kui_core/metrics.rs
1//! [`Metrics`]: the sizes the stock widgets are built from, one struct
2//! beside the palette.
3//!
4//! Every field is logical px (or a text size in logical px), applied
5//! before `env.scale`, which the renderer multiplies everything by.
6//! Density is the app's choice, as the palette is: [`Metrics::compact`]
7//! is a tighter set, [`Metrics::scaled`] multiplies every length for a
8//! density slider, and `Core::set_metrics` makes one the frame's. An app
9//! that never sets one gets [`Metrics::default`], the stock geometry.
10//!
11//! Fields are roles, like the palette's: `control_pad_x` is a button's
12//! horizontal padding, not "spacing unit 3", and a view that wants a
13//! number between two has arithmetic.
14
15/// The titlebar's height on Windows and everywhere else: the caption
16/// height the OS draws, so the one metric that is the platform's rather
17/// than a density's. Named here so [`Metrics::comfortable`] picks the
18/// running one and the schema row (`MetricRole::platform`) carries both,
19/// which is what keeps a generated table from saying which machine wrote
20/// it.
21pub const TITLEBAR_H_WINDOWS: f32 = 32.0;
22pub const TITLEBAR_H_ELSEWHERE: f32 = 34.0;
23
24/// The sizes the stock widgets are built from. Plain data and [`Copy`]: a
25/// view reads it off `ui.metrics()` and may keep or change its own copy,
26/// and `Core::set_metrics` makes one the frame's.
27#[derive(Clone, Copy, Debug, PartialEq)]
28pub struct Metrics {
29 // -- text ----------------------------------------------------------
30 /// A stock control's label: the button's text size.
31 pub control_text: f32,
32 /// The chrome's text: a menu row, a menu-bar title, the titlebar's
33 /// title.
34 pub chrome_text: f32,
35 /// A tooltip's text.
36 pub hint_text: f32,
37
38 // -- corners -------------------------------------------------------
39 /// The corner of every stock surface: a button, a field, a menu, a
40 /// tooltip.
41 pub radius: f32,
42 /// The corner of a row inside one: a menu row, a menu-bar title.
43 pub radius_inner: f32,
44
45 // -- padding, x then y -----------------------------------------------
46 /// A button's.
47 pub control_pad_x: f32,
48 pub control_pad_y: f32,
49 /// A text field's.
50 pub field_pad_x: f32,
51 pub field_pad_y: f32,
52 /// A tooltip's.
53 pub hint_pad_x: f32,
54 pub hint_pad_y: f32,
55 /// A menu row's; a menu-bar title's is two px shorter, so the bar's
56 /// height and not the title's padding decides the strip.
57 pub menu_pad_x: f32,
58 pub menu_pad_y: f32,
59
60 // -- extents -------------------------------------------------------
61 /// A menu panel's width.
62 pub menu_width: f32,
63 /// The drawn menu bar's height.
64 pub menu_bar_h: f32,
65 /// The titlebar strip's height: the platform's caption height (32 on
66 /// Windows, 34 elsewhere), which [`Metrics::compact`] leaves alone. A
67 /// driver that knows the window's strip is another height makes it
68 /// that window's platform height, and the stock number stands for it
69 /// in [`Core::set_metrics`](crate::runtime::Core::set_metrics)
70 /// (backlog W22): the runner's `Launcher::titlebar` off macOS (40 or
71 /// 52), and under macOS custom chrome the OS's own titlebar, as tall
72 /// as the runner measures it into `env.window.native_controls` (32,
73 /// 40 or 52 on macOS 27). There the strip is drawn at the measured
74 /// height whatever this row says (`widgets::titlebar_height`).
75 pub titlebar_h: f32,
76}
77
78impl Default for Metrics {
79 /// What the widgets have always drawn: the constants `widgets.rs`
80 /// carried, restated once.
81 fn default() -> Self {
82 Self::comfortable()
83 }
84}
85
86impl Metrics {
87 /// The stock set — [`Default`], named.
88 pub const fn comfortable() -> Self {
89 Metrics {
90 control_text: 15.0,
91 chrome_text: 13.0,
92 hint_text: 12.0,
93 radius: 6.0,
94 radius_inner: 4.0,
95 control_pad_x: 14.0,
96 control_pad_y: 8.0,
97 field_pad_x: 10.0,
98 field_pad_y: 8.0,
99 hint_pad_x: 10.0,
100 hint_pad_y: 6.0,
101 menu_pad_x: 8.0,
102 menu_pad_y: 5.0,
103 menu_width: 200.0,
104 menu_bar_h: 26.0,
105 titlebar_h: if cfg!(target_os = "windows") {
106 TITLEBAR_H_WINDOWS
107 } else {
108 TITLEBAR_H_ELSEWHERE
109 },
110 }
111 }
112
113 /// A tighter set for a dense tool — a mux, an inspector, a table of
114 /// controls: smaller text, shallower padding, sharper corners. The
115 /// titlebar keeps the platform's height, since that is the OS's
116 /// number and not a density.
117 pub const fn compact() -> Self {
118 Metrics {
119 control_text: 13.0,
120 chrome_text: 12.0,
121 hint_text: 11.0,
122 radius: 4.0,
123 radius_inner: 3.0,
124 control_pad_x: 10.0,
125 control_pad_y: 5.0,
126 field_pad_x: 8.0,
127 field_pad_y: 5.0,
128 hint_pad_x: 8.0,
129 hint_pad_y: 4.0,
130 menu_pad_x: 8.0,
131 menu_pad_y: 3.0,
132 menu_width: 180.0,
133 menu_bar_h: 22.0,
134 ..Self::comfortable()
135 }
136 }
137
138 /// Every density multiplied by `factor` — a density slider, or an OS
139 /// text-size setting the day one is plumbed. Logical px in, logical
140 /// px out: `env.scale` is applied after this by the renderer and is
141 /// never folded in here. A row the schema marks the platform's
142 /// (`titlebar_h`: the OS's caption height, which the traffic lights
143 /// are drawn against) is left alone, as [`Metrics::compact`] leaves
144 /// it — a 1.5 slider drew a 51 px strip beside 34 px buttons.
145 pub fn scaled(self, factor: f32) -> Self {
146 let mut m = self;
147 for row in crate::schema::METRIC_ROLES {
148 if row.platform.is_some() {
149 continue;
150 }
151 (row.set)(&mut m, (row.get)(&self) * factor);
152 }
153 m
154 }
155}