Max Brunsfeld created
gpui/src/platform.rs | 2
gpui/src/platform/mac/fonts.rs | 150 ++++++++++++++++++++++++++---------
2 files changed, 113 insertions(+), 39 deletions(-)
@@ -136,5 +136,5 @@ pub trait FontSystem: Send + Sync {
font_size: f32,
runs: &[(usize, FontId, ColorU)],
) -> LineLayout;
- fn wrap_line(&self, text: &str, font_size: f32, font_id: FontId) -> Vec<usize>;
+ fn wrap_line(&self, text: &str, font_id: FontId, font_size: f32, width: f32) -> Vec<usize>;
}
@@ -11,7 +11,8 @@ use crate::{
};
use cocoa::appkit::{CGFloat, CGPoint};
use core_foundation::{
- attributed_string::CFMutableAttributedString,
+ array::CFIndex,
+ attributed_string::{CFAttributedStringRef, CFMutableAttributedString},
base::{CFRange, TCFType},
number::CFNumber,
string::CFString,
@@ -22,7 +23,7 @@ use core_graphics::{
use core_text::{line::CTLine, string_attributes::kCTFontAttributeName};
use font_kit::{canvas::RasterizationOptions, hinting::HintingOptions, source::SystemSource};
use parking_lot::RwLock;
-use std::{cell::RefCell, char, convert::TryFrom};
+use std::{cell::RefCell, char, convert::TryFrom, ffi::c_void};
#[allow(non_upper_case_globals)]
const kCGImageAlphaOnly: u32 = 7;
@@ -86,8 +87,8 @@ impl platform::FontSystem for FontSystem {
self.0.read().layout_line(text, font_size, runs)
}
- fn wrap_line(&self, text: &str, font_size: f32, font_id: FontId) -> Vec<usize> {
- self.0.read().wrap_line(text, font_size, font_id)
+ fn wrap_line(&self, text: &str, font_id: FontId, font_size: f32, width: f32) -> Vec<usize> {
+ self.0.read().wrap_line(text, font_id, font_size, width)
}
}
@@ -194,20 +195,9 @@ impl FontSystemState {
) -> LineLayout {
let font_id_attr_name = CFString::from_static_string("zed_font_id");
- let len = text.len();
- let mut utf8_and_utf16_ixs = text.char_indices().chain(Some((len, '\0'))).map({
- let mut utf16_ix = 0;
- move |(utf8_ix, c)| {
- let result = (utf8_ix, utf16_ix);
- utf16_ix += c.len_utf16();
- result
- }
- });
-
// Construct the attributed string, converting UTF8 ranges to UTF16 ranges.
let mut string = CFMutableAttributedString::new();
{
- let mut utf8_and_utf16_ixs = utf8_and_utf16_ixs.clone();
string.replace_str(&CFString::new(text), CFRange::init(0, 0));
let last_run: RefCell<Option<(usize, FontId)>> = Default::default();
@@ -232,19 +222,16 @@ impl FontSystemState {
})
.chain(std::iter::from_fn(|| last_run.borrow_mut().take()));
- let mut utf8_ix = 0;
- let mut utf16_ix = 0;
+ let mut ix_converter = StringIndexConverter::new(text);
for (run_len, font_id) in font_runs {
- let utf8_end = utf8_ix + run_len;
- let utf16_start = utf16_ix;
- while utf8_ix < utf8_end {
- let (next_utf8_ix, next_utf16_ix) = utf8_and_utf16_ixs.next().unwrap();
- utf8_ix = next_utf8_ix;
- utf16_ix = next_utf16_ix;
- }
-
- let cf_range =
- CFRange::init(utf16_start as isize, (utf16_ix - utf16_start) as isize);
+ let utf8_end = ix_converter.utf8_ix + run_len;
+ let utf16_start = ix_converter.utf16_ix;
+ ix_converter.advance_to_utf8_ix(utf8_end);
+
+ let cf_range = CFRange::init(
+ utf16_start as isize,
+ (ix_converter.utf16_ix - utf16_start) as isize,
+ );
let font = &self.fonts[font_id.0];
unsafe {
string.set_attribute(
@@ -264,8 +251,6 @@ impl FontSystemState {
// Retrieve the glyphs from the shaped line, converting UTF16 offsets to UTF8 offsets.
let line = CTLine::new_with_attributed_string(string.as_concrete_TypeRef());
- let mut utf8_ix = 0;
- let mut utf16_ix = 0;
let mut runs = Vec::new();
for run in line.glyph_runs().into_iter() {
let font_id = FontId(
@@ -278,6 +263,7 @@ impl FontSystemState {
.unwrap() as usize,
);
+ let mut ix_converter = StringIndexConverter::new(text);
let mut glyphs = Vec::new();
for ((glyph_id, position), glyph_utf16_ix) in run
.glyphs()
@@ -286,15 +272,11 @@ impl FontSystemState {
.zip(run.string_indices().iter())
{
let glyph_utf16_ix = usize::try_from(*glyph_utf16_ix).unwrap();
- while utf16_ix < glyph_utf16_ix {
- let (next_utf8_ix, next_utf16_ix) = utf8_and_utf16_ixs.next().unwrap();
- utf8_ix = next_utf8_ix;
- utf16_ix = next_utf16_ix;
- }
+ ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
glyphs.push(Glyph {
id: *glyph_id as GlyphId,
position: vec2f(position.x as f32, position.y as f32),
- index: utf8_ix,
+ index: ix_converter.utf8_ix,
});
}
@@ -308,11 +290,11 @@ impl FontSystemState {
descent: typographic_bounds.descent as f32,
runs,
font_size,
- len,
+ len: text.len(),
}
}
- fn wrap_line(&self, text: &str, font_size: f32, font_id: FontId) -> Vec<usize> {
+ fn wrap_line(&self, text: &str, font_id: FontId, font_size: f32, width: f32) -> Vec<usize> {
let mut string = CFMutableAttributedString::new();
string.replace_str(&CFString::new(text), CFRange::init(0, 0));
let cf_range = CFRange::init(0 as isize, text.encode_utf16().count() as isize);
@@ -323,12 +305,79 @@ impl FontSystemState {
kCTFontAttributeName,
&font.native_font().clone_with_font_size(font_size as f64),
);
+
+ let typesetter = CTTypesetterCreateWithAttributedString(string.as_concrete_TypeRef());
+ let mut ix_converter = StringIndexConverter::new(text);
+ let mut break_indices = Vec::new();
+ while ix_converter.utf8_ix < text.len() {
+ let utf16_len = CTTypesetterSuggestLineBreak(
+ typesetter,
+ ix_converter.utf16_ix as isize,
+ width as f64,
+ ) as usize;
+ ix_converter.advance_to_utf16_ix(ix_converter.utf16_ix + utf16_len);
+ break_indices.push(ix_converter.utf8_ix as usize);
+ }
+ break_indices
}
+ }
+}
+
+#[derive(Clone)]
+struct StringIndexConverter<'a> {
+ text: &'a str,
+ utf8_ix: usize,
+ utf16_ix: usize,
+}
+
+impl<'a> StringIndexConverter<'a> {
+ fn new(text: &'a str) -> Self {
+ Self {
+ text,
+ utf8_ix: 0,
+ utf16_ix: 0,
+ }
+ }
+
+ fn advance_to_utf8_ix(&mut self, utf8_target: usize) {
+ for (ix, c) in self.text[self.utf8_ix..].char_indices() {
+ if self.utf8_ix + ix >= utf8_target {
+ self.utf8_ix += ix;
+ return;
+ }
+ self.utf16_ix += c.len_utf16();
+ }
+ self.utf8_ix = self.text.len();
+ }
- Vec::new()
+ fn advance_to_utf16_ix(&mut self, utf16_target: usize) {
+ for (ix, c) in self.text[self.utf8_ix..].char_indices() {
+ if self.utf16_ix >= utf16_target {
+ self.utf8_ix += ix;
+ return;
+ }
+ self.utf16_ix += c.len_utf16();
+ }
+ self.utf8_ix = self.text.len();
}
}
+#[repr(C)]
+pub struct __CFTypesetter(c_void);
+
+pub type CTTypesetterRef = *const __CFTypesetter;
+
+#[link(name = "CoreText", kind = "framework")]
+extern "C" {
+ fn CTTypesetterCreateWithAttributedString(string: CFAttributedStringRef) -> CTTypesetterRef;
+
+ fn CTTypesetterSuggestLineBreak(
+ typesetter: CTTypesetterRef,
+ start_index: CFIndex,
+ width: f64,
+ ) -> CFIndex;
+}
+
#[cfg(test)]
mod tests {
use crate::MutableAppContext;
@@ -429,4 +478,29 @@ mod tests {
writer.write_image_data(&bytes).unwrap();
}
}
+
+ #[test]
+ fn test_layout_line() {
+ let fonts = FontSystem::new();
+ let font_ids = fonts.load_family("Helvetica").unwrap();
+ let font_id = fonts.select_font(&font_ids, &Default::default()).unwrap();
+
+ let line = "one two three four five";
+ let wrap_boundaries = fonts.wrap_line(line, font_id, 16., 64.0);
+ assert_eq!(
+ wrap_boundaries,
+ &["one two ".len(), "one two three ".len(), line.len()]
+ );
+
+ let line = "aaa ααα ✋✋✋ 🎉🎉🎉";
+ let wrap_boundaries = fonts.wrap_line(line, font_id, 16., 64.0);
+ assert_eq!(
+ wrap_boundaries,
+ &[
+ "aaa ααα ".len(),
+ "aaa ααα ✋✋✋ ".len(),
+ "aaa ααα ✋✋✋ 🎉🎉🎉".len(),
+ ]
+ );
+ }
}