Move renderable cell transformation to alacritty

This refactors a large chunk of the alacritty_terminal API to expose all
data necessary for rendering uniformly through the `renderable_content`
call. This also no longer transforms the cells for rendering by a GUI
but instead just reports the content from a terminal emulation
perspective. The transformation into renderable cells is now done inside
the alacritty crate.

Since the terminal itself only ever needs to know about modified color
RGB values, the configuration for colors was moved to the alacritty UI
code.

Author: chrisduerr

Diff for: CHANGELOG.md

@@ -7,6 +7,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## 0.8.0-dev
 
+### Packaging
+
+- Updated shell completions
+
 ### Added
 
 - IME composition preview not appearing on Windows
@@ -15,9 +19,9 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 - Crash due to assertion failure on 32-bit architectures
 
-### Packaging
+### Removed
 
-- Updated shell completions
+- Config field `visual_bell`, you should use `bell` instead
 
 ## 0.7.1
 

Diff for: Cargo.lock

@@ -10,7 +10,7 @@ edition = "2018"
 
 [dependencies.alacritty_terminal]
 path = "../alacritty_terminal"
-version = "0.12.1-dev"
+version = "0.13.0-dev"
 default-features = false
 
 [dependencies.alacritty_config_derive]

Diff for: alacritty/Cargo.toml

@@ -2,8 +2,8 @@ use std::time::Duration;
 
 use alacritty_config_derive::ConfigDeserialize;
 
-use crate::config::Program;
-use crate::term::color::Rgb;
+use alacritty_terminal::config::Program;
+use alacritty_terminal::term::color::Rgb;
 
 #[derive(ConfigDeserialize, Clone, Debug, PartialEq, Eq)]
 pub struct BellConfig {

Diff for: alacritty_terminal/src/config/bell.rs renamed to alacritty/src/config/bell.rs

@@ -2,8 +2,7 @@ use serde::de::Error as SerdeError;
 use serde::{Deserialize, Deserializer};
 
 use alacritty_config_derive::ConfigDeserialize;
-
-use crate::term::color::{CellRgb, Rgb};
+use alacritty_terminal::term::color::{CellRgb, Rgb};
 
 #[derive(ConfigDeserialize, Clone, Debug, Default, PartialEq, Eq)]
 pub struct Colors {

Diff for: alacritty_terminal/src/config/colors.rs renamed to alacritty/src/config/color.rs

@@ -1,5 +1,5 @@
 use std::fmt::{self, Display, Formatter};
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use std::{env, fs, io};
 
 use log::{error, info};
@@ -9,6 +9,8 @@ use serde_yaml::Value;
 
 use alacritty_terminal::config::{Config as TermConfig, LOG_TARGET_CONFIG};
 
+pub mod bell;
+pub mod color;
 pub mod debug;
 pub mod font;
 pub mod monitor;
@@ -123,10 +125,10 @@ pub fn load(options: &Options) -> Config {
 }
 
 /// Attempt to reload the configuration file.
-pub fn reload(config_path: &PathBuf, options: &Options) -> Result<Config> {
+pub fn reload(config_path: &Path, options: &Options) -> Result<Config> {
     // Load config, propagating errors.
     let config_options = options.config_options().clone();
-    let mut config = load_from(&config_path, config_options)?;
+    let mut config = load_from(config_path, config_options)?;
 
     // Override config with CLI options.
     options.override_config(&mut config);
@@ -135,7 +137,7 @@ pub fn reload(config_path: &PathBuf, options: &Options) -> Result<Config> {
 }
 
 /// Load configuration file and log errors.
-fn load_from(path: &PathBuf, cli_config: Value) -> Result<Config> {
+fn load_from(path: &Path, cli_config: Value) -> Result<Config> {
     match read_config(path, cli_config) {
         Ok(config) => Ok(config),
         Err(err) => {
@@ -146,7 +148,7 @@ fn load_from(path: &PathBuf, cli_config: Value) -> Result<Config> {
 }
 
 /// Deserialize configuration file from path.
-fn read_config(path: &PathBuf, cli_config: Value) -> Result<Config> {
+fn read_config(path: &Path, cli_config: Value) -> Result<Config> {
     let mut config_paths = Vec::new();
     let mut config_value = parse_config(&path, &mut config_paths, IMPORT_RECURSION_LIMIT)?;
 
@@ -162,7 +164,7 @@ fn read_config(path: &PathBuf, cli_config: Value) -> Result<Config> {
 
 /// Deserialize all configuration files as generic Value.
 fn parse_config(
-    path: &PathBuf,
+    path: &Path,
     config_paths: &mut Vec<PathBuf>,
     recursion_limit: usize,
 ) -> Result<Value> {

Diff for: alacritty/src/config/mod.rs

@@ -6,7 +6,9 @@ use serde::{Deserialize, Deserializer};
 use alacritty_config_derive::ConfigDeserialize;
 use alacritty_terminal::config::{Percentage, LOG_TARGET_CONFIG};
 
+use crate::config::bell::BellConfig;
 use crate::config::bindings::{self, Binding, KeyBinding, MouseBinding};
+use crate::config::color::Colors;
 use crate::config::debug::Debug;
 use crate::config::font::Font;
 use crate::config::mouse::Mouse;
@@ -31,6 +33,15 @@ pub struct UIConfig {
     /// Live config reload.
     pub live_config_reload: bool,
 
+    /// Bell configuration.
+    pub bell: BellConfig,
+
+    /// RGB values for colors.
+    pub colors: Colors,
+
+    /// Should draw bold text with brighter colors instead of bold font.
+    pub draw_bold_text_with_bright_colors: bool,
+
     /// Path where config was loaded from.
     #[config(skip)]
     pub config_paths: Vec<PathBuf>,
@@ -58,6 +69,9 @@ impl Default for UIConfig {
             key_bindings: Default::default(),
             mouse_bindings: Default::default(),
             background_opacity: Default::default(),
+            bell: Default::default(),
+            colors: Default::default(),
+            draw_bold_text_with_bright_colors: Default::default(),
         }
     }
 }

Diff for: alacritty/src/config/ui_config.rs

@@ -0,0 +1,122 @@
+use std::time::{Duration, Instant};
+
+use crate::config::bell::{BellAnimation, BellConfig};
+
+pub struct VisualBell {
+    /// Visual bell animation.
+    animation: BellAnimation,
+
+    /// Visual bell duration.
+    duration: Duration,
+
+    /// The last time the visual bell rang, if at all.
+    start_time: Option<Instant>,
+}
+
+impl VisualBell {
+    /// Ring the visual bell, and return its intensity.
+    pub fn ring(&mut self) -> f64 {
+        let now = Instant::now();
+        self.start_time = Some(now);
+        self.intensity_at_instant(now)
+    }
+
+    /// Get the currently intensity of the visual bell. The bell's intensity
+    /// ramps down from 1.0 to 0.0 at a rate determined by the bell's duration.
+    pub fn intensity(&self) -> f64 {
+        self.intensity_at_instant(Instant::now())
+    }
+
+    /// Check whether or not the visual bell has completed "ringing".
+    pub fn completed(&mut self) -> bool {
+        match self.start_time {
+            Some(earlier) => {
+                if Instant::now().duration_since(earlier) >= self.duration {
+                    self.start_time = None;
+                }
+                false
+            },
+            None => true,
+        }
+    }
+
+    /// Get the intensity of the visual bell at a particular instant. The bell's
+    /// intensity ramps down from 1.0 to 0.0 at a rate determined by the bell's
+    /// duration.
+    pub fn intensity_at_instant(&self, instant: Instant) -> f64 {
+        // If `duration` is zero, then the VisualBell is disabled; therefore,
+        // its `intensity` is zero.
+        if self.duration == Duration::from_secs(0) {
+            return 0.0;
+        }
+
+        match self.start_time {
+            // Similarly, if `start_time` is `None`, then the VisualBell has not
+            // been "rung"; therefore, its `intensity` is zero.
+            None => 0.0,
+
+            Some(earlier) => {
+                // Finally, if the `instant` at which we wish to compute the
+                // VisualBell's `intensity` occurred before the VisualBell was
+                // "rung", then its `intensity` is also zero.
+                if instant < earlier {
+                    return 0.0;
+                }
+
+                let elapsed = instant.duration_since(earlier);
+                let elapsed_f =
+                    elapsed.as_secs() as f64 + f64::from(elapsed.subsec_nanos()) / 1e9f64;
+                let duration_f = self.duration.as_secs() as f64
+                    + f64::from(self.duration.subsec_nanos()) / 1e9f64;
+
+                // Otherwise, we compute a value `time` from 0.0 to 1.0
+                // inclusive that represents the ratio of `elapsed` time to the
+                // `duration` of the VisualBell.
+                let time = (elapsed_f / duration_f).min(1.0);
+
+                // We use this to compute the inverse `intensity` of the
+                // VisualBell. When `time` is 0.0, `inverse_intensity` is 0.0,
+                // and when `time` is 1.0, `inverse_intensity` is 1.0.
+                let inverse_intensity = match self.animation {
+                    BellAnimation::Ease | BellAnimation::EaseOut => {
+                        cubic_bezier(0.25, 0.1, 0.25, 1.0, time)
+                    },
+                    BellAnimation::EaseOutSine => cubic_bezier(0.39, 0.575, 0.565, 1.0, time),
+                    BellAnimation::EaseOutQuad => cubic_bezier(0.25, 0.46, 0.45, 0.94, time),
+                    BellAnimation::EaseOutCubic => cubic_bezier(0.215, 0.61, 0.355, 1.0, time),
+                    BellAnimation::EaseOutQuart => cubic_bezier(0.165, 0.84, 0.44, 1.0, time),
+                    BellAnimation::EaseOutQuint => cubic_bezier(0.23, 1.0, 0.32, 1.0, time),
+                    BellAnimation::EaseOutExpo => cubic_bezier(0.19, 1.0, 0.22, 1.0, time),
+                    BellAnimation::EaseOutCirc => cubic_bezier(0.075, 0.82, 0.165, 1.0, time),
+                    BellAnimation::Linear => time,
+                };
+
+                // Since we want the `intensity` of the VisualBell to decay over
+                // `time`, we subtract the `inverse_intensity` from 1.0.
+                1.0 - inverse_intensity
+            },
+        }
+    }
+
+    pub fn update_config(&mut self, bell_config: &BellConfig) {
+        self.animation = bell_config.animation;
+        self.duration = bell_config.duration();
+    }
+}
+
+impl From<&BellConfig> for VisualBell {
+    fn from(bell_config: &BellConfig) -> VisualBell {
+        VisualBell {
+            animation: bell_config.animation,
+            duration: bell_config.duration(),
+            start_time: None,
+        }
+    }
+}
+
+fn cubic_bezier(p0: f64, p1: f64, p2: f64, p3: f64, x: f64) -> f64 {
+    (1.0 - x).powi(3) * p0
+        + 3.0 * (1.0 - x).powi(2) * x * p1
+        + 3.0 * (1.0 - x) * x.powi(2) * p2
+        + x.powi(3) * p3
+}