line_start`§

SourceFunction `find_menu_root`§

SourceFunction `font_family_ui`§

SourceFunction `font_id_ui`§

Function `global_dark_light_mode_buttons`§

Function `global_dark_light_mode_switch`§

SourceFunction `global_theme_preference_buttons`§

SourceFunction `global_theme_preference_switch`§

SourceFunction `has_gif_magic_header`§

SourceFunction `has_webp_header`§

SourceFunction `highlight`§

SourceFunction `install_image_loaders`§

SourceFunction `is_in_menu`§

SourceFunction `is_word_char`§

Function `layouter`§

SourceFunction `lerp`§

SourceFunction `load_svg_bytes`§

SourceFunction `load_svg_bytes_with_size`§

Function `loaders_ui`§

Function `menu_button`§

Function `menu_custom_button`§

Function `menu_image_button`§

SourceFunction `menu_style`§

SourceFunction `paint_cursor_end`§

SourceFunction `paint_default_icon`§

SourceFunction `paint_resize_corner`§

SourceFunction `paint_resize_corner_with_style`§

SourceFunction `paint_text_cursor`§

SourceFunction `paint_text_selection`§

SourceFunction `paint_texture_at`§

SourceFunction `paint_texture_load_result`§

SourceFunction `pos2`§

SourceFunction `print`§

SourceFunction `remap`§

SourceFunction `remap_clamp`§

Function `render`§

SourceFunction `reset_button`§

SourceFunction `reset_button_with`§

SourceFunction `show_color`§

SourceFunction `show_color_at`§

Function `show_tooltip_text`§

SourceFunction `slice_char_range`§

Function `stroke_ui`§

Function `submenu_button`§

SourceFunction `texture_load_result_response`§

SourceFunction `vec2`§

SourceFunction `warn_if_debug_build`§

Function `was_tooltip_open_last_frame`§

SourceFunction `zoom_in`§

SourceFunction `zoom_menu_buttons`§

SourceFunction `zoom_out`§