408 lines
12 KiB
Rust
408 lines
12 KiB
Rust
use crate::{
|
||
mutex::{Mutex, RwLock},
|
||
TextureAtlas,
|
||
};
|
||
use ahash::AHashMap;
|
||
use emath::{vec2, Vec2};
|
||
use std::collections::BTreeSet;
|
||
use std::sync::Arc;
|
||
|
||
// ----------------------------------------------------------------------------
|
||
|
||
#[derive(Clone, Copy, Debug, Default, PartialEq)]
|
||
#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
|
||
pub struct UvRect {
|
||
/// X/Y offset for nice rendering (unit: points).
|
||
pub offset: Vec2,
|
||
|
||
/// Screen size (in points) of this glyph.
|
||
/// Note that the height is different from the font height.
|
||
pub size: Vec2,
|
||
|
||
/// Top left corner UV in texture.
|
||
pub min: [u16; 2],
|
||
|
||
/// Bottom right corner (exclusive).
|
||
pub max: [u16; 2],
|
||
}
|
||
|
||
impl UvRect {
|
||
pub fn is_nothing(&self) -> bool {
|
||
self.min == self.max
|
||
}
|
||
}
|
||
|
||
#[derive(Clone, Copy, Debug)]
|
||
pub struct GlyphInfo {
|
||
pub(crate) id: ab_glyph::GlyphId,
|
||
|
||
/// Unit: points.
|
||
pub advance_width: f32,
|
||
|
||
/// Texture coordinates. None for space.
|
||
pub uv_rect: UvRect,
|
||
}
|
||
|
||
impl Default for GlyphInfo {
|
||
fn default() -> Self {
|
||
Self {
|
||
id: ab_glyph::GlyphId(0),
|
||
advance_width: 0.0,
|
||
uv_rect: Default::default(),
|
||
}
|
||
}
|
||
}
|
||
|
||
// ----------------------------------------------------------------------------
|
||
|
||
/// A specific font with a size.
|
||
/// The interface uses points as the unit for everything.
|
||
pub struct FontImpl {
|
||
name: String,
|
||
ab_glyph_font: ab_glyph::FontArc,
|
||
/// Maximum character height
|
||
scale_in_pixels: u32,
|
||
height_in_points: f32,
|
||
// move each character by this much (hack)
|
||
y_offset: f32,
|
||
pixels_per_point: f32,
|
||
glyph_info_cache: RwLock<AHashMap<char, GlyphInfo>>, // TODO(emilk): standard Mutex
|
||
atlas: Arc<Mutex<TextureAtlas>>,
|
||
}
|
||
|
||
impl FontImpl {
|
||
pub fn new(
|
||
atlas: Arc<Mutex<TextureAtlas>>,
|
||
pixels_per_point: f32,
|
||
name: String,
|
||
ab_glyph_font: ab_glyph::FontArc,
|
||
scale_in_pixels: u32,
|
||
y_offset_points: f32,
|
||
) -> FontImpl {
|
||
assert!(scale_in_pixels > 0);
|
||
assert!(pixels_per_point > 0.0);
|
||
|
||
let height_in_points = scale_in_pixels as f32 / pixels_per_point;
|
||
|
||
// TODO(emilk): use these font metrics?
|
||
// use ab_glyph::ScaleFont as _;
|
||
// let scaled = ab_glyph_font.as_scaled(scale_in_pixels as f32);
|
||
// dbg!(scaled.ascent());
|
||
// dbg!(scaled.descent());
|
||
// dbg!(scaled.line_gap());
|
||
|
||
// Round to closest pixel:
|
||
let y_offset = (y_offset_points * pixels_per_point).round() / pixels_per_point;
|
||
|
||
Self {
|
||
name,
|
||
ab_glyph_font,
|
||
scale_in_pixels,
|
||
height_in_points,
|
||
y_offset,
|
||
pixels_per_point,
|
||
glyph_info_cache: Default::default(),
|
||
atlas,
|
||
}
|
||
}
|
||
|
||
fn ignore_character(&self, chr: char) -> bool {
|
||
if self.name == "emoji-icon-font" {
|
||
// HACK: https://github.com/emilk/egui/issues/1284 https://github.com/jslegers/emoji-icon-font/issues/18
|
||
// Don't show the wrong fullwidth capital letters:
|
||
if 'Ｓ' <= chr && chr <= 'Ｙ' {
|
||
return true;
|
||
}
|
||
}
|
||
|
||
matches!(
|
||
chr,
|
||
// Strip out a religious symbol with secondary nefarious interpretation:
|
||
'\u{534d}' | '\u{5350}' |
|
||
|
||
// Ignore ubuntu-specific stuff in `Ubuntu-Light.ttf`:
|
||
'\u{E0FF}' | '\u{EFFD}' | '\u{F0FF}' | '\u{F200}'
|
||
)
|
||
}
|
||
|
||
/// An un-ordered iterator over all supported characters.
|
||
fn characters(&self) -> impl Iterator<Item = char> + '_ {
|
||
use ab_glyph::Font as _;
|
||
self.ab_glyph_font
|
||
.codepoint_ids()
|
||
.map(|(_, chr)| chr)
|
||
.filter(|&chr| !self.ignore_character(chr))
|
||
}
|
||
|
||
/// `\n` will result in `None`
|
||
fn glyph_info(&self, c: char) -> Option<GlyphInfo> {
|
||
{
|
||
if let Some(glyph_info) = self.glyph_info_cache.read().get(&c) {
|
||
return Some(*glyph_info);
|
||
}
|
||
}
|
||
|
||
if self.ignore_character(c) {
|
||
return None;
|
||
}
|
||
|
||
if c == '\t' {
|
||
if let Some(space) = self.glyph_info(' ') {
|
||
let glyph_info = GlyphInfo {
|
||
advance_width: crate::text::TAB_SIZE as f32 * space.advance_width,
|
||
..GlyphInfo::default()
|
||
};
|
||
self.glyph_info_cache.write().insert(c, glyph_info);
|
||
return Some(glyph_info);
|
||
}
|
||
}
|
||
|
||
// Add new character:
|
||
use ab_glyph::Font as _;
|
||
let glyph_id = self.ab_glyph_font.glyph_id(c);
|
||
|
||
if glyph_id.0 == 0 {
|
||
if invisible_char(c) {
|
||
// hack
|
||
let glyph_info = GlyphInfo::default();
|
||
self.glyph_info_cache.write().insert(c, glyph_info);
|
||
Some(glyph_info)
|
||
} else {
|
||
None // unsupported character
|
||
}
|
||
} else {
|
||
let glyph_info = allocate_glyph(
|
||
&mut self.atlas.lock(),
|
||
&self.ab_glyph_font,
|
||
glyph_id,
|
||
self.scale_in_pixels as f32,
|
||
self.y_offset,
|
||
self.pixels_per_point,
|
||
);
|
||
|
||
self.glyph_info_cache.write().insert(c, glyph_info);
|
||
Some(glyph_info)
|
||
}
|
||
}
|
||
|
||
#[inline]
|
||
pub fn pair_kerning(
|
||
&self,
|
||
last_glyph_id: ab_glyph::GlyphId,
|
||
glyph_id: ab_glyph::GlyphId,
|
||
) -> f32 {
|
||
use ab_glyph::{Font as _, ScaleFont};
|
||
self.ab_glyph_font
|
||
.as_scaled(self.scale_in_pixels as f32)
|
||
.kern(last_glyph_id, glyph_id)
|
||
/ self.pixels_per_point
|
||
}
|
||
|
||
/// Height of one row of text. In points
|
||
#[inline(always)]
|
||
pub fn row_height(&self) -> f32 {
|
||
self.height_in_points
|
||
}
|
||
|
||
#[inline(always)]
|
||
pub fn pixels_per_point(&self) -> f32 {
|
||
self.pixels_per_point
|
||
}
|
||
}
|
||
|
||
type FontIndex = usize;
|
||
|
||
// TODO(emilk): rename?
|
||
/// Wrapper over multiple [`FontImpl`] (e.g. a primary + fallbacks for emojis)
|
||
pub struct Font {
|
||
fonts: Vec<Arc<FontImpl>>,
|
||
/// Lazily calculated.
|
||
characters: Option<BTreeSet<char>>,
|
||
replacement_glyph: (FontIndex, GlyphInfo),
|
||
pixels_per_point: f32,
|
||
row_height: f32,
|
||
glyph_info_cache: AHashMap<char, (FontIndex, GlyphInfo)>,
|
||
}
|
||
|
||
impl Font {
|
||
pub fn new(fonts: Vec<Arc<FontImpl>>) -> Self {
|
||
if fonts.is_empty() {
|
||
return Self {
|
||
fonts,
|
||
characters: None,
|
||
replacement_glyph: Default::default(),
|
||
pixels_per_point: 1.0,
|
||
row_height: 0.0,
|
||
glyph_info_cache: Default::default(),
|
||
};
|
||
}
|
||
|
||
let pixels_per_point = fonts[0].pixels_per_point();
|
||
let row_height = fonts[0].row_height();
|
||
|
||
let mut slf = Self {
|
||
fonts,
|
||
characters: None,
|
||
replacement_glyph: Default::default(),
|
||
pixels_per_point,
|
||
row_height,
|
||
glyph_info_cache: Default::default(),
|
||
};
|
||
|
||
const PRIMARY_REPLACEMENT_CHAR: char = '◻'; // white medium square
|
||
const FALLBACK_REPLACEMENT_CHAR: char = '?'; // fallback for the fallback
|
||
|
||
let replacement_glyph = slf
|
||
.glyph_info_no_cache_or_fallback(PRIMARY_REPLACEMENT_CHAR)
|
||
.or_else(|| slf.glyph_info_no_cache_or_fallback(FALLBACK_REPLACEMENT_CHAR))
|
||
.unwrap_or_else(|| {
|
||
panic!(
|
||
"Failed to find replacement characters {:?} or {:?}",
|
||
PRIMARY_REPLACEMENT_CHAR, FALLBACK_REPLACEMENT_CHAR
|
||
)
|
||
});
|
||
slf.replacement_glyph = replacement_glyph;
|
||
|
||
slf
|
||
}
|
||
|
||
pub fn preload_common_characters(&mut self) {
|
||
// Preload the printable ASCII characters [32, 126] (which excludes control codes):
|
||
const FIRST_ASCII: usize = 32; // 32 == space
|
||
const LAST_ASCII: usize = 126;
|
||
for c in (FIRST_ASCII..=LAST_ASCII).map(|c| c as u8 as char) {
|
||
self.glyph_info(c);
|
||
}
|
||
self.glyph_info('°');
|
||
self.glyph_info(crate::text::PASSWORD_REPLACEMENT_CHAR);
|
||
}
|
||
|
||
/// All supported characters
|
||
pub fn characters(&mut self) -> &BTreeSet<char> {
|
||
self.characters.get_or_insert_with(|| {
|
||
let mut characters = BTreeSet::new();
|
||
for font in &self.fonts {
|
||
characters.extend(font.characters());
|
||
}
|
||
characters
|
||
})
|
||
}
|
||
|
||
#[inline(always)]
|
||
pub fn round_to_pixel(&self, point: f32) -> f32 {
|
||
(point * self.pixels_per_point).round() / self.pixels_per_point
|
||
}
|
||
|
||
/// Height of one row of text. In points
|
||
#[inline(always)]
|
||
pub fn row_height(&self) -> f32 {
|
||
self.row_height
|
||
}
|
||
|
||
pub fn uv_rect(&self, c: char) -> UvRect {
|
||
self.glyph_info_cache
|
||
.get(&c)
|
||
.map(|gi| gi.1.uv_rect)
|
||
.unwrap_or_default()
|
||
}
|
||
|
||
/// Width of this character in points.
|
||
pub fn glyph_width(&mut self, c: char) -> f32 {
|
||
self.glyph_info(c).1.advance_width
|
||
}
|
||
|
||
/// `\n` will (intentionally) show up as the replacement character.
|
||
fn glyph_info(&mut self, c: char) -> (FontIndex, GlyphInfo) {
|
||
if let Some(font_index_glyph_info) = self.glyph_info_cache.get(&c) {
|
||
return *font_index_glyph_info;
|
||
}
|
||
|
||
let font_index_glyph_info = self.glyph_info_no_cache_or_fallback(c);
|
||
let font_index_glyph_info = font_index_glyph_info.unwrap_or(self.replacement_glyph);
|
||
self.glyph_info_cache.insert(c, font_index_glyph_info);
|
||
font_index_glyph_info
|
||
}
|
||
|
||
#[inline]
|
||
pub(crate) fn glyph_info_and_font_impl(&mut self, c: char) -> (Option<&FontImpl>, GlyphInfo) {
|
||
if self.fonts.is_empty() {
|
||
return (None, self.replacement_glyph.1);
|
||
}
|
||
let (font_index, glyph_info) = self.glyph_info(c);
|
||
let font_impl = &self.fonts[font_index];
|
||
(Some(font_impl), glyph_info)
|
||
}
|
||
|
||
fn glyph_info_no_cache_or_fallback(&mut self, c: char) -> Option<(FontIndex, GlyphInfo)> {
|
||
for (font_index, font_impl) in self.fonts.iter().enumerate() {
|
||
if let Some(glyph_info) = font_impl.glyph_info(c) {
|
||
self.glyph_info_cache.insert(c, (font_index, glyph_info));
|
||
return Some((font_index, glyph_info));
|
||
}
|
||
}
|
||
None
|
||
}
|
||
}
|
||
|
||
#[inline]
|
||
fn invisible_char(c: char) -> bool {
|
||
// See https://github.com/emilk/egui/issues/336
|
||
|
||
// From https://www.fileformat.info/info/unicode/category/Cf/list.htm
|
||
('\u{200B}'..='\u{206F}').contains(&c) // TODO(emilk): heed bidi characters
|
||
}
|
||
|
||
fn allocate_glyph(
|
||
atlas: &mut TextureAtlas,
|
||
font: &ab_glyph::FontArc,
|
||
glyph_id: ab_glyph::GlyphId,
|
||
scale_in_pixels: f32,
|
||
y_offset: f32,
|
||
pixels_per_point: f32,
|
||
) -> GlyphInfo {
|
||
assert!(glyph_id.0 != 0);
|
||
use ab_glyph::{Font as _, ScaleFont};
|
||
|
||
let glyph =
|
||
glyph_id.with_scale_and_position(scale_in_pixels, ab_glyph::Point { x: 0.0, y: 0.0 });
|
||
|
||
let uv_rect = font.outline_glyph(glyph).map(|glyph| {
|
||
let bb = glyph.px_bounds();
|
||
let glyph_width = bb.width() as usize;
|
||
let glyph_height = bb.height() as usize;
|
||
if glyph_width == 0 || glyph_height == 0 {
|
||
UvRect::default()
|
||
} else {
|
||
let (glyph_pos, image) = atlas.allocate((glyph_width, glyph_height));
|
||
glyph.draw(|x, y, v| {
|
||
if v > 0.0 {
|
||
let px = glyph_pos.0 + x as usize;
|
||
let py = glyph_pos.1 + y as usize;
|
||
image[(px, py)] = v;
|
||
}
|
||
});
|
||
|
||
let offset_in_pixels = vec2(bb.min.x, scale_in_pixels + bb.min.y);
|
||
let offset = offset_in_pixels / pixels_per_point + y_offset * Vec2::Y;
|
||
UvRect {
|
||
offset,
|
||
size: vec2(glyph_width as f32, glyph_height as f32) / pixels_per_point,
|
||
min: [glyph_pos.0 as u16, glyph_pos.1 as u16],
|
||
max: [
|
||
(glyph_pos.0 + glyph_width) as u16,
|
||
(glyph_pos.1 + glyph_height) as u16,
|
||
],
|
||
}
|
||
}
|
||
});
|
||
let uv_rect = uv_rect.unwrap_or_default();
|
||
|
||
let advance_width_in_points =
|
||
font.as_scaled(scale_in_pixels).h_advance(glyph_id) / pixels_per_point;
|
||
|
||
GlyphInfo {
|
||
id: glyph_id,
|
||
advance_width: advance_width_in_points,
|
||
uv_rect,
|
||
}
|
||
}
|