Touch and pen

Standard widgets use the framework pointer and gesture system for mouse, touch, and stylus input. Custom widgets should use the same event context rather than track a global mouse position.

Minimal example

This helper can be called from a pointer handler:

#![allow(unused)]
fn main() {
use teksilo::prelude::*;

fn inspect_pointer(ctx: &EventContext) {
    let kind = ctx.pointer_kind();
    let position = ctx.pointer_position();
    println!("{kind:?} at {position:?}");
}
}

pointer_position() is optional and uses window-logical coordinates; ctx.to_local(p) converts a window-logical point into the handler's own space. pointer() provides the current pointer identity and axes. Outside pointer, scroll, gesture, or drag dispatch, the context uses fallback pointer information; do not interpret that fallback as a new physical sample.

Common operations

• Use activation handlers for buttons. A direct-pointer press can become a pan or be cancelled before activation.
• Use pointer_kind() to distinguish coarse input from mouse input.
• Use owns_pointer() when handling moves during a captured interaction.
• Handle PointerCancel as terminal: clear drag, pressed, and preview state.
• Use coalesced() before the current sample when every stylus position matters. These samples also use window-logical coordinates; convert each with ctx.to_local.
• Use scroll_source() and scroll_phase() to distinguish wheel input, touch panning, and trackpad momentum.
• Provide a press or keyboard route for controls otherwise exposed only on hover.

Related guides

Constraints

Touch and pen capabilities vary by backend, device, and compositor. A finger does not generate hover. Stylus pressure, tilt, proximity, and batched samples must be treated as capabilities, not universal inputs.

The current Wayland integration cannot initiate native window movement with a touch serial. Test custom window chrome on the target compositor. Hardware verification is still required for touch, stylus, trackpad, and screen reader combinations; headless tests do not establish device support.

Reference

• Pointer types
• Event context
• Platform source

Engineering reference

Implementation details and review history are retained in the repository.