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mirror of https://github.com/wez/wezterm.git synced 2024-12-22 21:01:36 +03:00

implement fallback and rendering for color emoji

This commit is contained in:
Wez Furlong 2018-01-15 22:45:25 -08:00
parent 02bab4fcc7
commit 2d5c54a642
2 changed files with 213 additions and 65 deletions

View File

@ -47,6 +47,18 @@ impl Face {
)
}
pub fn set_pixel_sizes(
&mut self,
char_width: u32,
char_height: u32,
) -> Result<(), Error> {
ft_result(
unsafe {
FT_Set_Pixel_Sizes(self.face, char_width , char_height )
},
(),
)
}
pub fn has_codepoint(&self, cp: char) -> bool {
unsafe {
FT_Get_Char_Index(self.face, cp as u64) != 0

View File

@ -17,8 +17,10 @@ use font::ft::hbwrap;
use std::mem;
use std::slice;
#[derive(Copy, Clone, Debug)]
#[derive(Clone, Debug)]
struct GlyphInfo {
text: String,
font_idx: usize,
glyph_pos: u32,
cluster: u32,
x_advance: i32,
@ -29,10 +31,14 @@ struct GlyphInfo {
impl GlyphInfo {
pub fn new(
text: &str,
font_idx: usize,
info: &hbwrap::hb_glyph_info_t,
pos: &hbwrap::hb_glyph_position_t,
) -> GlyphInfo {
GlyphInfo {
text: text.into(),
font_idx,
glyph_pos: info.codepoint,
cluster: info.cluster,
x_advance: pos.x_advance / 64,
@ -45,7 +51,8 @@ impl GlyphInfo {
struct Glyph<'a> {
tex: Texture<'a>,
has_color: bool,
tex: Option<Texture<'a>>,
width: u32,
height: u32,
info: GlyphInfo,
@ -59,39 +66,79 @@ impl<'a> Glyph<'a> {
glyph: &ftwrap::FT_GlyphSlotRec_,
info: &GlyphInfo,
) -> Result<Glyph<'a>, Error> {
// Special case for zero sized bitmaps; we can't
// build a texture with zero dimenions, so we return
// a Glyph with tex=None.
if glyph.bitmap.width == 0 || glyph.bitmap.rows == 0 {
return Ok(Glyph {
has_color: false,
tex: None,
width: glyph.bitmap.width,
height: glyph.bitmap.rows,
info: info.clone(),
bearing_x: glyph.bitmap_left,
bearing_y: glyph.bitmap_top,
});
}
let mode: ftwrap::FT_Pixel_Mode =
unsafe { mem::transmute(glyph.bitmap.pixel_mode as u32) };
// pitch is the number of bytes per source row
let pitch = glyph.bitmap.pitch.abs() as usize;
let height = glyph.bitmap.rows as usize;
let data = unsafe {
slice::from_raw_parts(glyph.bitmap.buffer, height as usize * pitch)
};
match mode {
let (width, mut tex) = match mode {
ftwrap::FT_Pixel_Mode::FT_PIXEL_MODE_LCD => {
let width = (glyph.bitmap.width as usize) / 3;
let height = glyph.bitmap.rows as usize;
let mut tex = texture_creator
let tex = texture_creator
.create_texture_static(
Some(PixelFormatEnum::BGR24),
width as u32,
height as u32,
)
.map_err(failure::err_msg)?;
let data = unsafe {
slice::from_raw_parts(glyph.bitmap.buffer, height * pitch)
};
tex.update(None, data, pitch)?;
Ok(Glyph {
tex,
width: width as u32,
height: height as u32,
info: *info,
bearing_x: glyph.bitmap_left,
bearing_y: glyph.bitmap_top,
})
(width, tex)
}
ftwrap::FT_Pixel_Mode::FT_PIXEL_MODE_BGRA => {
let width = glyph.bitmap.width as usize;
let tex = texture_creator
.create_texture_static(
// Note: the pixelformat is BGRA and we really
// want to use BGRA32 as the PixelFormatEnum
// value (which is endian corrected) but that
// is missing. Instead, we have to go to the
// lower level pixel format value and handle
// the endianness for ourselves
Some(if cfg!(target_endian = "big") {
PixelFormatEnum::BGRA8888
} else {
PixelFormatEnum::ARGB8888
}),
width as u32,
height as u32,
)
.map_err(failure::err_msg)?;
(width, tex)
}
mode @ _ => bail!("unhandled pixel mode: {:?}", mode),
}
};
tex.update(None, data, pitch)?;
Ok(Glyph {
has_color: false,
tex: Some(tex),
width: width as u32,
height: height as u32,
info: info.clone(),
bearing_x: glyph.bitmap_left,
bearing_y: glyph.bitmap_top,
})
}
}
@ -108,14 +155,6 @@ struct FontHolder {
fonts: Vec<FontInfo>,
}
#[derive(Debug)]
struct ShapedCluster {
/// index into FontHolder.fonts
font_idx: usize,
/// holds shaped results
info: Vec<GlyphInfo>,
}
impl Drop for FontHolder {
fn drop(&mut self) {
// Ensure that we drop the fonts before we drop the
@ -133,7 +172,6 @@ impl FontHolder {
let mut pattern = fcwrap::Pattern::new()?;
pattern.family("Operator Mono SSm Lig")?;
pattern.family("Emoji One")?;
pattern.monospace()?;
pattern.config_substitute(fcwrap::MatchKind::Pattern)?;
pattern.default_substitute();
@ -156,8 +194,32 @@ impl FontHolder {
let pat = self.pattern.render_prepare(&pat)?;
let file = pat.get_file()?;
println!("load_next_fallback: file={}", file);
let mut face = self.lib.new_face(file, 0)?;
face.set_char_size(0, self.size * 64, 96, 96)?;
match face.set_char_size(0, self.size * 64, 96, 96) {
Err(err) => {
let sizes = unsafe {
let rec = &(*face.face);
slice::from_raw_parts(
rec.available_sizes,
rec.num_fixed_sizes as usize,
)
};
if sizes.len() == 0 {
return Err(err);
} else {
// Find the best matching size.
// We just take the biggest.
let mut size = 0i16;
for info in sizes.iter() {
size = size.max(info.height);
}
face.set_pixel_sizes(size as u32, size as u32)?;
}
}
Ok(_) => {}
}
let font = hbwrap::Font::new(&face);
self.fonts.push(FontInfo { face, font });
@ -176,7 +238,17 @@ impl FontHolder {
Ok(&mut self.fonts[idx])
}
fn shape(&mut self, s: &str) -> Result<Vec<ShapedCluster>, Error> {
fn shape(
&mut self,
font_idx: usize,
s: &str,
) -> Result<Vec<GlyphInfo>, Error> {
println!(
"shape text for font_idx {} with len {} {}",
font_idx,
s.len(),
s
);
let features = vec![
// kerning
hbwrap::feature_from_string("kern")?,
@ -192,30 +264,97 @@ impl FontHolder {
buf.set_language(hbwrap::language_from_string("en")?);
buf.add_str(s);
let font_idx = 0;
self.shape_with_font(font_idx, &mut buf, &features)?;
let infos = buf.glyph_infos();
let positions = buf.glyph_positions();
let mut cluster = Vec::new();
let mut last_text_pos = None;
let mut first_fallback_pos = None;
// Compute the lengths of the text clusters.
// Ligatures and combining characters mean
// that a single glyph can take the place of
// multiple characters. The 'cluster' member
// of the glyph info is set to the position
// in the input utf8 text, so we make a pass
// over the set of clusters to look for differences
// greater than 1 and backfill the length of
// the corresponding text fragment. We need
// the fragments to properly handle fallback,
// and they're handy to have for debugging
// purposes too.
let mut sizes = Vec::new();
for (i, info) in infos.iter().enumerate() {
let pos = &positions[i];
// TODO: if info.codepoint == 0 here then we should
// rebuild that portion of the string and reshape it
// with the next fallback font
cluster.push(GlyphInfo::new(info, pos));
let pos = info.cluster as usize;
let mut size = 1;
if let Some(last_pos) = last_text_pos {
let diff = pos - last_pos;
if diff > 1 {
sizes[i - 1] = diff;
}
} else if pos != 0 {
size = pos;
}
last_text_pos = Some(pos);
sizes.push(size);
}
if let Some(last_pos) = last_text_pos {
let diff = s.len() - last_pos;
if diff > 1 {
let last = sizes.len() - 1;
sizes[last] = diff;
}
}
println!("sizes: {:?}", sizes);
// Now make a second pass to determine if we need
// to perform fallback to a later font.
// We can determine this by looking at the codepoint.
for (i, info) in infos.iter().enumerate() {
let pos = info.cluster as usize;
if info.codepoint == 0 {
if first_fallback_pos.is_none() {
// Start of a run that needs fallback
first_fallback_pos = Some(pos);
}
} else if let Some(start) = first_fallback_pos {
// End of a fallback run
println!("range: {:?}-{:?} needs fallback", start, pos);
let substr = &s[start..pos];
let mut shape = self.shape(font_idx + 1, substr)?;
cluster.append(&mut shape);
first_fallback_pos = None;
}
if info.codepoint != 0 {
let text = &s[pos..pos + sizes[i]];
println!("glyph from `{}`", text);
cluster.push(
GlyphInfo::new(text, font_idx, info, &positions[i]),
);
}
}
println!("shaped: {:?}", cluster);
// Check to see if we started and didn't finish a
// fallback run.
if let Some(start) = first_fallback_pos {
let substr = &s[start..];
println!(
"at end {:?}-{:?} needs fallback {}",
start,
s.len() - 1,
substr,
);
let mut shape = self.shape(font_idx + 1, substr)?;
cluster.append(&mut shape);
}
Ok(vec![
ShapedCluster {
font_idx,
info: cluster,
},
])
println!("shaped: {:#?}", cluster);
Ok(cluster)
}
fn shape_with_font(
@ -251,24 +390,16 @@ fn glyphs_for_text<'a, T>(
let mut font_holder = FontHolder::new(36)?;
let mut result = Vec::new();
for cluster in font_holder.shape(s)? {
for info in cluster.info.iter() {
if info.glyph_pos == 0 {
println!("skip: no codepoint for this one");
continue;
}
let glyph =
font_holder.load_glyph(cluster.font_idx, info.glyph_pos)?;
if glyph.bitmap.width == 0 || glyph.bitmap.rows == 0 {
println!("skip: bitmap for this has 0 dimensions {:?}", glyph);
continue;
}
let g = Glyph::new(texture_creator, glyph, info)?;
result.push(g);
for info in font_holder.shape(0, s)? {
if info.glyph_pos == 0 {
println!("skip: no codepoint for this one {:?}", info);
continue;
}
let glyph = font_holder.load_glyph(info.font_idx, info.glyph_pos)?;
let g = Glyph::new(texture_creator, glyph, &info)?;
result.push(g);
}
Ok(result)
}
@ -283,7 +414,8 @@ fn run() -> Result<(), Error> {
.build()?;
let mut canvas = window.into_canvas().build()?;
let texture_creator = canvas.texture_creator();
let mut glyphs = glyphs_for_text(&texture_creator, "foo->bar(); ❤")?;
let mut glyphs =
glyphs_for_text(&texture_creator, "!= foo->bar(); ❤ 😍🤢")?;
for event in sdl_context
.event_pump()
@ -305,10 +437,13 @@ fn run() -> Result<(), Error> {
let mut x = 10i32;
let mut y = 100i32;
for g in glyphs.iter_mut() {
g.tex.set_color_mod(0xb3, 0xb3, 0xb3);
canvas
if let &mut Some(ref mut tex) = &mut g.tex {
if !g.has_color {
tex.set_color_mod(0xb3, 0xb3, 0xb3);
}
canvas
.copy(
&g.tex,
&tex,
Some(Rect::new(0, 0, g.width, g.height)),
Some(Rect::new(
x + g.info.x_offset - g.bearing_x,
@ -318,6 +453,7 @@ fn run() -> Result<(), Error> {
)),
)
.map_err(failure::err_msg)?;
}
x += g.info.x_advance;
y += g.info.y_advance;
}