The LogPlugin now allows overriding the default
`tracing_subscriber::fmt::Layer` through a new `fmt_layer` option. This
enables customization of the default log output format without having to
replace the entire logging system.
For example, to disable timestamps in the log output:
```rust
fn fmt_layer(_app: &mut App) -> Option<bevy::log::BoxedFmtLayer> {
Some(Box::new(
bevy::log::tracing_subscriber::fmt::Layer::default()
.without_time()
.with_writer(std::io::stderr),
))
}
fn main() {
App::new()
.add_plugins(DefaultPlugins.set(bevy::log::LogPlugin {
fmt_layer,
..default()
}))
.run();
}
```
This is different from the existing `custom_layer` option, because that
option _adds_ additional layers to the subscriber, but can't modify the
default formatter layer (at least, not to my knowledge).
I almost always disable timestamps in my Bevy logs, and usually also
tweak other default log formatting (such as `with_span_events`), which
made it so that I always had to disable the default logger. This allows
me to use everything the Bevy logger supports (including tracy support),
while still formatting the default logs the way I like them.
---------
Signed-off-by: Jean Mertz <git@jeanmertz.com>
3b24f520b9