# Objective
Cleanup naming and docs, add missing migration guide after #15591
All text root nodes now use `Text` (UI) / `Text2d`.
All text readers/writers use `Text<Type>Reader`/`Text<Type>Writer`
convention.
---
## Migration Guide
Doubles as #15591 migration guide.
Text bundles (`TextBundle` and `Text2dBundle`) were removed in favor of
`Text` and `Text2d`.
Shared configuration fields were replaced with `TextLayout`, `TextFont`
and `TextColor` components.
Just `TextBundle`'s additional field turned into `TextNodeFlags`
component,
while `Text2dBundle`'s additional fields turned into `TextBounds` and
`Anchor` components.
Text sections were removed in favor of hierarchy-based approach.
For root text entities with `Text` or `Text2d` components, child
entities with `TextSpan` will act as additional text sections.
To still access text spans by index, use the new `TextUiReader`,
`Text2dReader` and `TextUiWriter`, `Text2dWriter` system parameters.
# Objective
- closes#15866
## Solution
- Simply migrate where possible.
## Testing
- Expect that CI will do most of the work. Examples is another way of
testing this, as most of the work is in that area.
---
## Notes
For now, this PR doesn't migrate `QueryState::single` and friends as for
now, this look like another issue. So for example, QueryBuilders that
used single or `World::query` that used single wasn't migrated. If there
is a easy way to migrate those, please let me know.
Most of the uses of `Query::single` were removed, the only other uses
that I found was related to tests of said methods, so will probably be
removed when we remove `Query::single`.
**Ready for review. Examples migration progress: 100%.**
# Objective
- Implement https://github.com/bevyengine/bevy/discussions/15014
## Solution
This implements [cart's
proposal](https://github.com/bevyengine/bevy/discussions/15014#discussioncomment-10574459)
faithfully except for one change. I separated `TextSpan` from
`TextSpan2d` because `TextSpan` needs to require the `GhostNode`
component, which is a `bevy_ui` component only usable by UI.
Extra changes:
- Added `EntityCommands::commands_mut` that returns a mutable reference.
This is a blocker for extension methods that return something other than
`self`. Note that `sickle_ui`'s `UiBuilder::commands` returns a mutable
reference for this reason.
## Testing
- [x] Text examples all work.
---
## Showcase
TODO: showcase-worthy
## Migration Guide
TODO: very breaking
### Accessing text spans by index
Text sections are now text sections on different entities in a
hierarchy, Use the new `TextReader` and `TextWriter` system parameters
to access spans by index.
Before:
```rust
fn refresh_text(mut query: Query<&mut Text, With<TimeText>>, time: Res<Time>) {
let text = query.single_mut();
text.sections[1].value = format_time(time.elapsed());
}
```
After:
```rust
fn refresh_text(
query: Query<Entity, With<TimeText>>,
mut writer: UiTextWriter,
time: Res<Time>
) {
let entity = query.single();
*writer.text(entity, 1) = format_time(time.elapsed());
}
```
### Iterating text spans
Text spans are now entities in a hierarchy, so the new `UiTextReader`
and `UiTextWriter` system parameters provide ways to iterate that
hierarchy. The `UiTextReader::iter` method will give you a normal
iterator over spans, and `UiTextWriter::for_each` lets you visit each of
the spans.
---------
Co-authored-by: ickshonpe <david.curthoys@googlemail.com>
Co-authored-by: Carter Anderson <mcanders1@gmail.com>
# Objective
- Alpha blending can easily fail in many situations and requires sorting
on the cpu
## Solution
- Implement order independent transparency (OIT) as an alternative to
alpha blending
- The implementation uses 2 passes
- The first pass records all the fragments colors and position to a
buffer that is the size of N layers * the render target resolution.
- The second pass sorts the fragments, blends them and draws them to the
screen. It also currently does manual depth testing because early-z
fails in too many cases in the first pass.
## Testing
- We've been using this implementation at foresight in production for
many months now and we haven't had any issues related to OIT.
---
## Showcase
## Future work
- Add an example showing how to use OIT for a custom material
- Next step would be to implement a per-pixel linked list to reduce
memory use
- I'd also like to investigate using a BinnedRenderPhase instead of a
SortedRenderPhase. If it works, it would make the transparent pass
significantly faster.
---------
Co-authored-by: Kristoffer Søholm <k.soeholm@gmail.com>
Co-authored-by: JMS55 <47158642+JMS55@users.noreply.github.com>
Co-authored-by: Charlotte McElwain <charlotte.c.mcelwain@gmail.com>
