Remove YAxisOrientation from bevy_text (#19077)

# Objective

Been looking for simplifications in the text systems as part of the text
input changes.

This enum isn't very helpful I think. We can remove it and the
associated parameters and instead just negate the glyph's y-offsets in
`extract_text2d_sprite`.

## Solution

Remove the `YAxisOrientation` enum and parameters. 
Queue text sprites relative to the top-left in `extract_text2d_sprite`
and negate the glyph's y-offset.

## Testing

The `text2d` example can be used for testing:
```
cargo run --example text2d
```

crates/bevy_text/src/lib.rs

@@ -87,18 +87,6 @@ pub const DEFAULT_FONT_DATA: &[u8] = include_bytes!("FiraMono-subset.ttf");
 #[derive(Default)]
 pub struct TextPlugin;
 
-/// Text is rendered for two different view projections;
-/// 2-dimensional text ([`Text2d`]) is rendered in "world space" with a `BottomToTop` Y-axis,
-/// while UI is rendered with a `TopToBottom` Y-axis.
-/// This matters for text because the glyph positioning is different in either layout.
-/// For `TopToBottom`, 0 is the top of the text, while for `BottomToTop` 0 is the bottom.
-pub enum YAxisOrientation {
-    /// Top to bottom Y-axis orientation, for UI
-    TopToBottom,
-    /// Bottom to top Y-axis orientation, for 2d world space
-    BottomToTop,
-}
-
 /// System set in [`PostUpdate`] where all 2d text update systems are executed.
 #[derive(Debug, Hash, PartialEq, Eq, Clone, SystemSet)]
 pub struct Text2dUpdateSystems;

crates/bevy_text/src/pipeline.rs

@@ -17,7 +17,7 @@ use cosmic_text::{Attrs, Buffer, Family, Metrics, Shaping, Wrap};
 
 use crate::{
     error::TextError, ComputedTextBlock, Font, FontAtlasSets, FontSmoothing, JustifyText,
-    LineBreak, PositionedGlyph, TextBounds, TextEntity, TextFont, TextLayout, YAxisOrientation,
+    LineBreak, PositionedGlyph, TextBounds, TextEntity, TextFont, TextLayout,
 };
 
 /// A wrapper resource around a [`cosmic_text::FontSystem`]
@@ -228,7 +228,6 @@ impl TextPipeline {
         font_atlas_sets: &mut FontAtlasSets,
         texture_atlases: &mut Assets<TextureAtlasLayout>,
         textures: &mut Assets<Image>,
-        y_axis_orientation: YAxisOrientation,
         computed: &mut ComputedTextBlock,
         font_system: &mut CosmicFontSystem,
         swash_cache: &mut SwashCache,
@@ -348,10 +347,6 @@ impl TextPipeline {
                     let x = glyph_size.x as f32 / 2.0 + left + physical_glyph.x as f32;
                     let y =
                         line_y.round() + physical_glyph.y as f32 - top + glyph_size.y as f32 / 2.0;
-                    let y = match y_axis_orientation {
-                        YAxisOrientation::TopToBottom => y,
-                        YAxisOrientation::BottomToTop => box_size.y - y,
-                    };
 
                     let position = Vec2::new(x, y);
 

crates/bevy_text/src/text2d.rs

@@ -2,7 +2,7 @@ use crate::pipeline::CosmicFontSystem;
 use crate::{
     ComputedTextBlock, Font, FontAtlasSets, LineBreak, PositionedGlyph, SwashCache, TextBounds,
     TextColor, TextError, TextFont, TextLayout, TextLayoutInfo, TextPipeline, TextReader, TextRoot,
-    TextSpanAccess, TextWriter, YAxisOrientation,
+    TextSpanAccess, TextWriter,
 };
 use bevy_asset::Assets;
 use bevy_color::LinearRgba;
@@ -182,10 +182,10 @@ pub fn extract_text2d_sprite(
             text_bounds.width.unwrap_or(text_layout_info.size.x),
             text_bounds.height.unwrap_or(text_layout_info.size.y),
         );
-        let bottom_left =
-            -(anchor.as_vec() + 0.5) * size + (size.y - text_layout_info.size.y) * Vec2::Y;
+
+        let top_left = (Anchor::TOP_LEFT.0 - anchor.as_vec()) * size;
         let transform =
-            *global_transform * GlobalTransform::from_translation(bottom_left.extend(0.)) * scaling;
+            *global_transform * GlobalTransform::from_translation(top_left.extend(0.)) * scaling;
         let mut color = LinearRgba::WHITE;
         let mut current_span = usize::MAX;
 
@@ -218,7 +218,7 @@ pub fn extract_text2d_sprite(
                 .textures[atlas_info.location.glyph_index]
                 .as_rect();
             extracted_slices.slices.push(ExtractedSlice {
-                offset: *position,
+                offset: Vec2::new(position.x, -position.y),
                 rect,
                 size: rect.size(),
             });
@@ -316,7 +316,6 @@ pub fn update_text2d_layout(
                 &mut font_atlas_sets,
                 &mut texture_atlases,
                 &mut textures,
-                YAxisOrientation::BottomToTop,
                 computed.as_mut(),
                 &mut font_system,
                 &mut swash_cache,

crates/bevy_ui/src/widget/text.rs

@@ -20,7 +20,7 @@ use bevy_reflect::{std_traits::ReflectDefault, Reflect};
 use bevy_text::{
     scale_value, ComputedTextBlock, CosmicFontSystem, Font, FontAtlasSets, LineBreak, SwashCache,
     TextBounds, TextColor, TextError, TextFont, TextLayout, TextLayoutInfo, TextMeasureInfo,
-    TextPipeline, TextReader, TextRoot, TextSpanAccess, TextWriter, YAxisOrientation,
+    TextPipeline, TextReader, TextRoot, TextSpanAccess, TextWriter,
 };
 use taffy::style::AvailableSpace;
 use tracing::error;
@@ -328,7 +328,6 @@ fn queue_text(
         font_atlas_sets,
         texture_atlases,
         textures,
-        YAxisOrientation::TopToBottom,
         computed,
         font_system,
         swash_cache,