> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/ocornut/imgui/llms.txt
> Use this file to discover all available pages before exploring further.

# ImGuiIO Structure

> Main configuration and I/O structure for Dear ImGui

## Overview

The `ImGuiIO` structure is the main configuration and I/O interface between your application and Dear ImGui. It contains:

* Configuration options and flags
* Input state (mouse, keyboard, gamepad)
* Output flags (WantCaptureMouse, WantCaptureKeyboard, etc.)
* Time and framerate information

## Getting ImGuiIO

```cpp theme={null}
ImGuiIO& io = ImGui::GetIO();
```

See [GetIO](/api/input#getio) for details.

## Configuration Fields

### Display Configuration

<ResponseField name="DisplaySize" type="ImVec2">
  Main display size in pixels. May change every frame.
</ResponseField>

<ResponseField name="DisplayFramebufferScale" type="ImVec2" default="(1, 1)">
  For retina displays where window coordinates differ from framebuffer coordinates. Affects font density.
</ResponseField>

<ResponseField name="DeltaTime" type="float" default="1.0f/60.0f">
  Time elapsed since last frame, in seconds. May change every frame.
</ResponseField>

**Example:**

```cpp theme={null}
ImGuiIO& io = ImGui::GetIO();
io.DisplaySize = ImVec2(1920.0f, 1080.0f);
io.DisplayFramebufferScale = ImVec2(2.0f, 2.0f); // Retina
io.DeltaTime = 1.0f / 60.0f;
```

### Configuration Flags

<ResponseField name="ConfigFlags" type="ImGuiConfigFlags" default="0">
  See `ImGuiConfigFlags_` enum. Set by user/application.
</ResponseField>

<ResponseField name="BackendFlags" type="ImGuiBackendFlags" default="0">
  See `ImGuiBackendFlags_` enum. Set by backend to communicate features supported.
</ResponseField>

```cpp theme={null}
enum ImGuiConfigFlags_
{
    ImGuiConfigFlags_None                   = 0,
    ImGuiConfigFlags_NavEnableKeyboard      = 1 << 0,   // Enable keyboard navigation
    ImGuiConfigFlags_NavEnableGamepad       = 1 << 1,   // Enable gamepad navigation
    ImGuiConfigFlags_NoMouse                = 1 << 4,   // Disable mouse inputs
    ImGuiConfigFlags_NoMouseCursorChange    = 1 << 5,   // Don't alter mouse cursor
    ImGuiConfigFlags_NoKeyboard             = 1 << 6,   // Disable keyboard inputs
    ImGuiConfigFlags_IsSRGB                 = 1 << 20,  // Application is SRGB-aware
    ImGuiConfigFlags_IsTouchScreen          = 1 << 21,  // Using touch screen
};
```

**Example:**

```cpp theme={null}
ImGuiIO& io = ImGui::GetIO();
io.ConfigFlags |= ImGuiConfigFlags_NavEnableKeyboard;
io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad;
```

### Font Configuration

<ResponseField name="Fonts" type="ImFontAtlas*">
  Font atlas: load, rasterize and pack fonts into a single texture.
</ResponseField>

<ResponseField name="FontDefault" type="ImFont*" default="NULL">
  Font to use on NewFrame(). NULL uses Fonts->Fonts\[0].
</ResponseField>

<ResponseField name="FontAllowUserScaling" type="bool" default="false">
  Allow user scaling text with Ctrl+Wheel.
</ResponseField>

### File Paths

<ResponseField name="IniFilename" type="const char*" default="imgui.ini">
  Path to .ini file for saving/loading settings. Set NULL to disable.
</ResponseField>

<ResponseField name="LogFilename" type="const char*" default="imgui_log.txt">
  Path to .log file (default for LogToFile when no file specified).
</ResponseField>

<Warning>
  Default "imgui.ini" is relative to current working directory! Most apps should lock this to an absolute path.
</Warning>

### Timing Configuration

<ResponseField name="IniSavingRate" type="float" default="5.0f">
  Minimum time between saving positions/sizes to .ini file, in seconds.
</ResponseField>

<ResponseField name="MouseDoubleClickTime" type="float" default="0.30f">
  Time for a double-click, in seconds.
</ResponseField>

<ResponseField name="MouseDoubleClickMaxDist" type="float" default="6.0f">
  Distance threshold to stay in to validate a double-click, in pixels.
</ResponseField>

<ResponseField name="MouseDragThreshold" type="float" default="6.0f">
  Distance threshold before considering we are dragging.
</ResponseField>

<ResponseField name="KeyRepeatDelay" type="float" default="0.275f">
  When holding a key/button, time before it starts repeating, in seconds.
</ResponseField>

<ResponseField name="KeyRepeatRate" type="float" default="0.050f">
  When holding a key/button, rate at which it repeats, in seconds.
</ResponseField>

### Navigation Configuration

<ResponseField name="ConfigNavSwapGamepadButtons" type="bool" default="false">
  Swap Activate/Cancel (A/B) buttons, matching Nintendo/Japanese style.
</ResponseField>

<ResponseField name="ConfigNavMoveSetMousePos" type="bool" default="false">
  Directional/tabbing navigation teleports the mouse cursor.
</ResponseField>

<ResponseField name="ConfigNavCaptureKeyboard" type="bool" default="true">
  Sets io.WantCaptureKeyboard when io.NavActive is set.
</ResponseField>

<ResponseField name="ConfigNavEscapeClearFocusItem" type="bool" default="true">
  Pressing Escape can clear focused item + navigation.
</ResponseField>

<ResponseField name="ConfigNavCursorVisibleAuto" type="bool" default="true">
  Using directional navigation key makes the cursor visible.
</ResponseField>

### Miscellaneous Configuration

<ResponseField name="MouseDrawCursor" type="bool" default="false">
  Request ImGui to draw a mouse cursor for you (software cursor).
</ResponseField>

<ResponseField name="ConfigMacOSXBehaviors" type="bool" default="defined(__APPLE__)">
  Swap Cmd/Ctrl keys + OS X style text editing, etc.
</ResponseField>

<ResponseField name="ConfigInputTextCursorBlink" type="bool" default="true">
  Enable blinking cursor in InputText.
</ResponseField>

<ResponseField name="ConfigInputTextEnterKeepActive" type="bool" default="false">
  \[BETA] Pressing Enter keeps item active and selects contents.
</ResponseField>

<ResponseField name="ConfigDragClickToInputText" type="bool" default="false">
  \[BETA] Enable turning DragXXX widgets into text input with a simple click-release.
</ResponseField>

<ResponseField name="ConfigWindowsResizeFromEdges" type="bool" default="true">
  Enable resizing windows from their edges and lower-left corner.
</ResponseField>

<ResponseField name="ConfigWindowsMoveFromTitleBarOnly" type="bool" default="false">
  Only allow moving windows when clicking on their title bar.
</ResponseField>

<ResponseField name="ConfigMemoryCompactTimer" type="float" default="60.0f">
  Timer (in seconds) to free transient windows/tables memory buffers when unused. Set to -1.0f to disable.
</ResponseField>

## Output Flags

<Tip>
  When reading these flags to dispatch your inputs, it is generally easier to use their state **BEFORE** calling NewFrame().
</Tip>

<ResponseField name="WantCaptureMouse" type="bool">
  Set when Dear ImGui will use mouse inputs. Don't dispatch mouse to your game when true.
</ResponseField>

<ResponseField name="WantCaptureKeyboard" type="bool">
  Set when Dear ImGui will use keyboard inputs. Don't dispatch keyboard to your game when true.
</ResponseField>

<ResponseField name="WantTextInput" type="bool">
  Mobile/console: when set, you may display an on-screen keyboard.
</ResponseField>

<ResponseField name="WantSetMousePos" type="bool">
  MousePos has been altered, backend should reposition mouse. Rarely used!
</ResponseField>

<ResponseField name="WantSaveIniSettings" type="bool">
  When manual .ini save is active (io.IniFilename == NULL), this notifies you to save. Clear this flag yourself after saving!
</ResponseField>

<ResponseField name="NavActive" type="bool">
  Keyboard/Gamepad navigation is currently allowed.
</ResponseField>

<ResponseField name="NavVisible" type="bool">
  Keyboard/Gamepad navigation highlight is visible and allowed.
</ResponseField>

<ResponseField name="Framerate" type="float">
  Estimate of application framerate (rolling average), in frames per second.
</ResponseField>

**Example:**

```cpp theme={null}
ImGuiIO& io = ImGui::GetIO();

// Before NewFrame()
if (!io.WantCaptureMouse)
    ProcessGameMouseInput();

if (!io.WantCaptureKeyboard)
    ProcessGameKeyboardInput();

ImGui::NewFrame();
// ... ImGui code ...
```

## Input State

<Note>
  Backends should use `AddXXXEvent()` functions to submit input. These fields are maintained by ImGui.
</Note>

### Mouse State

<ResponseField name="MousePos" type="ImVec2">
  Mouse position in pixels. Set to `ImVec2(-FLT_MAX, -FLT_MAX)` if unavailable.
</ResponseField>

<ResponseField name="MouseDown" type="bool[5]">
  Mouse buttons state (0=left, 1=right, 2=middle + extras).
</ResponseField>

<ResponseField name="MouseWheel" type="float">
  Mouse wheel vertical: 1 unit scrolls about 5 lines.
</ResponseField>

<ResponseField name="MouseWheelH" type="float">
  Mouse wheel horizontal.
</ResponseField>

<ResponseField name="MouseSource" type="ImGuiMouseSource">
  Mouse actual input peripheral (Mouse/TouchScreen/Pen).
</ResponseField>

### Keyboard State

<ResponseField name="KeyCtrl" type="bool">
  Keyboard modifier down: Ctrl (non-macOS), Cmd (macOS).
</ResponseField>

<ResponseField name="KeyShift" type="bool">
  Keyboard modifier down: Shift.
</ResponseField>

<ResponseField name="KeyAlt" type="bool">
  Keyboard modifier down: Alt.
</ResponseField>

<ResponseField name="KeySuper" type="bool">
  Keyboard modifier down: Windows/Super (non-macOS), Ctrl (macOS).
</ResponseField>

<ResponseField name="KeyMods" type="ImGuiKeyChord">
  Combined key modifiers flags (updated by NewFrame()).
</ResponseField>

<ResponseField name="KeysData" type="ImGuiKeyData[ImGuiKey_NamedKey_COUNT]">
  Key state for all known keys. Use `IsKeyXXX()` functions to access.
</ResponseField>

## Backend Information

<ResponseField name="BackendPlatformName" type="const char*">
  Platform backend name (informational only).
</ResponseField>

<ResponseField name="BackendRendererName" type="const char*">
  Renderer backend name (informational only).
</ResponseField>

<ResponseField name="BackendPlatformUserData" type="void*">
  User data for platform backend.
</ResponseField>

<ResponseField name="BackendRendererUserData" type="void*">
  User data for renderer backend.
</ResponseField>

## User Data

<ResponseField name="UserData" type="void*" default="NULL">
  Store your own data.
</ResponseField>

**Example:**

```cpp theme={null}
struct MyAppData {
    int some_value;
    float another_value;
};

MyAppData my_data;
ImGuiIO& io = ImGui::GetIO();
io.UserData = &my_data;

// Later:
MyAppData* data = (MyAppData*)io.UserData;
```

## Metrics

<ResponseField name="MetricsRenderVertices" type="int">
  Vertices output during last call to Render().
</ResponseField>

<ResponseField name="MetricsRenderIndices" type="int">
  Indices output during last call to Render().
</ResponseField>

<ResponseField name="MetricsRenderWindows" type="int">
  Number of visible windows.
</ResponseField>

<ResponseField name="MetricsActiveWindows" type="int">
  Number of active windows.
</ResponseField>

<ResponseField name="MouseDelta" type="ImVec2">
  Mouse delta. Zero if either current or previous position are invalid.
</ResponseField>

## Debug Options

<ResponseField name="ConfigErrorRecovery" type="bool" default="true">
  Enable error recovery support.
</ResponseField>

<ResponseField name="ConfigErrorRecoveryEnableAssert" type="bool" default="true">
  Enable asserts on recoverable errors.
</ResponseField>

<ResponseField name="ConfigErrorRecoveryEnableDebugLog" type="bool" default="true">
  Enable debug log output on recoverable errors.
</ResponseField>

<ResponseField name="ConfigErrorRecoveryEnableTooltip" type="bool" default="true">
  Enable tooltip on recoverable errors.
</ResponseField>

<ResponseField name="ConfigDebugIsDebuggerPresent" type="bool" default="false">
  Enable various tools calling IM\_DEBUG\_BREAK().
</ResponseField>

<ResponseField name="ConfigDebugHighlightIdConflicts" type="bool" default="true">
  Highlight and show error when multiple items have conflicting identifiers.
</ResponseField>

<ResponseField name="ConfigDebugBeginReturnValueOnce" type="bool" default="false">
  First-time calls to Begin()/BeginChild() will return false.
</ResponseField>

<ResponseField name="ConfigDebugBeginReturnValueLoop" type="bool" default="false">
  Some calls to Begin()/BeginChild() will return false, cycling through window depths.
</ResponseField>

## See Also

* [Input](/api/input) - Input event functions
* [Keyboard](/api/keyboard) - Keyboard input
* [Mouse](/api/mouse) - Mouse input
* [ImGuiPlatformIO](/api/imgui-io#imguiplatformio) - Platform-specific functions