egui/crates/eframe
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eframe: Repaint immediately on RepaintAsap, fixes #903 (#2280)
* eframe: Repaint immediately on RepaintAsap, fixes #903

This completely eliminates the white flickering seen on Windows when
rapidly resizing a window on the glow backend. The reason that happens
is because DWM only waits for the resize event to be delivered before
displaying the window at its new size. You must repaint synchronously
inside that iteration of the event loop or else you get flickering.

* Differentiate between RepaintAsap and RepaintNext

RepaintNext looks like it is indeed needed in at least one case instead
of RepaintAsap.

* Use RepaintNext in more situations

Starting to understand why this was the behavior. It looks like only a
few special cases should be given RepaintAsap, such as the window being
resized. All other cases should be RepaintNext, as it can wait.

Using RepaintAsap in all situations will cause things like lag when
changing a slider by keyboard with a high key repeat rate.

* Add explanatory comments

I am a total hypocrite for forgetting to add these.

* Rename RepaintAsap to RepaintNow

There is no notion of "possibility" here like there is when waiting for
RedrawEventsCleared. RepaintNow causes an immediate repaint no matter
what.

* Fix RepaintNow comment

"Delays" is ambiguous.
2022-11-13 20:30:39 +01:00
..
src eframe: Repaint immediately on RepaintAsap, fixes #903 (#2280) 2022-11-13 20:30:39 +01:00
Cargo.toml bump msrv 1.64 and tts + bindgen dep (#2274) 2022-11-11 10:27:25 +01:00
CHANGELOG.md eframe: make sure to update native_pixels_per_point when dpi changes (#2256) 2022-11-07 12:36:17 +01:00
README.md Fix broken GitHub source links due to #1940 2022-08-20 15:18:02 +02:00

eframe: the egui framework

Latest version Documentation unsafe forbidden MIT Apache

eframe is the official framework library for writing apps using egui. The app can be compiled both to run natively (cross platform) or be compiled to a web app (using WASM).

To get started, see the examples. To learn how to set up eframe for web and native, go to https://github.com/emilk/eframe_template/ and follow the instructions there!

There is also a tutorial video at https://www.youtube.com/watch?v=NtUkr_z7l84.

For how to use egui, see the egui docs.


eframe uses egui_glow for rendering, and on native it uses egui-winit.

To use on Linux, first run:

sudo apt-get install libxcb-render0-dev libxcb-shape0-dev libxcb-xfixes0-dev libspeechd-dev libxkbcommon-dev libssl-dev

You need to either use edition = "2021", or set resolver = "2" in the [workspace] section of your to-level Cargo.toml. See this link for more info.

You can opt-in to the using egui_wgpu for rendering by enabling the wgpu feature and setting NativeOptions::renderer to Renderer::Wgpu.

Alternatives

eframe is not the only way to write an app using egui! You can also try egui-miniquad, bevy_egui, egui_sdl2_gl, and others.

You can also use egui_glow and winit to build your own app as demonstrated in https://github.com/emilk/egui/blob/master/crates/egui_glow/examples/pure_glow.rs.

Problems with running egui on the web

eframe uses WebGL (via glow) and WASM, and almost nothing else from the web tech stack. This has some benefits, but also produces some challenges and serious downsides.

  • Rendering: Getting pixel-perfect rendering right on the web is very difficult.
  • Search: you cannot search an egui web page like you would a normal web page.
  • Bringing up an on-screen keyboard on mobile: there is no JS function to do this, so eframe fakes it by adding some invisible DOM elements. It doesn't always work.
  • Mobile text editing is not as good as for a normal web app.
  • Accessibility: There is an experimental screen reader for eframe, but it has to be enabled explicitly. There is no JS function to ask "Does the user want a screen reader?" (and there should probably not be such a function, due to user tracking/integrity concerns).
  • No integration with browser settings for colors and fonts.
  • On Linux and Mac, Firefox will copy the WebGL render target from GPU, to CPU and then back again (https://bugzilla.mozilla.org/show_bug.cgi?id=1010527#c0), slowing down egui.

In many ways, eframe is trying to make the browser do something it wasn't designed to do (though there are many things browser vendors could do to improve how well libraries like egui work).

The suggested use for eframe are for web apps where performance and responsiveness are more important than accessibility and mobile text editing.

Companion crates

Not all rust crates work when compiled to WASM, but here are some useful crates have been designed to work well both natively and as WASM:

Name

The frame in eframe stands both for the frame in which your egui app resides and also for "framework" (frame is a framework, egui is a library).