Files
ruin/lib/ui/src/scene.rs

904 lines
28 KiB
Rust

//! Renderer-oriented scene snapshot types.
use std::ops::{Deref, Range};
use std::sync::Arc;
use cosmic_text::CacheKey;
use tracing::debug;
use crate::ImageResource;
use crate::text::TextSelectionStyle;
use crate::trace_targets;
use crate::tree::{BoxShadowKind, ElementId};
pub type SceneVersion = u64;
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct Point {
pub x: f32,
pub y: f32,
}
impl Point {
pub const fn new(x: f32, y: f32) -> Self {
Self { x, y }
}
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct UiSize {
pub width: f32,
pub height: f32,
}
impl UiSize {
pub const fn new(width: f32, height: f32) -> Self {
Self { width, height }
}
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct Rect {
pub origin: Point,
pub size: UiSize,
}
impl Rect {
pub const fn new(x: f32, y: f32, width: f32, height: f32) -> Self {
Self {
origin: Point::new(x, y),
size: UiSize::new(width, height),
}
}
pub fn contains(self, point: Point) -> bool {
point.x >= self.origin.x
&& point.y >= self.origin.y
&& point.x < self.origin.x + self.size.width
&& point.y < self.origin.y + self.size.height
}
pub fn intersects(self, other: Rect) -> bool {
self.origin.x < other.origin.x + other.size.width
&& self.origin.x + self.size.width > other.origin.x
&& self.origin.y < other.origin.y + other.size.height
&& self.origin.y + self.size.height > other.origin.y
}
}
#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
pub struct Color {
pub r: u8,
pub g: u8,
pub b: u8,
pub a: u8,
}
impl Color {
/// Sentinel value meaning "use the PreparedText default_color at render time".
/// Fully transparent black (a == 0) is never a useful visible color, so it is
/// safe to reserve as a sentinel. No user-facing API sets this value directly.
pub const SENTINEL: Self = Self::rgba(0, 0, 0, 0);
pub const fn rgba(r: u8, g: u8, b: u8, a: u8) -> Self {
Self { r, g, b, a }
}
pub const fn rgb(r: u8, g: u8, b: u8) -> Self {
Self::rgba(r, g, b, 255)
}
/// Returns `true` when this color is the sentinel "use default" marker.
#[inline]
pub const fn is_sentinel(self) -> bool {
self.a == 0
}
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct Translation {
pub x: f32,
pub y: f32,
}
impl Translation {
pub const fn new(x: f32, y: f32) -> Self {
Self { x, y }
}
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct Quad {
pub rect: Rect,
pub color: Color,
}
impl Quad {
pub const fn new(rect: Rect, color: Color) -> Self {
Self { rect, color }
}
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct RoundedRect {
pub rect: Rect,
pub fill: Option<Color>,
pub border_color: Option<Color>,
pub border_width: f32,
pub radius: f32,
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct ShadowRect {
pub rect: Rect,
pub source_rect: Rect,
pub color: Color,
pub blur: f32,
pub radius: f32,
pub source_radius: f32,
pub kind: BoxShadowKind,
}
#[derive(Clone, Copy, Debug, PartialEq)]
pub struct ClipRegion {
pub rect: Rect,
pub radius: f32,
}
#[derive(Clone, Debug, PartialEq)]
pub struct GlyphInstance {
pub position: Point,
pub advance: f32,
/// Glyph color. When equal to `Color::SENTINEL` the renderer uses the
/// enclosing `PreparedText::default_color`. This allows the text layout
/// cache to be color-independent: the same shaped data can be reused for
/// the same text displayed in different colors.
pub color: Color,
pub cache_key: Option<CacheKey>,
pub text_start: usize,
pub text_end: usize,
}
#[derive(Clone, Debug, PartialEq)]
pub struct PreparedTextLine {
pub rect: Rect,
pub text_start: usize,
pub text_end: usize,
pub glyph_start: usize,
pub glyph_end: usize,
}
/// Shaped, positioned text ready for rendering.
///
/// Glyphs and line rects are stored in **local (origin-relative) coordinates**:
/// add `self.origin` to convert to absolute window coords. This keeps the
/// `Arc<TextLayoutData>` from the text shape cache shareable across different
/// on-screen positions — no per-frame translation is required.
///
/// The `lines` and `glyphs` are stored behind an `Arc` so that cloning a
/// `PreparedText` (e.g. to put the same shaped text into both the scene
/// snapshot and the interaction tree) is O(1). The `Arc` is shared as long
/// as no mutation is needed; `apply_selected_text_color` uses
/// `Arc::make_mut` and clones on first write.
///
/// Glyph colors may be `Color::SENTINEL` — the renderer substitutes
/// `default_color` for those glyphs.
#[derive(Clone, Debug, PartialEq)]
pub struct PreparedText {
pub element_id: Option<ElementId>,
pub text: String,
pub origin: Point,
pub bounds: Option<UiSize>,
pub font_size: f32,
pub line_height: f32,
/// Default color applied to sentinel-colored glyphs at render time.
pub default_color: Color,
pub selectable: bool,
pub selection_style: TextSelectionStyle,
layout: Arc<TextLayoutData>,
}
/// Shaped glyph and line data shared between scene and interaction-tree copies
/// of the same `PreparedText`. Coordinates are LOCAL (relative to `PreparedText::origin`).
/// Add `origin` to convert to absolute window coords.
#[derive(Clone, Debug, PartialEq)]
pub struct TextLayoutData {
pub lines: Vec<PreparedTextLine>,
pub glyphs: Vec<GlyphInstance>,
/// Measured (unclamped) size of the laid-out text.
pub size: UiSize,
}
impl Deref for PreparedText {
type Target = TextLayoutData;
fn deref(&self) -> &TextLayoutData {
&self.layout
}
}
impl PreparedText {
/// Construct a `PreparedText` from shaped data. Called by `TextSystem::prepare_spans`.
pub(crate) fn from_layout(
element_id: Option<ElementId>,
text: String,
origin: Point,
bounds: Option<UiSize>,
font_size: f32,
line_height: f32,
default_color: Color,
selectable: bool,
selection_style: TextSelectionStyle,
layout: Arc<TextLayoutData>,
) -> Self {
Self {
element_id,
text,
origin,
bounds,
font_size,
line_height,
default_color,
selectable,
selection_style,
layout,
}
}
/// Returns a raw pointer to the underlying `TextLayoutData` allocation.
/// Used in tests to verify Arc sharing between PreparedTexts.
#[cfg(test)]
pub(crate) fn layout_ptr(&self) -> *const TextLayoutData {
Arc::as_ptr(&self.layout)
}
/// Create a monospace `PreparedText` without going through the text system.
/// Used for testing and low-level terminal-style rendering.
pub fn monospace(
text: impl Into<String>,
origin: Point,
font_size: f32,
advance: f32,
color: Color,
) -> Self {
let text = text.into();
// Glyphs are stored in LOCAL (origin-relative) coordinates.
let mut local_x = 0.0f32;
let mut glyphs = Vec::with_capacity(text.chars().count());
for (text_start, ch) in text.char_indices() {
let text_end = text_start + ch.len_utf8();
// monospace() builds glyphs directly; use the actual color (not sentinel)
// because this path does not go through the text cache.
glyphs.push(GlyphInstance {
position: Point::new(local_x, 0.0),
advance,
color,
cache_key: None,
text_start,
text_end,
});
local_x += advance;
}
let line = PreparedTextLine {
rect: Rect::new(0.0, 0.0, local_x, font_size),
text_start: 0,
text_end: glyphs.last().map_or(0, |glyph| glyph.text_end),
glyph_start: 0,
glyph_end: glyphs.len(),
};
let size = UiSize::new(local_x, font_size);
Self {
element_id: None,
text,
origin,
bounds: None,
font_size,
line_height: font_size,
default_color: color,
selectable: true,
selection_style: TextSelectionStyle::DEFAULT,
layout: Arc::new(TextLayoutData {
lines: vec![line],
glyphs,
size,
}),
}
}
/// Translate this text by `offset`. O(1): only `self.origin` is updated.
/// Glyphs are stored in local coords and are unaffected.
pub fn translated(mut self, offset: Point) -> Self {
self.origin.x += offset.x;
self.origin.y += offset.y;
self
}
/// Return the byte offset within `self.text` for an absolute window-space point.
pub fn byte_offset_for_position(&self, point: Point) -> usize {
// Convert to local coords before delegating to the local-space helpers.
let local_x = point.x - self.origin.x;
let local_y = point.y - self.origin.y;
let Some(line) = self.line_for_position(local_y) else {
return 0;
};
self.byte_offset_for_line_position(line, local_x)
}
pub fn selection_range(&self, start: usize, end: usize) -> Range<usize> {
let start = start.min(self.text.len());
let end = end.min(self.text.len());
if start <= end { start..end } else { end..start }
}
pub fn selected_text(&self, start: usize, end: usize) -> Option<&str> {
let range = self.selection_range(start, end);
self.text.get(range)
}
pub fn selection_rects(&self, start: usize, end: usize) -> Vec<Rect> {
let range = self.selection_range(start, end);
if range.is_empty() {
return Vec::new();
}
let mut rects = Vec::new();
for line in &self.lines {
let mut left = None::<f32>;
let mut right = None::<f32>;
for glyph in &self.glyphs[line.glyph_start..line.glyph_end] {
if glyph.text_end <= range.start || glyph.text_start >= range.end {
continue;
}
let glyph_left = glyph.position.x;
let glyph_right = glyph.position.x + glyph.advance.max(0.0);
left = Some(left.map_or(glyph_left, |current| current.min(glyph_left)));
right = Some(right.map_or(glyph_right, |current| current.max(glyph_right)));
}
if let (Some(left), Some(right)) = (left, right) {
// Glyph x/y and line rect are in local coords; add origin for absolute result.
rects.push(Rect::new(
self.origin.x + left,
self.origin.y + line.rect.origin.y,
(right - left).max(0.0),
line.rect.size.height,
));
}
}
rects
}
pub fn caret_rect(&self, offset: usize, width: f32) -> Option<Rect> {
let width = width.max(0.0);
let line = self.line_for_offset(offset)?;
// caret_x_for_line_offset returns local x; add origin for absolute result.
let local_x = self.caret_x_for_line_offset(line, offset);
Some(Rect::new(
self.origin.x + local_x,
self.origin.y + line.rect.origin.y,
width,
line.rect.size.height,
))
}
pub fn previous_char_boundary(&self, offset: usize) -> usize {
let offset = offset.min(self.text.len());
self.text[..offset]
.char_indices()
.last()
.map(|(index, _)| index)
.unwrap_or(0)
}
pub fn next_char_boundary(&self, offset: usize) -> usize {
let offset = offset.min(self.text.len());
if offset >= self.text.len() {
return self.text.len();
}
self.text
.char_indices()
.find_map(|(index, _)| (index > offset).then_some(index))
.unwrap_or(self.text.len())
}
pub fn line_start_offset(&self, offset: usize) -> Option<usize> {
Some(self.line_for_offset(offset)?.text_start)
}
pub fn line_end_offset(&self, offset: usize) -> Option<usize> {
Some(self.line_for_offset(offset)?.text_end)
}
pub fn vertical_offset(&self, offset: usize, line_delta: isize) -> Option<usize> {
if line_delta == 0 {
return Some(offset.min(self.text.len()));
}
let offset = offset.min(self.text.len());
let line = self.line_for_offset(offset)?;
let current_index = self.lines.iter().position(|candidate| candidate == line)?;
let next_index = current_index.checked_add_signed(line_delta)?;
let next_line = self.lines.get(next_index)?;
let target_x = self.caret_x_for_line_offset(line, offset);
Some(self.byte_offset_for_line_position(next_line, target_x))
}
pub fn word_range_for_offset(&self, offset: usize) -> Range<usize> {
if self.text.is_empty() {
return 0..0;
}
let offset = offset.min(self.text.len());
let target = self.word_class_offset(offset);
let Some((target_start, target_ch)) = self.char_at(target) else {
return 0..self.text.len();
};
let target_class = classify_word_char(target_ch);
let mut start = target_start;
while let Some((previous_start, previous_ch)) = self.char_before(start) {
if classify_word_char(previous_ch) != target_class {
break;
}
start = previous_start;
}
let mut end = target_start + target_ch.len_utf8();
while let Some((next_start, next_ch)) = self.char_at(end) {
if classify_word_char(next_ch) != target_class {
break;
}
end = next_start + next_ch.len_utf8();
}
start..end
}
/// Apply `selection_style.text_color` to glyphs in `[start, end)`.
/// Clones the inner `Arc<TextLayoutData>` on first call if it is shared.
pub fn apply_selected_text_color(&mut self, start: usize, end: usize) {
let Some(selected_color) = self.selection_style.text_color else {
return;
};
let range = self.selection_range(start, end);
if range.is_empty() {
return;
}
for glyph in Arc::make_mut(&mut self.layout).glyphs.iter_mut() {
if glyph.text_end > range.start && glyph.text_start < range.end {
glyph.color = selected_color;
}
}
}
fn line_for_position(&self, y: f32) -> Option<&PreparedTextLine> {
let mut lines = self.lines.iter();
let first = lines.next()?;
if y < first.rect.origin.y {
return Some(first);
}
let mut last = first;
for line in std::iter::once(first).chain(lines) {
last = line;
if y < line.rect.origin.y + line.rect.size.height {
return Some(line);
}
}
Some(last)
}
fn line_for_offset(&self, offset: usize) -> Option<&PreparedTextLine> {
let offset = offset.min(self.text.len());
let mut lines = self.lines.iter();
let first = lines.next()?;
for line in std::iter::once(first).chain(lines) {
if offset <= line.text_end {
return Some(line);
}
}
Some(self.lines.last().unwrap_or(first))
}
fn byte_offset_for_line_position(&self, line: &PreparedTextLine, x: f32) -> usize {
if line.glyph_start == line.glyph_end {
return line.text_start;
}
let line_glyphs = &self.glyphs[line.glyph_start..line.glyph_end];
let first_glyph = &line_glyphs[0];
if x <= first_glyph.position.x {
return first_glyph.text_start;
}
for glyph in line_glyphs {
let glyph_left = glyph.position.x;
let glyph_right = glyph.position.x + glyph.advance.max(0.0);
let midpoint = glyph_left + glyph.advance.max(0.0) * 0.5;
if x < midpoint {
return glyph.text_start;
}
if x < glyph_right {
return glyph.text_end;
}
}
line.text_end
}
fn caret_x_for_line_offset(&self, line: &PreparedTextLine, offset: usize) -> f32 {
if line.glyph_start == line.glyph_end {
return line.rect.origin.x;
}
let offset = offset.min(self.text.len());
let line_glyphs = &self.glyphs[line.glyph_start..line.glyph_end];
let first_glyph = &line_glyphs[0];
if offset <= first_glyph.text_start {
return first_glyph.position.x;
}
for glyph in line_glyphs {
if offset <= glyph.text_start {
return glyph.position.x;
}
if offset <= glyph.text_end {
return glyph.position.x + glyph.advance.max(0.0);
}
}
line_glyphs
.last()
.map(|glyph| glyph.position.x + glyph.advance.max(0.0))
.unwrap_or(line.rect.origin.x)
}
fn char_at(&self, offset: usize) -> Option<(usize, char)> {
if offset >= self.text.len() {
return None;
}
self.text[offset..].chars().next().map(|ch| (offset, ch))
}
fn char_before(&self, offset: usize) -> Option<(usize, char)> {
let offset = offset.min(self.text.len());
self.text[..offset].char_indices().last()
}
fn word_class_offset(&self, offset: usize) -> usize {
if offset >= self.text.len() {
return self.previous_char_boundary(offset);
}
if offset > 0
&& let (Some((_, previous)), Some((_, current))) =
(self.char_before(offset), self.char_at(offset))
&& classify_word_char(current) == WordClass::Whitespace
&& classify_word_char(previous) == WordClass::Word
{
return self.previous_char_boundary(offset);
}
offset
}
}
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
enum WordClass {
Word,
Whitespace,
Punctuation,
}
fn classify_word_char(ch: char) -> WordClass {
if ch.is_whitespace() {
WordClass::Whitespace
} else if ch.is_alphanumeric() || ch == '_' {
WordClass::Word
} else {
WordClass::Punctuation
}
}
#[derive(Clone, Debug, PartialEq)]
pub struct PreparedImage {
pub element_id: Option<ElementId>,
pub resource: ImageResource,
pub rect: Rect,
pub uv_rect: (f32, f32, f32, f32),
}
#[derive(Clone, Debug, PartialEq)]
pub enum DisplayItem {
Quad(Quad),
RoundedRect(RoundedRect),
ShadowRect(ShadowRect),
Image(PreparedImage),
Text(PreparedText),
PushClip(ClipRegion),
PopClip,
PushTransform(Translation),
PopTransform,
LayerBegin { opacity: f32 },
LayerEnd,
}
impl DisplayItem {
/// Return a copy of this item with all positions shifted by `offset`.
pub fn translated(&self, offset: Point) -> Self {
fn translate_rect(r: Rect, o: Point) -> Rect {
Rect::new(r.origin.x + o.x, r.origin.y + o.y, r.size.width, r.size.height)
}
match self {
Self::Quad(q) => Self::Quad(Quad { rect: translate_rect(q.rect, offset), ..*q }),
Self::RoundedRect(r) => Self::RoundedRect(RoundedRect {
rect: translate_rect(r.rect, offset),
..*r
}),
Self::ShadowRect(s) => Self::ShadowRect(ShadowRect {
rect: translate_rect(s.rect, offset),
source_rect: translate_rect(s.source_rect, offset),
..*s
}),
Self::Image(img) => Self::Image(PreparedImage {
rect: translate_rect(img.rect, offset),
..img.clone()
}),
Self::Text(text) => Self::Text(text.clone().translated(offset)),
Self::PushClip(clip) => Self::PushClip(ClipRegion {
rect: translate_rect(clip.rect, offset),
..*clip
}),
// These items carry no position data or are balanced markers.
Self::PopClip => Self::PopClip,
Self::PushTransform(t) => Self::PushTransform(*t),
Self::PopTransform => Self::PopTransform,
Self::LayerBegin { opacity } => Self::LayerBegin { opacity: *opacity },
Self::LayerEnd => Self::LayerEnd,
}
}
}
#[derive(Clone, Debug, PartialEq)]
pub struct SceneSnapshot {
pub version: SceneVersion,
pub logical_size: UiSize,
pub items: Vec<DisplayItem>,
}
impl SceneSnapshot {
pub fn new(version: SceneVersion, logical_size: UiSize) -> Self {
debug!(
target: trace_targets::SCENE,
event = "create_scene",
version,
width = logical_size.width,
height = logical_size.height,
"creating scene snapshot"
);
Self {
version,
logical_size,
items: Vec::new(),
}
}
pub fn item_count(&self) -> usize {
self.items.len()
}
pub fn push_item(&mut self, item: DisplayItem) -> &mut Self {
self.items.push(item);
self
}
pub fn push_quad(&mut self, rect: Rect, color: Color) -> &mut Self {
self.push_item(DisplayItem::Quad(Quad::new(rect, color)))
}
pub fn push_rounded_rect(&mut self, rounded_rect: RoundedRect) -> &mut Self {
self.push_item(DisplayItem::RoundedRect(rounded_rect))
}
pub fn push_shadow_rect(&mut self, shadow_rect: ShadowRect) -> &mut Self {
self.push_item(DisplayItem::ShadowRect(shadow_rect))
}
pub fn push_text(&mut self, text: PreparedText) -> &mut Self {
self.push_item(DisplayItem::Text(text))
}
pub fn push_image(&mut self, image: PreparedImage) -> &mut Self {
self.push_item(DisplayItem::Image(image))
}
pub fn push_clip(&mut self, rect: Rect, radius: f32) -> &mut Self {
self.push_item(DisplayItem::PushClip(ClipRegion { rect, radius }))
}
pub fn pop_clip(&mut self) -> &mut Self {
self.push_item(DisplayItem::PopClip)
}
pub fn push_transform(&mut self, translation: Translation) -> &mut Self {
self.push_item(DisplayItem::PushTransform(translation))
}
pub fn pop_transform(&mut self) -> &mut Self {
self.push_item(DisplayItem::PopTransform)
}
pub fn begin_layer(&mut self, opacity: f32) -> &mut Self {
self.push_item(DisplayItem::LayerBegin { opacity })
}
pub fn end_layer(&mut self) -> &mut Self {
self.push_item(DisplayItem::LayerEnd)
}
}
// ---------------------------------------------------------------------------
// Hash implementations for f32-containing types.
impl std::hash::Hash for Point {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
self.x.to_bits().hash(state);
self.y.to_bits().hash(state);
}
}
impl std::hash::Hash for UiSize {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
self.width.to_bits().hash(state);
self.height.to_bits().hash(state);
}
}
#[cfg(test)]
mod tests {
use super::{Color, Point, PreparedText, Rect};
use crate::TextSelectionStyle;
use crate::{TextStyle, TextSystem, TextWrap};
#[test]
fn prepared_text_hit_testing_clamps_to_nearest_cluster_boundary() {
let text = PreparedText::monospace(
"abcd",
Point::new(10.0, 20.0),
16.0,
8.0,
Color::rgb(0xFF, 0xFF, 0xFF),
);
assert_eq!(text.byte_offset_for_position(Point::new(6.0, 24.0)), 0);
assert_eq!(text.byte_offset_for_position(Point::new(13.0, 24.0)), 0);
assert_eq!(text.byte_offset_for_position(Point::new(17.0, 24.0)), 1);
assert_eq!(text.byte_offset_for_position(Point::new(33.0, 24.0)), 3);
assert_eq!(text.byte_offset_for_position(Point::new(50.0, 24.0)), 4);
}
#[test]
fn prepared_text_selection_rects_cover_selected_glyphs() {
let mut text = PreparedText::monospace(
"abcd",
Point::new(10.0, 20.0),
16.0,
8.0,
Color::rgb(0xFF, 0xFF, 0xFF),
);
text.selection_style = TextSelectionStyle::new(Color::rgba(0x44, 0x66, 0xFF, 0xAA))
.with_text_color(Color::rgb(0x11, 0x12, 0x1A));
assert_eq!(
text.selection_rects(1, 3),
vec![Rect::new(18.0, 20.0, 16.0, 16.0)]
);
assert_eq!(text.selected_text(1, 3), Some("bc"));
text.apply_selected_text_color(1, 3);
assert_eq!(text.glyphs[0].color, Color::rgb(0xFF, 0xFF, 0xFF));
assert_eq!(text.glyphs[1].color, Color::rgb(0x11, 0x12, 0x1A));
assert_eq!(text.glyphs[2].color, Color::rgb(0x11, 0x12, 0x1A));
}
#[test]
fn prepared_text_caret_rect_tracks_cluster_boundaries() {
let text = PreparedText::monospace(
"abcd",
Point::new(10.0, 20.0),
16.0,
8.0,
Color::rgb(0xFF, 0xFF, 0xFF),
);
assert_eq!(
text.caret_rect(0, 2.0),
Some(Rect::new(10.0, 20.0, 2.0, 16.0))
);
assert_eq!(
text.caret_rect(2, 2.0),
Some(Rect::new(26.0, 20.0, 2.0, 16.0))
);
assert_eq!(
text.caret_rect(4, 2.0),
Some(Rect::new(42.0, 20.0, 2.0, 16.0))
);
}
#[test]
fn prepared_text_word_range_tracks_words_and_punctuation() {
let text = PreparedText::monospace(
"alpha beta, gamma",
Point::new(10.0, 20.0),
16.0,
8.0,
Color::rgb(0xFF, 0xFF, 0xFF),
);
assert_eq!(text.word_range_for_offset(1), 0..5);
assert_eq!(text.word_range_for_offset(6), 6..10);
assert_eq!(text.word_range_for_offset(10), 10..11);
assert_eq!(text.word_range_for_offset(text.text.len()), 12..17);
}
#[test]
fn prepared_text_vertical_offset_moves_between_lines() {
use std::sync::Arc;
use super::{PreparedTextLine, TextLayoutData};
let mut text = PreparedText::monospace(
"abcdwxyz",
Point::new(10.0, 20.0),
16.0,
8.0,
Color::rgb(0xFF, 0xFF, 0xFF),
);
// Lines and glyphs use LOCAL (origin-relative) coordinates.
let lines = vec![
PreparedTextLine {
rect: Rect::new(0.0, 0.0, 32.0, 16.0),
text_start: 0,
text_end: 4,
glyph_start: 0,
glyph_end: 4,
},
PreparedTextLine {
rect: Rect::new(0.0, 16.0, 32.0, 16.0),
text_start: 4,
text_end: 8,
glyph_start: 4,
glyph_end: 8,
},
];
let mut glyphs = text.glyphs.to_vec();
for (index, glyph) in glyphs.iter_mut().enumerate() {
if index >= 4 {
glyph.position.y = 16.0;
glyph.position.x = (index - 4) as f32 * 8.0;
}
}
let orig_size = text.layout.size;
text.layout = Arc::new(TextLayoutData { lines, glyphs, size: orig_size });
assert_eq!(text.vertical_offset(2, 1), Some(6));
assert_eq!(text.vertical_offset(6, -1), Some(2));
assert_eq!(text.line_start_offset(6), Some(4));
assert_eq!(text.line_end_offset(2), Some(4));
}
#[test]
fn prepared_text_multiline_selection_stays_on_target_line() {
let mut text_system = TextSystem::new();
let style = TextStyle::new(16.0, Color::rgb(0xFF, 0xFF, 0xFF)).with_wrap(TextWrap::None);
let text = text_system.prepare("ab\ncd\nef", Point::new(10.0, 20.0), &style);
assert_eq!(text.lines.len(), 3);
let target_line = &text.lines[1];
// Lines store LOCAL coords; add text.origin to get absolute window coords for the query.
let y = text.origin.y + target_line.rect.origin.y + target_line.rect.size.height * 0.5;
let start = text.byte_offset_for_position(Point::new(text.origin.x + target_line.rect.origin.x, y));
let end = text.byte_offset_for_position(Point::new(text.origin.x + target_line.rect.origin.x + 16.0, y));
let rects = text.selection_rects(start, end);
assert_eq!(rects.len(), 1);
// selection_rects returns absolute coords; compare against absolute line y.
assert_eq!(rects[0].origin.y, text.origin.y + target_line.rect.origin.y);
}
}