Selecting Capture Targets

wgc provides multiple ways to select a target (GraphicsCaptureItem) for screen or window capture.

1. Using the Interactive Picker

The interactive picker displays a native Windows UI dialog that lets the user select any open window or monitor screen.

use wgc::new_item_with_picker;

fn main() -> anyhow::Result<()> {
    // Pass None for parent window handle, or Some(parent_hwnd) to center the picker over a specific window
    let item = new_item_with_picker(None)?;
    println!("Selected target: {}", item.DisplayName()?);
    Ok(())
}

2. Target by Window Handle (HWND)

If you know the window handle (HWND) of a specific application window, you can target it directly without showing a UI picker:

use wgc::new_item_for_window;
use windows::Win32::Foundation::HWND;

fn capture_window(hwnd: HWND) -> anyhow::Result<()> {
    let item = new_item_for_window(hwnd)?;
    println!("Capturing window: {}", item.DisplayName()?);
    Ok(())
}

3. Target by Monitor Handle (HMONITOR)

Similarly, you can capture an entire monitor display directly by passing its HMONITOR handle:

use wgc::new_item_for_monitor;
use windows::Win32::Graphics::Gdi::HMONITOR;

fn capture_monitor(hmonitor: HMONITOR) -> anyhow::Result<()> {
    let item = new_item_for_monitor(hmonitor)?;
    println!("Capturing monitor: {}", item.DisplayName()?);
    Ok(())
}

Target Properties

The returned GraphicsCaptureItem is a WinRT object. You can query its properties such as display name or size:

let name = item.DisplayName()?;
let size = item.Size()?;
println!("Target name: {}, size: {}x{}", name, size.Width, size.Height);