How to use multiple cameras in bevy 0.5.0?

Question

I have a simple bevy test app, that displays an array of cubes and an FPS counter in the upper left corner. The 3d scene can be zoomed and rotated.

I recently tried to upgrade the following code to bevy = 0.5.0.

Old code block (bevy = 0.4.0):

commands.spawn(LightBundle {
            transform: Transform::from_translation(Vec3::new(4.0, 8.0, 4.0)),
            ..Default::default()
        })
        .spawn(Camera3dBundle {
            transform: Transform::from_translation(Vec3::new(0.0, 0.0, 10 as f32 * 1.25))
                .looking_at(Vec3::default(), Vec3::unit_y()),
            ..Default::default()
        })
        .with(OrbitCamera::new(0.0, 0.0, 10 as f32 * 1.25, Vec3::zero()));

commands.spawn(CameraUiBundle::default())
    // texture
    .spawn(TextBundle {
        transform: Transform::from_translation(Vec3::new(0.0, 0.0, 0.0)),
        style: Style {
            align_self: AlignSelf::FlexEnd,
            ..Default::default()
        },
        text: Text {
            value: " FPS:".to_string(),
            font: asset_server.load("fonts/FiraSans-Bold.ttf"),
            style: TextStyle {
                font_size: 20.0,
                color: Color::WHITE,
                ..Default::default()
            },
        },
        ..Default::default()
    })
    .with(FpsText);

The reason I spawned the TextBundle in a separate camera, was that I wanted it to be stationary and not react to any camera transformations.

I tried to replicate that behaviour in bevy = 0.5.0 like this:

commands.spawn_bundle(LightBundle {
    transform: Transform::from_translation(Vec3::new(4.0, 8.0, 4.0)),
    ..Default::default()
});

commands.spawn_bundle(PerspectiveCameraBundle {
    transform: Transform::from_translation(Vec3::new(0.0, 0.0, 10 as f32 * 1.25)).looking_at(Vec3::default(), Vec3::Y),
    ..Default::default()
})
.insert(OrbitCamera::new(0.0, 0.0, 10 as f32 * 1.25, Vec3::ZERO));

commands.spawn_bundle(UiCameraBundle::default())
.insert_bundle(Text2dBundle {
    text: Text::with_section(
        " FPS:",
        TextStyle {
            font: asset_server.load("fonts/FiraSans-Bold.ttf"),
            font_size: 20.0,
            color: Color::WHITE,
        },
        TextAlignment {
            vertical: VerticalAlign::Top,
            horizontal: HorizontalAlign::Left,
        },
    ),
    ..Default::default()
})
.insert(FpsText);

Everything works as expected again, except the FPS Text is not in the upper left corner of the window anymore and is now rotated and scaled like the cubes in the scene, too (which I don't want to happen).

How can I replicate the old behaviour in bevy = 0.5.0, so that the Text is rendered as a stationary overlay?

The full code for both versions can be found on Github here (0.4.0) and here (0.5.0).

score 1 · Accepted Answer · answered Apr 29 '21 at 22:52

1

Text2dBundle is associated with the regular camera. If you want text associated with the UI camera, you need to use TextBundle instead. You will also need to set the Style component on the TextBundle in order to control its position so that it's visible on screen.

Your bevy 0.4 code fragment was using TextBundle successfully, so this just needs porting more faithfully.

answered Apr 29 '21 at 22:52

komadori

126
1
3

Thanks for this, it helped me a bit. Unfortunately it seems, that when I use `TextBundle` I can not use the Style to control the position of the text inside the window. The text is always in the lower left corner no matter what position I put into the Style... – frankenapps May 01 '21 at 08:57
Nevermind. I initially used `commands.spawn_bundle(UiCameraBundle::default()).insert_bundle(TextBundle{...});`but it works as expected using `commands.spawn_bundle(UiCameraBundle::default());` and `commands.spawn_bundle(TextBundle{...});` – frankenapps May 01 '21 at 09:06

How to use multiple cameras in bevy 0.5.0?

1 Answers1