mirror of https://github.com/TaKO8Ki/gobang
editor
Takayuki Maeda
3 years ago
parent
73287632c8
commit
955abdcd07
@ -0,0 +1,535 @@
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use easy_cast::Cast;
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use tui::text::StyledGrapheme;
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use unicode_segmentation::UnicodeSegmentation;
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use unicode_width::UnicodeWidthStr;
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const NBSP: &str = "\u{00a0}";
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/// A state machine to pack styled symbols into lines.
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/// Cannot implement it as Iterator since it yields slices of the internal buffer (need streaming
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/// iterators for that).
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pub trait LineComposer<'a> {
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fn next_line(&mut self) -> Option<(&[StyledGrapheme<'a>], u16)>;
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}
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/// A state machine that wraps lines on word boundaries.
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pub struct WordWrapper<'a, 'b> {
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symbols: &'b mut dyn Iterator<Item = StyledGrapheme<'a>>,
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max_line_width: u16,
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current_line: Vec<StyledGrapheme<'a>>,
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next_line: Vec<StyledGrapheme<'a>>,
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/// Removes the leading whitespace from lines
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trim: bool,
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}
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impl<'a, 'b> WordWrapper<'a, 'b> {
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pub fn new(
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symbols: &'b mut dyn Iterator<Item = StyledGrapheme<'a>>,
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max_line_width: u16,
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trim: bool,
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) -> WordWrapper<'a, 'b> {
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WordWrapper {
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symbols,
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max_line_width,
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current_line: vec![],
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next_line: vec![],
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trim,
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}
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}
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}
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impl<'a, 'b> LineComposer<'a> for WordWrapper<'a, 'b> {
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fn next_line(&mut self) -> Option<(&[StyledGrapheme<'a>], u16)> {
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if self.max_line_width == 0 {
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return None;
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}
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std::mem::swap(&mut self.current_line, &mut self.next_line);
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self.next_line.truncate(0);
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let mut current_line_width = self
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.current_line
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.iter()
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.map(|StyledGrapheme { symbol, .. }| -> u16 { symbol.width().cast() })
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.sum();
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let mut symbols_to_last_word_end: usize = 0;
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let mut width_to_last_word_end: u16 = 0;
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let mut prev_whitespace = false;
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let mut symbols_exhausted = true;
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for StyledGrapheme { symbol, style } in &mut self.symbols {
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symbols_exhausted = false;
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let symbol_whitespace = symbol.chars().all(&char::is_whitespace) && symbol != NBSP;
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// Ignore characters wider that the total max width.
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if Cast::<u16>::cast(symbol.width()) > self.max_line_width
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// Skip leading whitespace when trim is enabled.
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|| self.trim && symbol_whitespace && symbol != "\n" && current_line_width == 0
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{
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continue;
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}
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// Break on newline and discard it.
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if symbol == "\n" {
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if prev_whitespace {
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current_line_width = width_to_last_word_end;
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self.current_line.truncate(symbols_to_last_word_end);
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}
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break;
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}
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// Mark the previous symbol as word end.
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if symbol_whitespace && !prev_whitespace {
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symbols_to_last_word_end = self.current_line.len();
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width_to_last_word_end = current_line_width;
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}
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self.current_line.push(StyledGrapheme { symbol, style });
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current_line_width += Cast::<u16>::cast(symbol.width());
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if current_line_width > self.max_line_width {
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// If there was no word break in the text, wrap at the end of the line.
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let (truncate_at, truncated_width) = if symbols_to_last_word_end == 0 {
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(self.current_line.len() - 1, self.max_line_width)
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} else {
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(symbols_to_last_word_end, width_to_last_word_end)
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};
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// Push the remainder to the next line but strip leading whitespace:
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{
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let remainder = &self.current_line[truncate_at..];
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if let Some(remainder_nonwhite) =
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remainder.iter().position(|StyledGrapheme { symbol, .. }| {
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!symbol.chars().all(&char::is_whitespace)
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})
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{
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self.next_line
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.extend_from_slice(&remainder[remainder_nonwhite..]);
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}
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}
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self.current_line.truncate(truncate_at);
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current_line_width = truncated_width;
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break;
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}
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prev_whitespace = symbol_whitespace;
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}
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// Even if the iterator is exhausted, pass the previous remainder.
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if symbols_exhausted && self.current_line.is_empty() {
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None
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} else {
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Some((&self.current_line[..], current_line_width))
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}
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}
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}
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/// A state machine that truncates overhanging lines.
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pub struct LineTruncator<'a, 'b> {
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symbols: &'b mut dyn Iterator<Item = StyledGrapheme<'a>>,
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max_line_width: u16,
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current_line: Vec<StyledGrapheme<'a>>,
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/// Record the offet to skip render
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horizontal_offset: u16,
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}
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impl<'a, 'b> LineTruncator<'a, 'b> {
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pub fn new(
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symbols: &'b mut dyn Iterator<Item = StyledGrapheme<'a>>,
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max_line_width: u16,
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) -> LineTruncator<'a, 'b> {
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LineTruncator {
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symbols,
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max_line_width,
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horizontal_offset: 0,
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current_line: vec![],
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}
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}
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pub fn set_horizontal_offset(&mut self, horizontal_offset: u16) {
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self.horizontal_offset = horizontal_offset;
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}
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}
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impl<'a, 'b> LineComposer<'a> for LineTruncator<'a, 'b> {
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fn next_line(&mut self) -> Option<(&[StyledGrapheme<'a>], u16)> {
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if self.max_line_width == 0 {
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return None;
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}
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self.current_line.truncate(0);
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let mut current_line_width = 0;
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let mut skip_rest = false;
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let mut symbols_exhausted = true;
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let mut horizontal_offset = self.horizontal_offset as usize;
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for StyledGrapheme { symbol, style } in &mut self.symbols {
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symbols_exhausted = false;
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// Ignore characters wider that the total max width.
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if Cast::<u16>::cast(symbol.width()) > self.max_line_width {
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continue;
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}
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// Break on newline and discard it.
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if symbol == "\n" {
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break;
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}
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if current_line_width + Cast::<u16>::cast(symbol.width()) > self.max_line_width {
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// Exhaust the remainder of the line.
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skip_rest = true;
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break;
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}
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let symbol = if horizontal_offset == 0 {
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symbol
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} else {
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let w = symbol.width();
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if w > horizontal_offset {
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let t = trim_offset(symbol, horizontal_offset);
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horizontal_offset = 0;
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t
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} else {
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horizontal_offset -= w;
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""
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}
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};
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current_line_width += Cast::<u16>::cast(symbol.width());
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self.current_line.push(StyledGrapheme { symbol, style });
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}
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if skip_rest {
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for StyledGrapheme { symbol, .. } in &mut self.symbols {
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if symbol == "\n" {
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break;
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}
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}
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}
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if symbols_exhausted && self.current_line.is_empty() {
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None
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} else {
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Some((&self.current_line[..], current_line_width))
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}
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}
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}
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/// This function will return a str slice which start at specified offset.
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/// As src is a unicode str, start offset has to be calculated with each character.
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fn trim_offset(src: &str, mut offset: usize) -> &str {
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let mut start = 0;
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for c in UnicodeSegmentation::graphemes(src, true) {
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let w = c.width();
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if w <= offset {
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offset -= w;
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start += c.len();
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} else {
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break;
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}
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}
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&src[start..]
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}
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#[cfg(test)]
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mod test {
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use super::*;
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use unicode_segmentation::UnicodeSegmentation;
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enum Composer {
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WordWrapper { trim: bool },
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LineTruncator,
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}
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fn run_composer(which: Composer, text: &str, text_area_width: u16) -> (Vec<String>, Vec<u16>) {
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let style = Default::default();
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let mut styled =
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UnicodeSegmentation::graphemes(text, true).map(|g| StyledGrapheme { symbol: g, style });
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let mut composer: Box<dyn LineComposer> = match which {
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Composer::WordWrapper { trim } => {
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Box::new(WordWrapper::new(&mut styled, text_area_width, trim))
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}
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Composer::LineTruncator => Box::new(LineTruncator::new(&mut styled, text_area_width)),
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};
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let mut lines = vec![];
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let mut widths = vec![];
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while let Some((styled, width)) = composer.next_line() {
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let line = styled
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.iter()
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.map(|StyledGrapheme { symbol, .. }| *symbol)
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.collect::<String>();
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assert!(width <= text_area_width);
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lines.push(line);
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widths.push(width);
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}
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(lines, widths)
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}
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#[test]
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fn line_composer_one_line() {
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let width = 40;
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for i in 1..width {
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let text = "a".repeat(i);
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let (word_wrapper, _) =
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run_composer(Composer::WordWrapper { trim: true }, &text, width as u16);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, &text, width as u16);
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let expected = vec![text];
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assert_eq!(word_wrapper, expected);
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assert_eq!(line_truncator, expected);
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}
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}
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#[test]
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fn line_composer_short_lines() {
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let width = 20;
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let text =
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"abcdefg\nhijklmno\npabcdefg\nhijklmn\nopabcdefghijk\nlmnopabcd\n\n\nefghijklmno";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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let wrapped: Vec<&str> = text.split('\n').collect();
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assert_eq!(word_wrapper, wrapped);
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assert_eq!(line_truncator, wrapped);
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}
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#[test]
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fn line_composer_long_word() {
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let width = 20;
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let text = "abcdefghijklmnopabcdefghijklmnopabcdefghijklmnopabcdefghijklmno";
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let (word_wrapper, _) =
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run_composer(Composer::WordWrapper { trim: true }, text, width as u16);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width as u16);
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let wrapped = vec![
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&text[..width],
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&text[width..width * 2],
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&text[width * 2..width * 3],
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&text[width * 3..],
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];
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assert_eq!(
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word_wrapper, wrapped,
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"WordWrapper should detect the line cannot be broken on word boundary and \
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break it at line width limit."
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);
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assert_eq!(line_truncator, vec![&text[..width]]);
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}
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#[test]
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fn line_composer_long_sentence() {
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let width = 20;
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let text =
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"abcd efghij klmnopabcd efgh ijklmnopabcdefg hijkl mnopab c d e f g h i j k l m n o";
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let text_multi_space =
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"abcd efghij klmnopabcd efgh ijklmnopabcdefg hijkl mnopab c d e f g h i j k l \
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m n o";
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let (word_wrapper_single_space, _) =
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run_composer(Composer::WordWrapper { trim: true }, text, width as u16);
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let (word_wrapper_multi_space, _) = run_composer(
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Composer::WordWrapper { trim: true },
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text_multi_space,
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width as u16,
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);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width as u16);
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let word_wrapped = vec![
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"abcd efghij",
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"klmnopabcd efgh",
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"ijklmnopabcdefg",
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"hijkl mnopab c d e f",
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"g h i j k l m n o",
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];
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assert_eq!(word_wrapper_single_space, word_wrapped);
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assert_eq!(word_wrapper_multi_space, word_wrapped);
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assert_eq!(line_truncator, vec![&text[..width]]);
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}
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#[test]
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fn line_composer_zero_width() {
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let width = 0;
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let text = "abcd efghij klmnopabcd efgh ijklmnopabcdefg hijkl mnopab ";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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let expected: Vec<&str> = Vec::new();
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assert_eq!(word_wrapper, expected);
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assert_eq!(line_truncator, expected);
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}
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#[test]
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fn line_composer_max_line_width_of_1() {
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let width = 1;
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let text = "abcd efghij klmnopabcd efgh ijklmnopabcdefg hijkl mnopab ";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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let expected: Vec<&str> = UnicodeSegmentation::graphemes(text, true)
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.filter(|g| g.chars().any(|c| !c.is_whitespace()))
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.collect();
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assert_eq!(word_wrapper, expected);
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assert_eq!(line_truncator, vec!["a"]);
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}
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#[test]
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fn line_composer_max_line_width_of_1_double_width_characters() {
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let width = 1;
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let text = "コンピュータ上で文字を扱う場合、典型的には文字\naaaによる通信を行う場合にその\
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両端点では、";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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assert_eq!(word_wrapper, vec!["", "a", "a", "a"]);
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assert_eq!(line_truncator, vec!["", "a"]);
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}
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/// Tests WordWrapper with words some of which exceed line length and some not.
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#[test]
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fn line_composer_word_wrapper_mixed_length() {
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let width = 20;
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let text = "abcd efghij klmnopabcdefghijklmnopabcdefghijkl mnopab cdefghi j klmno";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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assert_eq!(
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word_wrapper,
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vec![
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"abcd efghij",
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"klmnopabcdefghijklmn",
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"opabcdefghijkl",
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"mnopab cdefghi j",
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"klmno",
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]
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)
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}
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#[test]
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fn line_composer_double_width_chars() {
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let width = 20;
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let text = "コンピュータ上で文字を扱う場合、典型的には文字による通信を行う場合にその両端点\
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では、";
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let (word_wrapper, word_wrapper_width) =
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run_composer(Composer::WordWrapper { trim: true }, &text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, &text, width);
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assert_eq!(line_truncator, vec!["コンピュータ上で文字"]);
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let wrapped = vec![
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"コンピュータ上で文字",
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"を扱う場合、典型的に",
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"は文字による通信を行",
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"う場合にその両端点で",
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"は、",
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];
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assert_eq!(word_wrapper, wrapped);
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assert_eq!(word_wrapper_width, vec![width, width, width, width, 4]);
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}
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#[test]
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fn line_composer_leading_whitespace_removal() {
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let width = 20;
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let text = "AAAAAAAAAAAAAAAAAAAA AAA";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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assert_eq!(word_wrapper, vec!["AAAAAAAAAAAAAAAAAAAA", "AAA",]);
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assert_eq!(line_truncator, vec!["AAAAAAAAAAAAAAAAAAAA"]);
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}
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/// Tests truncation of leading whitespace.
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#[test]
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fn line_composer_lots_of_spaces() {
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let width = 20;
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let text = " ";
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let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
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let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
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assert_eq!(word_wrapper, vec![""]);
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assert_eq!(line_truncator, vec![" "]);
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}
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/// Tests an input starting with a letter, folowed by spaces - some of the behaviour is
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/// incidental.
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#[test]
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fn line_composer_char_plus_lots_of_spaces() {
|
||||
let width = 20;
|
||||
let text = "a ";
|
||||
let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
|
||||
let (line_truncator, _) = run_composer(Composer::LineTruncator, text, width);
|
||||
// What's happening below is: the first line gets consumed, trailing spaces discarded,
|
||||
// after 20 of which a word break occurs (probably shouldn't). The second line break
|
||||
// discards all whitespace. The result should probably be vec!["a"] but it doesn't matter
|
||||
// that much.
|
||||
assert_eq!(word_wrapper, vec!["a", ""]);
|
||||
assert_eq!(line_truncator, vec!["a "]);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn line_composer_word_wrapper_double_width_chars_mixed_with_spaces() {
|
||||
let width = 20;
|
||||
// Japanese seems not to use spaces but we should break on spaces anyway... We're using it
|
||||
// to test double-width chars.
|
||||
// You are more than welcome to add word boundary detection based of alterations of
|
||||
// hiragana and katakana...
|
||||
// This happens to also be a test case for mixed width because regular spaces are single width.
|
||||
let text = "コンピュ ータ上で文字を扱う場合、 典型的には文 字による 通信を行 う場合にその両端点では、";
|
||||
let (word_wrapper, word_wrapper_width) =
|
||||
run_composer(Composer::WordWrapper { trim: true }, text, width);
|
||||
assert_eq!(
|
||||
word_wrapper,
|
||||
vec![
|
||||
"コンピュ",
|
||||
"ータ上で文字を扱う場",
|
||||
"合、 典型的には文",
|
||||
"字による 通信を行",
|
||||
"う場合にその両端点で",
|
||||
"は、",
|
||||
]
|
||||
);
|
||||
// Odd-sized lines have a space in them.
|
||||
assert_eq!(word_wrapper_width, vec![8, 20, 17, 17, 20, 4]);
|
||||
}
|
||||
|
||||
/// Ensure words separated by nbsp are wrapped as if they were a single one.
|
||||
#[test]
|
||||
fn line_composer_word_wrapper_nbsp() {
|
||||
let width = 20;
|
||||
let text = "AAAAAAAAAAAAAAA AAAA\u{00a0}AAA";
|
||||
let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: true }, text, width);
|
||||
assert_eq!(word_wrapper, vec!["AAAAAAAAAAAAAAA", "AAAA\u{00a0}AAA",]);
|
||||
|
||||
// Ensure that if the character was a regular space, it would be wrapped differently.
|
||||
let text_space = text.replace("\u{00a0}", " ");
|
||||
let (word_wrapper_space, _) =
|
||||
run_composer(Composer::WordWrapper { trim: true }, &text_space, width);
|
||||
assert_eq!(word_wrapper_space, vec!["AAAAAAAAAAAAAAA AAAA", "AAA",]);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn line_composer_word_wrapper_preserve_indentation() {
|
||||
let width = 20;
|
||||
let text = "AAAAAAAAAAAAAAAAAAAA AAA";
|
||||
let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: false }, text, width);
|
||||
assert_eq!(word_wrapper, vec!["AAAAAAAAAAAAAAAAAAAA", " AAA",]);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn line_composer_word_wrapper_preserve_indentation_with_wrap() {
|
||||
let width = 10;
|
||||
let text = "AAA AAA AAAAA AA AAAAAA\n B\n C\n D";
|
||||
let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: false }, text, width);
|
||||
assert_eq!(
|
||||
word_wrapper,
|
||||
vec!["AAA AAA", "AAAAA AA", "AAAAAA", " B", " C", " D"]
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn line_composer_word_wrapper_preserve_indentation_lots_of_whitespace() {
|
||||
let width = 10;
|
||||
let text = " 4 Indent\n must wrap!";
|
||||
let (word_wrapper, _) = run_composer(Composer::WordWrapper { trim: false }, text, width);
|
||||
assert_eq!(
|
||||
word_wrapper,
|
||||
vec![
|
||||
" ",
|
||||
" 4",
|
||||
"Indent",
|
||||
" ",
|
||||
" must",
|
||||
"wrap!"
|
||||
]
|
||||
);
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,182 @@
|
||||
#![allow(dead_code)]
|
||||
|
||||
use easy_cast::Cast;
|
||||
use std::iter;
|
||||
use tui::{
|
||||
buffer::Buffer,
|
||||
layout::{Alignment, Rect},
|
||||
style::Style,
|
||||
text::{StyledGrapheme, Text},
|
||||
widgets::{Block, StatefulWidget, Widget, Wrap},
|
||||
};
|
||||
use unicode_width::UnicodeWidthStr;
|
||||
|
||||
use super::reflow::{LineComposer, LineTruncator, WordWrapper};
|
||||
|
||||
const fn get_line_offset(line_width: u16, text_area_width: u16, alignment: Alignment) -> u16 {
|
||||
match alignment {
|
||||
Alignment::Center => (text_area_width / 2).saturating_sub(line_width / 2),
|
||||
Alignment::Right => text_area_width.saturating_sub(line_width),
|
||||
Alignment::Left => 0,
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(Debug, Clone)]
|
||||
pub struct StatefulParagraph<'a> {
|
||||
/// A block to wrap the widget in
|
||||
block: Option<Block<'a>>,
|
||||
/// Widget style
|
||||
style: Style,
|
||||
/// How to wrap the text
|
||||
wrap: Option<Wrap>,
|
||||
/// The text to display
|
||||
text: Text<'a>,
|
||||
/// Alignment of the text
|
||||
alignment: Alignment,
|
||||
}
|
||||
|
||||
#[derive(Debug, Default, Clone, Copy)]
|
||||
pub struct ScrollPos {
|
||||
pub x: u16,
|
||||
pub y: u16,
|
||||
}
|
||||
|
||||
impl ScrollPos {
|
||||
pub const fn new(x: u16, y: u16) -> Self {
|
||||
Self { x, y }
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(Debug, Copy, Clone, Default)]
|
||||
pub struct ParagraphState {
|
||||
/// Scroll
|
||||
scroll: ScrollPos,
|
||||
/// after all wrapping this is the amount of lines
|
||||
lines: u16,
|
||||
/// last visible height
|
||||
height: u16,
|
||||
}
|
||||
|
||||
impl ParagraphState {
|
||||
pub const fn lines(self) -> u16 {
|
||||
self.lines
|
||||
}
|
||||
|
||||
pub const fn height(self) -> u16 {
|
||||
self.height
|
||||
}
|
||||
|
||||
pub const fn scroll(self) -> ScrollPos {
|
||||
self.scroll
|
||||
}
|
||||
|
||||
pub fn set_scroll(&mut self, scroll: ScrollPos) {
|
||||
self.scroll = scroll;
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a> StatefulParagraph<'a> {
|
||||
pub fn new<T>(text: T) -> Self
|
||||
where
|
||||
T: Into<Text<'a>>,
|
||||
{
|
||||
Self {
|
||||
block: None,
|
||||
style: Style::default(),
|
||||
wrap: None,
|
||||
text: text.into(),
|
||||
alignment: Alignment::Left,
|
||||
}
|
||||
}
|
||||
|
||||
#[allow(clippy::missing_const_for_fn)]
|
||||
pub fn block(mut self, block: Block<'a>) -> Self {
|
||||
self.block = Some(block);
|
||||
self
|
||||
}
|
||||
|
||||
pub const fn style(mut self, style: Style) -> Self {
|
||||
self.style = style;
|
||||
self
|
||||
}
|
||||
|
||||
pub const fn wrap(mut self, wrap: Wrap) -> Self {
|
||||
self.wrap = Some(wrap);
|
||||
self
|
||||
}
|
||||
|
||||
pub const fn alignment(mut self, alignment: Alignment) -> Self {
|
||||
self.alignment = alignment;
|
||||
self
|
||||
}
|
||||
}
|
||||
|
||||
impl<'a> StatefulWidget for StatefulParagraph<'a> {
|
||||
type State = ParagraphState;
|
||||
|
||||
fn render(mut self, area: Rect, buf: &mut Buffer, state: &mut Self::State) {
|
||||
buf.set_style(area, self.style);
|
||||
let text_area = match self.block.take() {
|
||||
Some(b) => {
|
||||
let inner_area = b.inner(area);
|
||||
b.render(area, buf);
|
||||
inner_area
|
||||
}
|
||||
None => area,
|
||||
};
|
||||
|
||||
if text_area.height < 1 {
|
||||
return;
|
||||
}
|
||||
|
||||
let style = self.style;
|
||||
let mut styled = self.text.lines.iter().flat_map(|spans| {
|
||||
spans
|
||||
.0
|
||||
.iter()
|
||||
.flat_map(|span| span.styled_graphemes(style))
|
||||
// Required given the way composers work but might be refactored out if we change
|
||||
// composers to operate on lines instead of a stream of graphemes.
|
||||
.chain(iter::once(StyledGrapheme {
|
||||
symbol: "\n",
|
||||
style: self.style,
|
||||
}))
|
||||
});
|
||||
|
||||
let mut line_composer: Box<dyn LineComposer> = if let Some(Wrap { trim }) = self.wrap {
|
||||
Box::new(WordWrapper::new(&mut styled, text_area.width, trim))
|
||||
} else {
|
||||
let mut line_composer = Box::new(LineTruncator::new(&mut styled, text_area.width));
|
||||
if let Alignment::Left = self.alignment {
|
||||
line_composer.set_horizontal_offset(state.scroll.x);
|
||||
}
|
||||
line_composer
|
||||
};
|
||||
let mut y = 0;
|
||||
let mut end_reached = false;
|
||||
while let Some((current_line, current_line_width)) = line_composer.next_line() {
|
||||
if !end_reached && y >= state.scroll.y {
|
||||
let mut x = get_line_offset(current_line_width, text_area.width, self.alignment);
|
||||
for StyledGrapheme { symbol, style } in current_line {
|
||||
buf.get_mut(text_area.left() + x, text_area.top() + y - state.scroll.y)
|
||||
.set_symbol(if symbol.is_empty() {
|
||||
// If the symbol is empty, the last char which rendered last time will
|
||||
// leave on the line. It's a quick fix.
|
||||
" "
|
||||
} else {
|
||||
symbol
|
||||
})
|
||||
.set_style(*style);
|
||||
x += Cast::<u16>::cast(symbol.width());
|
||||
}
|
||||
}
|
||||
y += 1;
|
||||
if y >= text_area.height + state.scroll.y {
|
||||
end_reached = true;
|
||||
}
|
||||
}
|
||||
|
||||
state.lines = y;
|
||||
state.height = area.height;
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue