1//! # Welcome to GPUI!
2//!
3//! GPUI is a hybrid immediate and retained mode, GPU accelerated, UI framework
4//! for Rust, designed to support a wide variety of applications.
5//!
6//! ## Getting Started
7//!
8//! GPUI is still in active development as we work on the Zed code editor and isn't yet on crates.io.
9//! You'll also need to use the latest version of stable rust. Add the following to your Cargo.toml:
10//!
11//! ```
12//! gpui = { git = "https://github.com/zed-industries/zed" }
13//! ```
14//!
15//! Everything in GPUI starts with an [`App`]. You can create one with [`App::new`], and
16//! kick off your application by passing a callback to [`App::run`]. Inside this callback,
17//! you can create a new window with [`AppContext::open_window`], and register your first root
18//! view. See [gpui.rs](https://www.gpui.rs/) for a complete example.
19//!
20//! ## The Big Picture
21//!
22//! GPUI offers three different [registers](https://en.wikipedia.org/wiki/Register_(sociolinguistics)) depending on your needs:
23//!
24//! - State management and communication with Models. Whenever you need to store application state
25//! that communicates between different parts of your application, you'll want to use GPUI's
26//! models. Models are owned by GPUI and are only accessible through an owned smart pointer
27//! similar to an [`Rc`]. See the [`app::model_context`] module for more information.
28//!
29//! - High level, declarative UI with Views. All UI in GPUI starts with a View. A view is simply
30//! a model that can be rendered, via the [`Render`] trait. At the start of each frame, GPUI
31//! will call this render method on the root view of a given window. Views build a tree of
32//! `elements`, lay them out and style them with a tailwind-style API, and then give them to
33//! GPUI to turn into pixels. See the [`elements::Div`] element for an all purpose swiss-army
34//! knife for UI.
35//!
36//! - Low level, imperative UI with Elements. Elements are the building blocks of UI in GPUI, and they
37//! provide a nice wrapper around an imperative API that provides as much flexibility and control as
38//! you need. Elements have total control over how they and their child elements are rendered and
39//! can be used for making efficient views into large lists, implement custom layouting for a code editor,
40//! and anything else you can think of. See the [`element`] module for more information.
41//!
42//! Each of these registers has one or more corresponding contexts that can be accessed from all GPUI services.
43//! This context is your main interface to GPUI, and is used extensively throughout the framework.
44//!
45//! ## Other Resources
46//!
47//! In addition to the systems above, GPUI provides a range of smaller services that are useful for building
48//! complex applications:
49//!
50//! - Actions are user-defined structs that are used for converting keystrokes into logical operations in your UI.
51//! Use this for implementing keyboard shortcuts, such as cmd-q. See the [`action`] module for more information.
52//! - Platform services, such as `quit the app` or `open a URL` are available as methods on the [`app::AppContext`].
53//! - An async executor that is integrated with the platform's event loop. See the [`executor`] module for more information.,
54//! - The [gpui::test] macro provides a convenient way to write tests for your GPUI applications. Tests also have their
55//! own kind of context, a [`TestAppContext`] which provides ways of simulating common platform input. See [`app::test_context`]
56//! and [`test`] modules for more details.
57//!
58//! Currently, the best way to learn about these APIs is to read the Zed source code, ask us about it at a fireside hack, or drop
59//! a question in the [Zed Discord](https://zed.dev/community-links). We're working on improving the documentation, creating more examples,
60//! and will be publishing more guides to GPUI on our [blog](https://zed.dev/blog).
61
62#![deny(missing_docs)]
63#![allow(clippy::type_complexity)] // Not useful, GPUI makes heavy use of callbacks
64#![allow(clippy::collapsible_else_if)] // False positives in platform specific code
65#![allow(unused_mut)] // False positives in platform specific code
66
67#[macro_use]
68mod action;
69mod app;
70
71mod arena;
72mod asset_cache;
73mod assets;
74mod bounds_tree;
75mod color;
76mod element;
77mod elements;
78mod executor;
79mod geometry;
80mod global;
81mod input;
82mod interactive;
83mod key_dispatch;
84mod keymap;
85mod platform;
86pub mod prelude;
87mod scene;
88mod shared_string;
89mod shared_uri;
90mod style;
91mod styled;
92mod subscription;
93mod svg_renderer;
94mod taffy;
95#[cfg(any(test, feature = "test-support"))]
96pub mod test;
97mod text_system;
98mod util;
99mod view;
100mod window;
101
102/// Do not touch, here be dragons for use by gpui_macros and such.
103#[doc(hidden)]
104pub mod private {
105 pub use linkme;
106 pub use serde;
107 pub use serde_derive;
108 pub use serde_json;
109}
110
111mod seal {
112 /// A mechanism for restricting implementations of a trait to only those in GPUI.
113 /// See: https://predr.ag/blog/definitive-guide-to-sealed-traits-in-rust/
114 pub trait Sealed {}
115}
116
117pub use action::*;
118pub use anyhow::Result;
119pub use app::*;
120pub(crate) use arena::*;
121pub use asset_cache::*;
122pub use assets::*;
123pub use color::*;
124pub use ctor::ctor;
125pub use element::*;
126pub use elements::*;
127pub use executor::*;
128pub use geometry::*;
129pub use global::*;
130pub use gpui_macros::{register_action, test, IntoElement, Render};
131pub use http_client;
132pub use input::*;
133pub use interactive::*;
134use key_dispatch::*;
135pub use keymap::*;
136pub use platform::*;
137pub use refineable::*;
138pub use scene::*;
139use seal::Sealed;
140pub use shared_string::*;
141pub use shared_uri::*;
142pub use smol::Timer;
143pub use style::*;
144pub use styled::*;
145pub use subscription::*;
146use svg_renderer::*;
147pub use taffy::{AvailableSpace, LayoutId};
148#[cfg(any(test, feature = "test-support"))]
149pub use test::*;
150pub use text_system::*;
151pub use util::arc_cow::ArcCow;
152pub use view::*;
153pub use window::*;
154
155use std::{any::Any, borrow::BorrowMut};
156use taffy::TaffyLayoutEngine;
157
158/// The context trait, allows the different contexts in GPUI to be used
159/// interchangeably for certain operations.
160pub trait Context {
161 /// The result type for this context, used for async contexts that
162 /// can't hold a direct reference to the application context.
163 type Result<T>;
164
165 /// Create a new model in the app context.
166 fn new_model<T: 'static>(
167 &mut self,
168 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
169 ) -> Self::Result<Model<T>>;
170
171 /// Reserve a slot for a model to be inserted later.
172 /// The returned [Reservation] allows you to obtain the [EntityId] for the future model.
173 fn reserve_model<T: 'static>(&mut self) -> Self::Result<Reservation<T>>;
174
175 /// Insert a new model in the app context based on a [Reservation] previously obtained from [`reserve_model`].
176 ///
177 /// [`reserve_model`]: Self::reserve_model
178 fn insert_model<T: 'static>(
179 &mut self,
180 reservation: Reservation<T>,
181 build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
182 ) -> Self::Result<Model<T>>;
183
184 /// Update a model in the app context.
185 fn update_model<T, R>(
186 &mut self,
187 handle: &Model<T>,
188 update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
189 ) -> Self::Result<R>
190 where
191 T: 'static;
192
193 /// Read a model from the app context.
194 fn read_model<T, R>(
195 &self,
196 handle: &Model<T>,
197 read: impl FnOnce(&T, &AppContext) -> R,
198 ) -> Self::Result<R>
199 where
200 T: 'static;
201
202 /// Update a window for the given handle.
203 fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
204 where
205 F: FnOnce(AnyView, &mut WindowContext) -> T;
206
207 /// Read a window off of the application context.
208 fn read_window<T, R>(
209 &self,
210 window: &WindowHandle<T>,
211 read: impl FnOnce(View<T>, &AppContext) -> R,
212 ) -> Result<R>
213 where
214 T: 'static;
215}
216
217/// Returned by [Context::reserve_model] to later be passed to [Context::insert_model].
218/// Allows you to obtain the [EntityId] for a model before it is created.
219pub struct Reservation<T>(pub(crate) Slot<T>);
220
221impl<T: 'static> Reservation<T> {
222 /// Returns the [EntityId] that will be associated with the model once it is inserted.
223 pub fn entity_id(&self) -> EntityId {
224 self.0.entity_id()
225 }
226}
227
228/// This trait is used for the different visual contexts in GPUI that
229/// require a window to be present.
230pub trait VisualContext: Context {
231 /// Construct a new view in the window referenced by this context.
232 fn new_view<V>(
233 &mut self,
234 build_view: impl FnOnce(&mut ViewContext<V>) -> V,
235 ) -> Self::Result<View<V>>
236 where
237 V: 'static + Render;
238
239 /// Update a view with the given callback
240 fn update_view<V: 'static, R>(
241 &mut self,
242 view: &View<V>,
243 update: impl FnOnce(&mut V, &mut ViewContext<V>) -> R,
244 ) -> Self::Result<R>;
245
246 /// Replace the root view of a window with a new view.
247 fn replace_root_view<V>(
248 &mut self,
249 build_view: impl FnOnce(&mut ViewContext<V>) -> V,
250 ) -> Self::Result<View<V>>
251 where
252 V: 'static + Render;
253
254 /// Focus a view in the window, if it implements the [`FocusableView`] trait.
255 fn focus_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
256 where
257 V: FocusableView;
258
259 /// Dismiss a view in the window, if it implements the [`ManagedView`] trait.
260 fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
261 where
262 V: ManagedView;
263}
264
265/// A trait that allows models and views to be interchangeable in certain operations
266pub trait Entity<T>: Sealed {
267 /// The weak reference type for this entity.
268 type Weak: 'static;
269
270 /// The ID for this entity
271 fn entity_id(&self) -> EntityId;
272
273 /// Downgrade this entity to a weak reference.
274 fn downgrade(&self) -> Self::Weak;
275
276 /// Upgrade this entity from a weak reference.
277 fn upgrade_from(weak: &Self::Weak) -> Option<Self>
278 where
279 Self: Sized;
280}
281
282/// A trait for tying together the types of a GPUI entity and the events it can
283/// emit.
284pub trait EventEmitter<E: Any>: 'static {}
285
286/// A helper trait for auto-implementing certain methods on contexts that
287/// can be used interchangeably.
288pub trait BorrowAppContext {
289 /// Set a global value on the context.
290 fn set_global<T: Global>(&mut self, global: T);
291 /// Updates the global state of the given type.
292 fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
293 where
294 G: Global;
295 /// Updates the global state of the given type, creating a default if it didn't exist before.
296 fn update_default_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
297 where
298 G: Global + Default;
299}
300
301impl<C> BorrowAppContext for C
302where
303 C: BorrowMut<AppContext>,
304{
305 fn set_global<G: Global>(&mut self, global: G) {
306 self.borrow_mut().set_global(global)
307 }
308
309 #[track_caller]
310 fn update_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
311 where
312 G: Global,
313 {
314 let mut global = self.borrow_mut().lease_global::<G>();
315 let result = f(&mut global, self);
316 self.borrow_mut().end_global_lease(global);
317 result
318 }
319
320 fn update_default_global<G, R>(&mut self, f: impl FnOnce(&mut G, &mut Self) -> R) -> R
321 where
322 G: Global + Default,
323 {
324 self.borrow_mut().default_global::<G>();
325 self.update_global(f)
326 }
327}
328
329/// A flatten equivalent for anyhow `Result`s.
330pub trait Flatten<T> {
331 /// Convert this type into a simple `Result<T>`.
332 fn flatten(self) -> Result<T>;
333}
334
335impl<T> Flatten<T> for Result<Result<T>> {
336 fn flatten(self) -> Result<T> {
337 self?
338 }
339}
340
341impl<T> Flatten<T> for Result<T> {
342 fn flatten(self) -> Result<T> {
343 self
344 }
345}
346
347/// Information about the GPU GPUI is running on.
348#[derive(Default, Debug)]
349pub struct GpuSpecs {
350 /// Whether the GPU is really a fake (like `llvmpipe`) running on the CPU.
351 pub is_software_emulated: bool,
352 /// The name of the device, as reported by Vulkan.
353 pub device_name: String,
354 /// The name of the driver, as reported by Vulkan.
355 pub driver_name: String,
356 /// Further information about the driver, as reported by Vulkan.
357 pub driver_info: String,
358}