retroglyph_widgets/interact/
sense.rs

1//! [`Sense`]: what a widget wants [`Interaction::interact`](crate::Interaction::interact)
2//! to compute on its behalf.
3
4use core::ops::{BitOr, BitOrAssign};
5
6/// Which of a [`Response`](crate::Response)'s fields
7/// [`Interaction::interact`](crate::Interaction::interact) should actually
8/// populate for a given widget call.
9///
10/// A manual bitflag over `u8`: mirrors
11/// [`KeyModifiers`](retroglyph_core::KeyModifiers)'s shape rather than
12/// pulling in the `bitflags` crate for five bits. Combine raw flags with
13/// `|` (`Sense::HOVER | Sense::FOCUSABLE`), or reach for one of the named
14/// constructors ([`click`](Self::click), [`drag`](Self::drag),
15/// [`hover`](Self::hover), [`scroll`](Self::scroll)) for the common cases.
16#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash, Default)]
17pub struct Sense(u8);
18
19impl Sense {
20    /// Register the widget's rect for hit-testing and report
21    /// [`Response::hovered`](crate::Response::hovered).
22    pub const HOVER: Self = Self(1 << 0);
23    /// Report [`Response::pressed`](crate::Response::pressed),
24    /// [`Response::released`](crate::Response::released), and
25    /// [`Response::clicked`](crate::Response::clicked).
26    pub const CLICK: Self = Self(1 << 1);
27    /// Report [`Response::dragging`](crate::Response::dragging) once the
28    /// pointer moves past the drag threshold while pressed on this widget.
29    pub const DRAG: Self = Self(1 << 2);
30    /// Register the widget in the [`FocusRing`](crate::FocusRing)'s
31    /// Tab/Shift+Tab order and report
32    /// [`Response::focused`](crate::Response::focused). Combined with
33    /// [`CLICK`](Self::CLICK), Enter/Space also activate the widget while
34    /// it's focused: terminals are frequently mouse-less.
35    pub const FOCUSABLE: Self = Self(1 << 3);
36    /// Report [`Response::scroll_delta`](crate::Response::scroll_delta)
37    /// whenever the pointer is within this widget's rect. Unlike the other
38    /// pointer senses, this is deliberately *not* limited to the single
39    /// topmost widget under the pointer: see [`Interaction::interact`](crate::Interaction::interact)'s
40    /// doc comment on `scroll_delta` for why.
41    pub const SCROLL: Self = Self(1 << 4);
42    /// Report [`Response::secondary_clicked`](crate::Response::secondary_clicked):
43    /// the secondary (right) button pressed and released on this widget
44    /// while still hovered. Independent of [`CLICK`](Self::CLICK): combine
45    /// them (`Sense::click() | Sense::SECONDARY_CLICK`) for a widget that
46    /// wants both a primary action and a secondary one (e.g. a context
47    /// menu). Unlike [`CLICK`](Self::CLICK)/[`DRAG`](Self::DRAG), there's no
48    /// drag-threshold suppression for the secondary button: a
49    /// press-and-release on the same widget always counts, since
50    /// secondary-button drags aren't a gesture this module resolves.
51    pub const SECONDARY_CLICK: Self = Self(1 << 5);
52    /// Senses nothing: [`interact`](crate::Interaction::interact) still
53    /// registers the id nowhere and returns [`Response::default`](crate::Response).
54    pub const NONE: Self = Self(0);
55
56    /// A clickable, hoverable, focusable widget: buttons, tabs, list
57    /// rows. Equivalent to `HOVER | CLICK | FOCUSABLE`.
58    #[must_use]
59    pub const fn click() -> Self {
60        Self(Self::HOVER.0 | Self::CLICK.0 | Self::FOCUSABLE.0)
61    }
62
63    /// A draggable widget, e.g. a slider or scrollbar thumb. Equivalent to
64    /// <code>[click](Self::click) | DRAG</code>.
65    #[must_use]
66    pub const fn drag() -> Self {
67        Self(Self::click().0 | Self::DRAG.0)
68    }
69
70    /// A hover-only widget with no click or focus behavior, e.g. a tooltip
71    /// trigger. Equivalent to `HOVER`.
72    #[must_use]
73    pub const fn hover() -> Self {
74        Self::HOVER
75    }
76
77    /// A scrollable region, e.g. a list or log panel. Equivalent to
78    /// `HOVER | SCROLL`.
79    #[must_use]
80    pub const fn scroll() -> Self {
81        Self(Self::HOVER.0 | Self::SCROLL.0)
82    }
83
84    /// A widget with a secondary (right-click) action but no primary click,
85    /// e.g. a context-menu-only trigger. Equivalent to `HOVER | SECONDARY_CLICK`.
86    /// Combine with [`click`](Self::click) (`Sense::click() | Sense::SECONDARY_CLICK`)
87    /// for a widget with both a primary and a secondary action.
88    #[must_use]
89    pub const fn secondary_click() -> Self {
90        Self(Self::HOVER.0 | Self::SECONDARY_CLICK.0)
91    }
92
93    /// `true` if every bit set in `other` is also set in `self`.
94    #[must_use]
95    pub const fn contains(self, other: Self) -> bool {
96        (self.0 & other.0) == other.0
97    }
98
99    /// `true` if this sense wants pointer hit-testing at all ([`HOVER`](Self::HOVER),
100    /// [`CLICK`](Self::CLICK), [`DRAG`](Self::DRAG), [`SCROLL`](Self::SCROLL),
101    /// or [`SECONDARY_CLICK`](Self::SECONDARY_CLICK)).
102    #[must_use]
103    pub const fn wants_pointer(self) -> bool {
104        self.0
105            & (Self::HOVER.0
106                | Self::CLICK.0
107                | Self::DRAG.0
108                | Self::SCROLL.0
109                | Self::SECONDARY_CLICK.0)
110            != 0
111    }
112}
113
114impl BitOr for Sense {
115    type Output = Self;
116
117    fn bitor(self, rhs: Self) -> Self {
118        Self(self.0 | rhs.0)
119    }
120}
121
122impl BitOrAssign for Sense {
123    fn bitor_assign(&mut self, rhs: Self) {
124        self.0 |= rhs.0;
125    }
126}
127
128#[cfg(test)]
129mod tests {
130    use super::*;
131
132    #[test]
133    fn contains_checks_all_bits() {
134        let s = Sense::HOVER | Sense::FOCUSABLE;
135        assert!(s.contains(Sense::HOVER));
136        assert!(s.contains(Sense::FOCUSABLE));
137        assert!(!s.contains(Sense::CLICK));
138        assert!(s.contains(Sense::NONE)); // vacuously true
139    }
140
141    #[test]
142    fn constructors_match_their_documented_bit_combinations() {
143        assert_eq!(
144            Sense::click(),
145            Sense::HOVER | Sense::CLICK | Sense::FOCUSABLE
146        );
147        assert_eq!(Sense::drag(), Sense::click() | Sense::DRAG);
148        assert_eq!(Sense::hover(), Sense::HOVER);
149        assert_eq!(Sense::scroll(), Sense::HOVER | Sense::SCROLL);
150    }
151
152    #[test]
153    fn wants_pointer_ignores_focusable() {
154        assert!(!Sense::FOCUSABLE.wants_pointer());
155        assert!(Sense::HOVER.wants_pointer());
156        assert!(Sense::CLICK.wants_pointer());
157        assert!(Sense::DRAG.wants_pointer());
158        assert!(Sense::SCROLL.wants_pointer());
159        assert!(!Sense::NONE.wants_pointer());
160    }
161
162    #[test]
163    fn default_is_none() {
164        assert_eq!(Sense::default(), Sense::NONE);
165    }
166}
retroglyph_widgets/interact/sense.rs

retroglyph_widgets/interact/
sense.rs
