Previously, any frames in flight (`requestAnimationFrame`) on web were
not being cancelled (`cancelAnimationFrame`) when `WebRunner::destroy`
was called. If a user called `destroy`, then immediately removed the
canvas from the DOM, eframe could panic with a "failed to find (canvas)
element by id" error message.
This PR changes two things:
- The canvas element is directly referenced everywhere it's needed
instead of being looked up by `canvas_id`[^1]
- The RAF handle is stored in `WebRunner` and `cancelAnimationFrame` is
called on it inside of `WebRunner::destroy`[^2]
[^1]: The WebGL/WGPU backends were already holding onto the canvas (and
associated GPU context), so the change is just converting all the
`get_element_by_id` lookups to retrieve the canvas from the web runner
handle.
[^2]: There is only ever one frame in flight, so we store it directly as
a scalar field.
* Closes#1044
---
(new PR description written by @emilk)
## Overview
This PR introduces the concept of `Viewports`, which on the native
eframe backend corresponds to native OS windows.
You can spawn a new viewport using `Context::show_viewport` and
`Cotext::show_viewport_immediate`.
These needs to be called every frame the viewport should be visible.
This is implemented by the native `eframe` backend, but not the web one.
## Viewport classes
The viewports form a tree of parent-child relationships.
There are different classes of viewports.
### Root vieport
The root viewport is the original viewport, and cannot be closed without
closing the application.
### Deferred viewports
These are created with `Context::show_viewport`.
Deferred viewports take a closure that is called by the integration at a
later time, perhaps multiple times.
Deferred viewports are repainted independenantly of the parent viewport.
This means communication with them need to done via channels, or
`Arc/Mutex`.
This is the most performant type of child viewport, though a bit more
cumbersome to work with compared to immediate viewports.
### Immediate viewports
These are created with `Context::show_viewport_immediate`.
Immediate viewports take a `FnOnce` closure, similar to other egui
functions, and is called immediately. This makes communication with them
much simpler than with deferred viewports, but this simplicity comes at
a cost: whenever tha parent viewports needs to be repainted, so will the
child viewport, and vice versa. This means that if you have `N`
viewports you are poentially doing `N` times as much CPU work. However,
if all your viewports are showing animations, and thus are repainting
constantly anyway, this doesn't matter.
In short: immediate viewports are simpler to use, but can waste a lot of
CPU time.
### Embedded viewports
These are not real, independenant viewports, but is a fallback mode for
when the integration does not support real viewports. In your callback
is called with `ViewportClass::Embedded` it means you need to create an
`egui::Window` to wrap your ui in, which will then be embedded in the
parent viewport, unable to escape it.
## Using the viewports
Only one viewport is active at any one time, identified wth
`Context::viewport_id`.
You can send commands to other viewports using
`Context::send_viewport_command_to`.
There is an example in
<https://github.com/emilk/egui/tree/master/examples/multiple_viewports/src/main.rs>.
## For integrations
There are several changes relevant to integrations.
* There is a [`crate::RawInput::viewport`] with information about the
current viewport.
* The repaint callback set by `Context::set_request_repaint_callback`
now points to which viewport should be repainted.
* `Context::run` now returns a list of viewports in `FullOutput` which
should result in their own independant windows
* There is a new `Context::set_immediate_viewport_renderer` for setting
up the immediate viewport integration
* If you support viewports, you need to call
`Context::set_embed_viewports(false)`, or all new viewports will be
embedded (the default behavior).
## Future work
* Make it easy to wrap child viewports in the same chrome as
`egui::Window`
* Automatically show embedded viewports using `egui::Window`
* Use the new `ViewportBuilder` in `eframe::NativeOptions`
* Automatically position new viewport windows (they currently cover each
other)
* Add a `Context` method for listing all existing viewports
Find more at https://github.com/emilk/egui/issues/3556
---
<details>
<summary>
Outdated PR description by @konkitoman
</summary>
## Inspiration
- Godot because the app always work desktop or single_window because of
embedding
- Dear ImGui viewport system
## What is a Viewport
A Viewport is a egui isolated component!
Can be used by the egui integration to create native windows!
When you create a Viewport is possible that the backend do not supports
that!
So you need to check if the Viewport was created or you are in the
normal egui context!
This is how you can do that:
```rust
if ctx.viewport_id() != ctx.parent_viewport_id() {
// In here you add the code for the viewport context, like
egui::CentralPanel::default().show(ctx, |ui|{
ui.label("This is in a native window!");
});
}else{
// In here you add the code for when viewport cannot be created!
// You cannot use CentralPanel in here because you will override the app CentralPanel
egui::Window::new("Virtual Viewport").show(ctx, |ui|{
ui.label("This is without a native window!\nThis is in a embedded viewport");
});
}
```
This PR do not support for drag and drop between Viewports!
After this PR is accepted i will begin work to intregrate the Viewport
system in `egui::Window`!
The `egui::Window` i want to behave the same on desktop and web
The `egui::Window` will be like Godot Window
## Changes and new
These are only public structs and functions!
<details>
<summary>
## New
</summary>
- `egui::ViewportId`
- `egui::ViewportBuilder`
This is like winit WindowBuilder
- `egui::ViewportCommand`
With this you can set any winit property on a viewport, when is a native
window!
- `egui::Context::new`
- `egui::Context::create_viewport`
- `egui::Context::create_viewport_sync`
- `egui::Context::viewport_id`
- `egui::Context::parent_viewport_id`
- `egui::Context::viewport_id_pair`
- `egui::Context::set_render_sync_callback`
- `egui::Context::is_desktop`
- `egui::Context::force_embedding`
- `egui::Context::set_force_embedding`
- `egui::Context::viewport_command`
- `egui::Context::send_viewport_command_to`
- `egui::Context::input_for`
- `egui::Context::input_mut_for`
- `egui::Context::frame_nr_for`
- `egui::Context::request_repaint_for`
- `egui::Context::request_repaint_after_for`
- `egui::Context::requested_repaint_last_frame`
- `egui::Context::requested_repaint_last_frame_for`
- `egui::Context::requested_repaint`
- `egui::Context::requested_repaint_for`
- `egui::Context::inner_rect`
- `egui::Context::outer_rect`
- `egui::InputState::inner_rect`
- `egui::InputState::outer_rect`
- `egui::WindowEvent`
</details>
<details>
<summary>
## Changes
</summary>
- `egui::Context::run`
Now needs the viewport that we want to render!
- `egui::Context::begin_frame`
Now needs the viewport that we want to render!
- `egui::Context::tessellate`
Now needs the viewport that we want to render!
- `egui::FullOutput`
```diff
- repaint_after
+ viewports
+ viewport_commands
```
- `egui::RawInput`
```diff
+ inner_rect
+ outer_rect
```
- `egui::Event`
```diff
+ WindowEvent
```
</details>
### Async Viewport
Async means that is independent from other viewports!
Is created by `egui::Context::create_viewport`
To be used you will need to wrap your state in `Arc<RwLock<T>>`
Look at viewports example to understand how to use it!
### Sync Viewport
Sync means that is dependent on his parent!
Is created by `egui::Context::create_viewport_sync`
This will pause the parent then render itself the resumes his parent!
#### ⚠️ This currently will make the fps/2 for every sync
viewport
### Common
#### ⚠️ Attention
You will need to do this when you render your content
```rust
ctx.create_viewport(ViewportBuilder::new("Simple Viewport"), | ctx | {
let content = |ui: &mut egui::Ui|{
ui.label("Content");
};
// This will make the content a popup if cannot create a native window
if ctx.viewport_id() != ctx.parent_viewport_id() {
egui::CentralPanel::default().show(ctx, content);
} else {
egui::Area::new("Simple Viewport").show(ctx, |ui| {
egui::Frame::popup(ui.style()).show(ui, content);
});
};
});
````
## What you need to know as egui user
### If you are using eframe
You don't need to change anything!
### If you have a manual implementation
Now `egui::run` or `egui::begin` and `egui::tessellate` will need the
current viewport id!
You cannot create a `ViewportId` only `ViewportId::MAIN`
If you make a single window app you will set the viewport id to be
`egui::ViewportId::MAIN` or see the `examples/pure_glow`
If you want to have multiples window support look at `crates/eframe`
glow or wgpu implementations!
## If you want to try this
- cargo run -p viewports
## This before was wanted to change
This will probably be in feature PR's
### egui::Window
To create a native window when embedded was set to false
You can try that in viewports example before:
[78a0ae8](78a0ae879e)
### egui popups, context_menu, tooltip
To be a native window
</details>
---------
Co-authored-by: Konkitoman <konkitoman@users.noreply.github.com>
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Co-authored-by: Pablo Sichert <mail@pablosichert.com>
Tested on M1 Mac:
* native
* webgl, firefox
* webgpu, chrome
all looking normal
Updated minor ahash version because 0.8.1 got yanked. Added some deny
exceptions for now - we'll have to update winit soon to resolve glow
related cargo deny errors (not a big issue though since we don't expect
wgpu and glow backends to be used at the same time)
* Make wgpu webgl/gles opt-in (but still work out of the box via feature flag), workaround canvas creation issue
* missing allow unsafe code annotations
* add breaking change not to eframe release notes
* Add --webgpu flag to build_demo_web.sh
* Improve CHANGELOG docs
* Clean up, and prepare for having to wasm:s
* put canvas without workaround under `if false`
* fix spelling
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* Replace tracing crate with log
It's just so much simpler to use
* Add `bacon wasm` job
* eframe: add a WebLogger for piping log events to the web console
* Clear color values are not explicitely sent to the rendering backend as-is.
Previously, converting from Color32 to Rgba caused an srgb->linear conversion. This conversion is incorrect if the backbuffer doesn't perform automatic conversion from linear->srgb (lack of this conversion is generally what egui assumes!).
* fill in pr numbers in changelog
* Epi comment fix
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* Color32 comment fix
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* move changelog line
* rename fix
* use backticks in doc
---------
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
* Add depth stencil initialization to `Painter`
* Move depth stencil initialization into `resize_and_generate_depth_texture_view`, and call it in `set_window` and `on_window_resized`
* Allow for depth texture in WASM builds
* change `map` to `if let` statement
* use reference for render state
* Clean up descriptors and move texture generation to on resize events
* remove unused field from WebOptions
* introduce new wgpu configuration option to allow configuring wgpu renderer
* use new options with wgpu web painter
* use on_surface_error callback
* changelog update
* cleanup
* changelog and comment fixes
* wgpu renderer now always requires a RenderPass being passed in
This also implies that it no longer owns the depth buffer! (why would it anyways!)
* wgpu-renderer now passes a command encoder to prepare
* add changelog entries
* fixup changelogs, fix variable name
* basic working wgpu @ webgl on websys
* fix glow compile error
* introduced WebPainter trait, provide wgpu renderstate
* WebPainterWgpu destroy implemented
* make custom3d demo work on wgpu backend
* changelog entry for wgpu support eframe wasm
* remove temporary logging hack
* stop using pollster for web
we're actually not allowed to block - this only worked because wgpu on webgl doesn't actually cause anything blocking. However, when trying webgpu this became an issue
* revert cargo update
* compile error if neither glow nor wgpu features are enabled
* code cleanup
* Error handling
* Update changelog with link
* Make sure --all-features work
* Select best framebuffer format from the available ones
* update to wasm-bindgen 0.2.83
* Fix typo
* Clean up Cargo.toml
* Log about using the wgpu painter
* fixup wgpu labels
* fix custom3d_wgpu_shader ub padding
* remove duplicated uniforms struct in wgsl shader for custom3d
* Update docs: add async/await to the web 'start' function
Co-authored-by: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Jan Procházka
Jonas Wagner
Emil Ernerfeldt
Andreas Reich
Konkitoman
Niklas Korz
Red Artist
Lukas Hermann
Clement Rey
Andreas Reich