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yog_ui/
lib.rs

1//! yog-ui — retained-mode UI framework for Yog mods.
2//!
3//! Flexbox-inspired layout engine + GPU rendering via [`yog-gfx`].
4//! Use for custom inventories, guide books, tooltips, HUD overlays.
5//!
6//! # Quick start
7//! ```ignore
8//! use yog_ui::{UiRoot, widget, Align, FlexDir, Units};
9//!
10//! let ui = UiRoot::new("mymod:main_menu")
11//!     .style(|s| s.bg(0x88332211).padding(8.0, 8.0, 8.0, 8.0))
12//!     .child(
13//!         widget::panel(FlexDir::Column).gap(4.0)
14//!             .child(widget::label("Hello, World!").color(0xFF_DDAA00))
15//!             .child(widget::button("Click me").on_click("mymod:btn_click"))
16//!     );
17//! ```
18
19pub mod layout;
20mod render;
21pub mod scroll;
22pub mod text;
23pub mod textbox;
24pub mod widget;
25
26pub use layout::{set_focus, Align, FlexDir, LayoutNode, Rect};
27pub use scroll::ScrollState;
28pub use textbox::{TextBoxEvent, TextBoxState};
29pub use widget::{Dock, FocusStyle, Units, Widget};
30
31use yog_gfx::GfxContext;
32
33/// Top-level UI tree.  Build it, call [`layout`], then [`render`] each frame.
34pub struct UiRoot {
35    pub id: String,
36    pub root: Widget,
37    pub layout_root: LayoutNode,
38    pub needs_layout: bool,
39}
40
41impl UiRoot {
42    pub fn new(id: impl Into<String>, root: Widget) -> Self {
43        Self {
44            id: id.into(),
45            root,
46            layout_root: LayoutNode::default(),
47            needs_layout: true,
48        }
49    }
50
51    /// Recalculate layout. Call after changing the tree or on window resize.
52    pub fn layout(&mut self, screen_w: f32, screen_h: f32) {
53        self.layout_root = layout::compute(&self.root, screen_w, screen_h);
54        self.needs_layout = false;
55    }
56
57    /// Render the UI tree via `yog-gfx` draw2d.
58    /// Must be called from `on_hud_render`.
59    pub fn render(&self, ctx: &GfxContext) {
60        text::use_host_metrics(ctx);
61        let d2d = ctx.draw2d();
62        render::render_node(&d2d, &self.root, &self.layout_root);
63    }
64
65    /// Find the deepest clickable widget at `(mx, my)` in screen coordinates.
66    pub fn hit_test(&self, mx: f32, my: f32) -> Option<&LayoutNode> {
67        layout::hit_test(&self.layout_root, mx, my)
68    }
69
70    /// Resolved rect of the (first) node tagged `id` — see [`layout::find_by_id`].
71    /// Call after [`Self::layout`].
72    pub fn find_rect(&self, id: &str) -> Option<Rect> {
73        layout::find_by_id(&self.layout_root, id)
74    }
75
76    /// Laid-out node of the (first) widget tagged `id` — rect plus scroll
77    /// state, see [`layout::find_node`]. Call after [`Self::layout`].
78    pub fn find_node(&self, id: &str) -> Option<&LayoutNode> {
79        layout::find_node(&self.layout_root, id)
80    }
81}