From 2f9b815ebdcee4558284e5e9cef6ef282dc87b08 Mon Sep 17 00:00:00 2001 From: Christian Duerr Date: Sat, 22 Dec 2018 17:16:54 +0000 Subject: [PATCH] Add proper underline and strikeout support This makes use of the new rectangle rendering methods used to display the colored visual bell to add proper underline and strikeout support to Alacritty. --- font/src/darwin/mod.rs | 15 ++++ font/src/ft/mod.rs | 36 ++++++++++ font/src/lib.rs | 4 ++ font/src/rusttype/mod.rs | 21 +++++- src/ansi.rs | 4 +- src/display.rs | 16 +++-- src/renderer/lines.rs | 143 +++++++++++++++++++++++++++++++++++++++ src/renderer/mod.rs | 124 ++++++++++++++++----------------- src/term/cell.rs | 23 ++++--- src/term/mod.rs | 4 +- 10 files changed, 302 insertions(+), 88 deletions(-) create mode 100644 src/renderer/lines.rs diff --git a/font/src/darwin/mod.rs b/font/src/darwin/mod.rs index 7f01f57..ca784ae 100644 --- a/font/src/darwin/mod.rs +++ b/font/src/darwin/mod.rs @@ -430,10 +430,25 @@ impl Font { let leading = self.ct_font.leading() as f64; let line_height = (ascent + descent + leading + 0.5).floor(); + // Strikeout and underline metrics + // CoreText doesn't provide strikeout so we provide our own + let underline_position = + (self.ct_font.underline_position() - descent) + .round() as f32; + let underline_thickness = self.ct_font.underline_thickness() + .round() + .max(1.) as f32; + let strikeout_position = (line_height as f32 / 2. - descent as f32).round(); + let strikeout_thickness = underline_thickness; + Metrics { average_advance, line_height, descent: -(self.ct_font.descent() as f32), + underline_position, + underline_thickness, + strikeout_position, + strikeout_thickness, } } diff --git a/font/src/ft/mod.rs b/font/src/ft/mod.rs index 1d3f64b..03e8bb3 100644 --- a/font/src/ft/mod.rs +++ b/font/src/ft/mod.rs @@ -18,6 +18,7 @@ use std::cmp::min; use std::path::PathBuf; use std::fmt; +use freetype::tt_os2::TrueTypeOS2Table; use freetype::{self, Library}; use libc::c_uint; @@ -86,15 +87,50 @@ impl ::Rasterize for FreeTypeRasterizer { } fn metrics(&self, key: FontKey, _size: Size) -> Result { + let face = self.faces + .get(&key) + .ok_or(Error::FontNotLoaded)?; let full = self.full_metrics(key)?; let height = (full.size_metrics.height / 64) as f64; let descent = (full.size_metrics.descender / 64) as f32; + // Get underline position and thickness in device pixels + let x_scale = full.size_metrics.x_scale as f32 / 65536.0; + let underline_position = + (f32::from(face.ft_face.underline_position()) * x_scale / 64.).round(); + let underline_thickness = + (f32::from(face.ft_face.underline_thickness()) * x_scale / 64.) + .round() + .max(1.); + + // Get strikeout position and thickness in device pixels + let (strikeout_position, strikeout_thickness) = + match TrueTypeOS2Table::from_face(&mut face.ft_face.clone()) + { + Some(os2) => { + let strikeout_position = + (f32::from(os2.y_strikeout_position()) * x_scale / 64.).round(); + let strikeout_thickness = + (f32::from(os2.y_strikeout_size()) * x_scale / 64.).round(); + (strikeout_position, strikeout_thickness) + }, + _ => { + // Fallback if font doesn't provide info about strikeout + trace!("No strikeout data available for font, using fallback."); + let strikeout_position = height as f32 / 2. + descent; + (strikeout_position, underline_thickness) + }, + }; + Ok(Metrics { average_advance: full.cell_width, line_height: height, descent, + underline_position, + underline_thickness, + strikeout_position, + strikeout_thickness, }) } diff --git a/font/src/lib.rs b/font/src/lib.rs index 1db0821..fdba4b8 100644 --- a/font/src/lib.rs +++ b/font/src/lib.rs @@ -336,6 +336,10 @@ pub struct Metrics { pub average_advance: f64, pub line_height: f64, pub descent: f32, + pub underline_position: f32, + pub underline_thickness: f32, + pub strikeout_position: f32, + pub strikeout_thickness: f32, } pub trait Rasterize { diff --git a/font/src/rusttype/mod.rs b/font/src/rusttype/mod.rs index dea5815..2d28a8b 100644 --- a/font/src/rusttype/mod.rs +++ b/font/src/rusttype/mod.rs @@ -33,10 +33,25 @@ impl crate::Rasterize for RustTypeRasterizer { .ok_or(Error::MissingGlyph)? .scaled(scale) .h_metrics(); + + let line_height = f64::from(vmetrics.ascent - vmetrics.descent + vmetrics.line_gap); + let average_advance = f64::from(hmetrics.advance_width); + let descent = vmetrics.descent; + + // Strikeout and underline metrics + // RustType doesn't support these, so we make up our own + let thickness = (descent / 5.).round(); + let underline_position = descent / 2. + thickness / 2.; + let strikeout_position = (line_height as f32 / 2. - descent).round(); + Ok(Metrics { - descent: vmetrics.descent, - average_advance: f64::from(hmetrics.advance_width), - line_height: f64::from(vmetrics.ascent - vmetrics.descent + vmetrics.line_gap), + descent, + average_advance, + line_height, + underline_position, + underline_thickness: thickness, + strikeout_position, + strikeout_thickness: thickness, }) } diff --git a/src/ansi.rs b/src/ansi.rs index db8022e..29b1a45 100644 --- a/src/ansi.rs +++ b/src/ansi.rs @@ -642,7 +642,7 @@ pub enum Attr { Reverse, /// Do not display characters Hidden, - /// Strikethrough text + /// Strikeout text Strike, /// Cancel bold CancelBold, @@ -658,7 +658,7 @@ pub enum Attr { CancelReverse, /// Cancel text hiding CancelHidden, - /// Cancel strike through + /// Cancel strikeout CancelStrike, /// Set indexed foreground color Foreground(Color), diff --git a/src/display.rs b/src/display.rs index 120cd1d..b1575c5 100644 --- a/src/display.rs +++ b/src/display.rs @@ -25,6 +25,7 @@ use crate::config::Config; use font::{self, Rasterize}; use crate::meter::Meter; use crate::renderer::{self, GlyphCache, QuadRenderer}; +use crate::renderer::lines::Lines; use crate::term::{Term, SizeInfo, RenderableCell}; use crate::sync::FairMutex; use crate::window::{self, Window}; @@ -410,19 +411,27 @@ impl Display { { let glyph_cache = &mut self.glyph_cache; + let metrics = glyph_cache.font_metrics(); + let mut cell_line_rects = Lines::new(&metrics, &size_info); // Draw grid { let _sampler = self.meter.sampler(); self.renderer.with_api(config, &size_info, |mut api| { - // Draw the grid - api.render_cells(grid_cells.iter(), glyph_cache); + // Iterate over all non-empty cells in the grid + for cell in grid_cells { + // Update underline/strikeout + cell_line_rects.update_lines(&cell); + + // Draw the cell + api.render_cell(cell, glyph_cache); + } }); } // Draw rectangles - self.renderer.draw_rects(config, &size_info, visual_bell_intensity); + self.renderer.draw_rects(config, &size_info, visual_bell_intensity, cell_line_rects); // Draw render timer if self.render_timer { @@ -490,4 +499,3 @@ impl Display { self.window().set_ime_spot(LogicalPosition::from((nspot_x, nspot_y))); } } - diff --git a/src/renderer/lines.rs b/src/renderer/lines.rs new file mode 100644 index 0000000..556dcb0 --- /dev/null +++ b/src/renderer/lines.rs @@ -0,0 +1,143 @@ +// Copyright 2016 Joe Wilm, The Alacritty Project Contributors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +use std::collections::HashMap; + +use crate::term::{ SizeInfo, RenderableCell}; +use crate::term::cell::Flags; +use crate::renderer::Rect; +use font::Metrics; +use crate::Rgb; + +/// Lines for underline and strikeout. +pub struct Lines<'a> { + inner: Vec<(Rect, Rgb)>, + last_starts: HashMap>, + last_cell: Option, + metrics: &'a Metrics, + size: &'a SizeInfo, +} + +impl<'a> Lines<'a> { + pub fn new(metrics: &'a Metrics, size: &'a SizeInfo) -> Self { + let mut last_starts = HashMap::new(); + last_starts.insert(Flags::UNDERLINE, None); + last_starts.insert(Flags::STRIKEOUT, None); + + Self { + inner: Vec::new(), + last_cell: None, + last_starts, + metrics, + size, + } + } + + /// Convert the stored lines to rectangles for the renderer. + pub fn rects(mut self) -> Vec<(Rect, Rgb)> { + // If there's still a line pending, draw it until the last cell + for (flag, start_cell) in self.last_starts.iter_mut() { + if let Some(start) = start_cell { + self.inner.push( + create_rect( + &start, + &self.last_cell.unwrap(), + *flag, + &self.metrics, + &self.size, + ) + ); + } + } + + self.inner + } + + /// Update the stored lines with the next cell info. + pub fn update_lines(&mut self, cell: &RenderableCell) { + for (flag, start_cell) in self.last_starts.iter_mut() { + let flag = *flag; + *start_cell = match *start_cell { + // Check for end if line is present + Some(ref mut start) => { + // No change in line + if cell.line == start.line && cell.flags.contains(flag) && cell.fg == start.fg { + continue; + } + + self.inner.push( + create_rect( + &start, + &self.last_cell.unwrap(), + flag, + &self.metrics, + &self.size, + ) + ); + + // Start a new line if the flag is present + if cell.flags.contains(flag) { + Some(*cell) + } else { + None + } + } + // Check for new start of line + None => if cell.flags.contains(flag) { + Some(*cell) + } else { + None + }, + }; + } + + self.last_cell = Some(*cell); + } +} + +/// Create a rectangle between two cells. +fn create_rect( + start: &RenderableCell, + end: &RenderableCell, + flag: Flags, + metrics: &Metrics, + size: &SizeInfo, +) -> (Rect, Rgb) { + let start_x = start.column.0 as f32 * size.cell_width; + let end_x = (end.column.0 + 1) as f32 * size.cell_width; + let width = end_x - start_x; + + let (position, height) = match flag { + Flags::UNDERLINE => (metrics.underline_position, metrics.underline_thickness), + Flags::STRIKEOUT => (metrics.strikeout_position, metrics.strikeout_thickness), + _ => unimplemented!("Invalid flag for cell line drawing specified"), + }; + + let cell_bottom = (start.line.0 as f32 + 1.) * size.cell_height; + let baseline = cell_bottom + metrics.descent; + + let mut y = baseline - position - height / 2.; + let max_y = cell_bottom - height; + if y > max_y { + y = max_y; + } + + let rect = Rect::new( + start_x + size.padding_x, + y + size.padding_y, + width, + height, + ); + + (rect, start.fg) +} diff --git a/src/renderer/mod.rs b/src/renderer/mod.rs index c05301c..42a1748 100644 --- a/src/renderer/mod.rs +++ b/src/renderer/mod.rs @@ -23,16 +23,19 @@ use std::time::Duration; use cgmath; use fnv::FnvHasher; +use glutin::dpi::PhysicalSize; use font::{self, FontDesc, FontKey, GlyphKey, Rasterize, RasterizedGlyph, Rasterizer}; +use notify::{watcher, DebouncedEvent, RecursiveMode, Watcher}; + use crate::gl::types::*; use crate::gl; use crate::index::{Column, Line, RangeInclusive}; -use notify::{watcher, DebouncedEvent, RecursiveMode, Watcher}; use crate::Rgb; - use crate::config::{self, Config, Delta}; use crate::term::{self, cell, RenderableCell}; -use glutin::dpi::PhysicalSize; +use crate::renderer::lines::Lines; + +pub mod lines; // Shader paths for live reload static TEXT_SHADER_F_PATH: &'static str = concat!(env!("CARGO_MANIFEST_DIR"), "/res/text.f.glsl"); @@ -699,6 +702,7 @@ impl QuadRenderer { config: &Config, props: &term::SizeInfo, visual_bell_intensity: f64, + cell_line_rects: Lines, ) { // Swap to rectangle rendering program unsafe { @@ -725,6 +729,11 @@ impl QuadRenderer { let rect = Rect::new(0., 0., props.width, props.height); self.render_rect(&rect, color, visual_bell_intensity as f32, props); + // Draw underlines and strikeouts + for cell_line_rect in cell_line_rects.rects() { + self.render_rect(&cell_line_rect.0, cell_line_rect.1, 255., props); + } + // Deactivate rectangle program again unsafe { // Reset blending strategy @@ -902,7 +911,8 @@ impl QuadRenderer { } } -struct Rect { +#[derive(Debug, Copy, Clone)] +pub struct Rect { x: T, y: T, width: T, @@ -910,7 +920,7 @@ struct Rect { } impl Rect { - fn new(x: T, y: T, width: T, height: T) -> Self { + pub fn new(x: T, y: T, width: T, height: T) -> Self { Rect { x, y, width, height } } } @@ -998,7 +1008,9 @@ impl<'a> RenderApi<'a> { }) .collect::>(); - self.render_cells(cells.iter(), glyph_cache); + for cell in cells { + self.render_cell(cell, glyph_cache); + } } #[inline] @@ -1016,74 +1028,52 @@ impl<'a> RenderApi<'a> { } } - pub fn render_cells<'b, I>( - &mut self, - cells: I, - glyph_cache: &mut GlyphCache - ) - where I: Iterator - { - for cell in cells { - // Get font key for cell - // FIXME this is super inefficient. - let font_key = if cell.flags.contains(cell::Flags::BOLD) { - glyph_cache.bold_key - } else if cell.flags.contains(cell::Flags::ITALIC) { - glyph_cache.italic_key - } else { - glyph_cache.font_key - }; + pub fn render_cell(&mut self, cell: RenderableCell, glyph_cache: &mut GlyphCache) { + // Get font key for cell + // FIXME this is super inefficient. + let font_key = if cell.flags.contains(cell::Flags::BOLD) { + glyph_cache.bold_key + } else if cell.flags.contains(cell::Flags::ITALIC) { + glyph_cache.italic_key + } else { + glyph_cache.font_key + }; - // Don't render text of HIDDEN cells - let mut chars = if cell.flags.contains(cell::Flags::HIDDEN) { - [' '; cell::MAX_ZEROWIDTH_CHARS + 1] - } else { - cell.chars - }; + // Don't render text of HIDDEN cells + let mut chars = if cell.flags.contains(cell::Flags::HIDDEN) { + [' '; cell::MAX_ZEROWIDTH_CHARS + 1] + } else { + cell.chars + }; - // Render tabs as spaces in case the font doesn't support it - if chars[0] == '\t' { - chars[0] = ' '; - } + // Render tabs as spaces in case the font doesn't support it + if chars[0] == '\t' { + chars[0] = ' '; + } - let mut glyph_key = GlyphKey { - font_key, - size: glyph_cache.font_size, - c: chars[0], - }; + let mut glyph_key = GlyphKey { + font_key, + size: glyph_cache.font_size, + c: chars[0], + }; - // Add cell to batch - let glyph = glyph_cache.get(glyph_key, self); - self.add_render_item(&cell, glyph); + // Add cell to batch + let glyph = glyph_cache.get(glyph_key, self); + self.add_render_item(&cell, glyph); - // Render zero-width characters - for c in (&chars[1..]).iter().filter(|c| **c != ' ') { - glyph_key.c = *c; - let mut glyph = *glyph_cache.get(glyph_key, self); + // Render zero-width characters + for c in (&chars[1..]).iter().filter(|c| **c != ' ') { + glyph_key.c = *c; + let mut glyph = *glyph_cache.get(glyph_key, self); - // The metrics of zero-width characters are based on rendering - // the character after the current cell, with the anchor at the - // right side of the preceding character. Since we render the - // zero-width characters inside the preceding character, the - // anchor has been moved to the right by one cell. - glyph.left += glyph_cache.metrics.average_advance as f32; + // The metrics of zero-width characters are based on rendering + // the character after the current cell, with the anchor at the + // right side of the preceding character. Since we render the + // zero-width characters inside the preceding character, the + // anchor has been moved to the right by one cell. + glyph.left += glyph_cache.metrics.average_advance as f32; - self.add_render_item(&cell, &glyph); - } - - // FIXME This is a super hacky way to do underlined text. During - // a time crunch to release 0.1, this seemed like a really - // easy, clean hack. - if cell.flags.contains(cell::Flags::UNDERLINE) { - let glyph_key = GlyphKey { - font_key, - size: glyph_cache.font_size, - c: '_', - }; - - let underscore = glyph_cache.get(glyph_key, self); - self.add_render_item(&cell, underscore); - } + self.add_render_item(&cell, &glyph); } } } diff --git a/src/term/cell.rs b/src/term/cell.rs index bd56148..5d3b703 100644 --- a/src/term/cell.rs +++ b/src/term/cell.rs @@ -23,16 +23,17 @@ pub const MAX_ZEROWIDTH_CHARS: usize = 5; bitflags! { #[derive(Serialize, Deserialize)] pub struct Flags: u16 { - const INVERSE = 0b0_0000_0001; - const BOLD = 0b0_0000_0010; - const ITALIC = 0b0_0000_0100; - const UNDERLINE = 0b0_0000_1000; - const WRAPLINE = 0b0_0001_0000; - const WIDE_CHAR = 0b0_0010_0000; - const WIDE_CHAR_SPACER = 0b0_0100_0000; - const DIM = 0b0_1000_0000; - const DIM_BOLD = 0b0_1000_0010; - const HIDDEN = 0b1_0000_0000; + const INVERSE = 0b00_0000_0001; + const BOLD = 0b00_0000_0010; + const ITALIC = 0b00_0000_0100; + const UNDERLINE = 0b00_0000_1000; + const WRAPLINE = 0b00_0001_0000; + const WIDE_CHAR = 0b00_0010_0000; + const WIDE_CHAR_SPACER = 0b00_0100_0000; + const DIM = 0b00_1000_0000; + const DIM_BOLD = 0b00_1000_0010; + const HIDDEN = 0b01_0000_0000; + const STRIKEOUT = 0b10_0000_0000; } } @@ -117,7 +118,7 @@ impl Cell { (self.c == ' ' || self.c == '\t') && self.extra[0] == ' ' && self.bg == Color::Named(NamedColor::Background) - && !self.flags.intersects(Flags::INVERSE | Flags::UNDERLINE) + && !self.flags.intersects(Flags::INVERSE | Flags::UNDERLINE | Flags::STRIKEOUT) } #[inline] diff --git a/src/term/mod.rs b/src/term/mod.rs index fd2fcf8..bb65fba 100644 --- a/src/term/mod.rs +++ b/src/term/mod.rs @@ -419,7 +419,7 @@ impl<'a> RenderableCellsIter<'a> { } } -#[derive(Debug)] +#[derive(Copy, Clone, Debug)] pub struct RenderableCell { /// A _Display_ line (not necessarily an _Active_ line) pub line: Line, @@ -1965,6 +1965,8 @@ impl ansi::Handler for Term { Attr::CancelUnderline => self.cursor.template.flags.remove(cell::Flags::UNDERLINE), Attr::Hidden => self.cursor.template.flags.insert(cell::Flags::HIDDEN), Attr::CancelHidden => self.cursor.template.flags.remove(cell::Flags::HIDDEN), + Attr::Strike => self.cursor.template.flags.insert(cell::Flags::STRIKEOUT), + Attr::CancelStrike => self.cursor.template.flags.remove(cell::Flags::STRIKEOUT), _ => { debug!("Term got unhandled attr: {:?}", attr); }