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alacritty/src/renderer/mod.rs
2019-02-04 19:03:25 +00:00

1643 lines
47 KiB
Rust

// 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 std::fs::File;
use std::hash::BuildHasherDefault;
use std::io::{self, Read};
use std::mem::size_of;
use std::path::PathBuf;
use std::ptr;
use std::sync::mpsc;
use std::time::Duration;
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 crate::Rgb;
use crate::config::{self, Config, Delta};
use crate::term::{self, cell, RenderableCell};
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");
static TEXT_SHADER_V_PATH: &'static str = concat!(env!("CARGO_MANIFEST_DIR"), "/res/text.v.glsl");
static RECT_SHADER_F_PATH: &'static str = concat!(env!("CARGO_MANIFEST_DIR"), "/res/rect.f.glsl");
static RECT_SHADER_V_PATH: &'static str = concat!(env!("CARGO_MANIFEST_DIR"), "/res/rect.v.glsl");
// Shader source which is used when live-shader-reload feature is disable
static TEXT_SHADER_F: &'static str =
include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/res/text.f.glsl"));
static TEXT_SHADER_V: &'static str =
include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/res/text.v.glsl"));
static RECT_SHADER_F: &'static str =
include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/res/rect.f.glsl"));
static RECT_SHADER_V: &'static str =
include_str!(concat!(env!("CARGO_MANIFEST_DIR"), "/res/rect.v.glsl"));
/// `LoadGlyph` allows for copying a rasterized glyph into graphics memory
pub trait LoadGlyph {
/// Load the rasterized glyph into GPU memory
fn load_glyph(&mut self, rasterized: &RasterizedGlyph) -> Glyph;
/// Clear any state accumulated from previous loaded glyphs
///
/// This can, for instance, be used to reset the texture Atlas.
fn clear(&mut self);
}
enum Msg {
ShaderReload,
}
#[derive(Debug)]
pub enum Error {
ShaderCreation(ShaderCreationError),
}
impl ::std::error::Error for Error {
fn cause(&self) -> Option<&dyn (::std::error::Error)> {
match *self {
Error::ShaderCreation(ref err) => Some(err),
}
}
fn description(&self) -> &str {
match *self {
Error::ShaderCreation(ref err) => err.description(),
}
}
}
impl ::std::fmt::Display for Error {
fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
match *self {
Error::ShaderCreation(ref err) => {
write!(f, "There was an error initializing the shaders: {}", err)
}
}
}
}
impl From<ShaderCreationError> for Error {
fn from(val: ShaderCreationError) -> Error {
Error::ShaderCreation(val)
}
}
/// Text drawing program
///
/// Uniforms are prefixed with "u", and vertex attributes are prefixed with "a".
#[derive(Debug)]
pub struct TextShaderProgram {
// Program id
id: GLuint,
/// projection scale and offset uniform
u_projection: GLint,
/// Cell dimensions (pixels)
u_cell_dim: GLint,
/// Background pass flag
///
/// Rendering is split into two passes; 1 for backgrounds, and one for text
u_background: GLint,
}
/// Rectangle drawing program
///
/// Uniforms are prefixed with "u"
#[derive(Debug)]
pub struct RectShaderProgram {
// Program id
id: GLuint,
/// Rectangle color
u_color: GLint,
}
#[derive(Copy, Debug, Clone)]
pub struct Glyph {
tex_id: GLuint,
top: f32,
left: f32,
width: f32,
height: f32,
uv_bot: f32,
uv_left: f32,
uv_width: f32,
uv_height: f32,
}
/// Naïve glyph cache
///
/// Currently only keyed by `char`, and thus not possible to hold different
/// representations of the same code point.
pub struct GlyphCache {
/// Cache of buffered glyphs
cache: HashMap<GlyphKey, Glyph, BuildHasherDefault<FnvHasher>>,
/// Rasterizer for loading new glyphs
rasterizer: Rasterizer,
/// regular font
font_key: FontKey,
/// italic font
italic_key: FontKey,
/// bold font
bold_key: FontKey,
/// font size
font_size: font::Size,
/// glyph offset
glyph_offset: Delta<i8>,
metrics: ::font::Metrics,
}
impl GlyphCache {
pub fn new<L>(
mut rasterizer: Rasterizer,
font: &config::Font,
loader: &mut L,
) -> Result<GlyphCache, font::Error>
where
L: LoadGlyph,
{
let (regular, bold, italic) = Self::compute_font_keys(font, &mut rasterizer)?;
// Need to load at least one glyph for the face before calling metrics.
// The glyph requested here ('m' at the time of writing) has no special
// meaning.
rasterizer.get_glyph(GlyphKey { font_key: regular, c: 'm', size: font.size() })?;
let metrics = rasterizer.metrics(regular, font.size())?;
let mut cache = GlyphCache {
cache: HashMap::default(),
rasterizer,
font_size: font.size(),
font_key: regular,
bold_key: bold,
italic_key: italic,
glyph_offset: *font.glyph_offset(),
metrics,
};
cache.load_glyphs_for_font(regular, loader);
cache.load_glyphs_for_font(bold, loader);
cache.load_glyphs_for_font(italic, loader);
Ok(cache)
}
fn load_glyphs_for_font<L: LoadGlyph>(&mut self, font: FontKey, loader: &mut L) {
let size = self.font_size;
for i in RangeInclusive::new(32u8, 128u8) {
self.get(GlyphKey {
font_key: font,
c: i as char,
size,
}, loader);
}
}
/// Computes font keys for (Regular, Bold, Italic)
fn compute_font_keys(
font: &config::Font,
rasterizer: &mut Rasterizer,
) -> Result<(FontKey, FontKey, FontKey), font::Error> {
let size = font.size();
// Load regular font
let regular_desc = Self::make_desc(&font.normal(), font::Slant::Normal, font::Weight::Normal);
let regular = rasterizer.load_font(&regular_desc, size)?;
// helper to load a description if it is not the regular_desc
let mut load_or_regular = |desc: FontDesc| {
if desc == regular_desc {
regular
} else {
rasterizer
.load_font(&desc, size)
.unwrap_or_else(|_| regular)
}
};
// Load bold font
let bold_desc = Self::make_desc(&font.bold(), font::Slant::Normal, font::Weight::Bold);
let bold = load_or_regular(bold_desc);
// Load italic font
let italic_desc = Self::make_desc(&font.italic(), font::Slant::Italic, font::Weight::Normal);
let italic = load_or_regular(italic_desc);
Ok((regular, bold, italic))
}
fn make_desc(
desc: &config::FontDescription,
slant: font::Slant,
weight: font::Weight,
) -> FontDesc {
let style = if let Some(ref spec) = desc.style {
font::Style::Specific(spec.to_owned())
} else {
font::Style::Description { slant, weight }
};
FontDesc::new(desc.family.clone(), style)
}
pub fn font_metrics(&self) -> font::Metrics {
self.rasterizer
.metrics(self.font_key, self.font_size)
.expect("metrics load since font is loaded at glyph cache creation")
}
pub fn get<'a, L>(&'a mut self, glyph_key: GlyphKey, loader: &mut L) -> &'a Glyph
where L: LoadGlyph
{
let glyph_offset = self.glyph_offset;
let rasterizer = &mut self.rasterizer;
let metrics = &self.metrics;
self.cache
.entry(glyph_key)
.or_insert_with(|| {
let mut rasterized = rasterizer.get_glyph(glyph_key)
.unwrap_or_else(|_| Default::default());
rasterized.left += i32::from(glyph_offset.x);
rasterized.top += i32::from(glyph_offset.y);
rasterized.top -= metrics.descent as i32;
loader.load_glyph(&rasterized)
})
}
pub fn update_font_size<L: LoadGlyph>(
&mut self,
font: &config::Font,
size: font::Size,
dpr: f64,
loader: &mut L
) -> Result<(), font::Error> {
// Clear currently cached data in both GL and the registry
loader.clear();
self.cache = HashMap::default();
// Update dpi scaling
self.rasterizer.update_dpr(dpr as f32);
// Recompute font keys
let font = font.to_owned().with_size(size);
let (regular, bold, italic) = Self::compute_font_keys(&font, &mut self.rasterizer)?;
self.rasterizer.get_glyph(GlyphKey { font_key: regular, c: 'm', size: font.size() })?;
let metrics = self.rasterizer.metrics(regular, size)?;
info!("Font size changed to {:?} with DPR of {}", font.size, dpr);
self.font_size = font.size;
self.font_key = regular;
self.bold_key = bold;
self.italic_key = italic;
self.metrics = metrics;
self.load_glyphs_for_font(regular, loader);
self.load_glyphs_for_font(bold, loader);
self.load_glyphs_for_font(italic, loader);
Ok(())
}
}
#[derive(Debug)]
#[repr(C)]
struct InstanceData {
// coords
col: f32,
row: f32,
// glyph offset
left: f32,
top: f32,
// glyph scale
width: f32,
height: f32,
// uv offset
uv_left: f32,
uv_bot: f32,
// uv scale
uv_width: f32,
uv_height: f32,
// color
r: f32,
g: f32,
b: f32,
// background color
bg_r: f32,
bg_g: f32,
bg_b: f32,
bg_a: f32,
}
#[derive(Debug)]
pub struct QuadRenderer {
program: TextShaderProgram,
rect_program: RectShaderProgram,
vao: GLuint,
ebo: GLuint,
vbo_instance: GLuint,
rect_vao: GLuint,
rect_vbo: GLuint,
atlas: Vec<Atlas>,
current_atlas: usize,
active_tex: GLuint,
batch: Batch,
rx: mpsc::Receiver<Msg>,
}
#[derive(Debug)]
pub struct RenderApi<'a> {
active_tex: &'a mut GLuint,
batch: &'a mut Batch,
atlas: &'a mut Vec<Atlas>,
current_atlas: &'a mut usize,
program: &'a mut TextShaderProgram,
config: &'a Config,
}
#[derive(Debug)]
pub struct LoaderApi<'a> {
active_tex: &'a mut GLuint,
atlas: &'a mut Vec<Atlas>,
current_atlas: &'a mut usize,
}
#[derive(Debug)]
pub struct PackedVertex {
x: f32,
y: f32,
}
#[derive(Debug, Default)]
pub struct Batch {
tex: GLuint,
instances: Vec<InstanceData>,
}
impl Batch {
#[inline]
pub fn new() -> Batch {
Batch {
tex: 0,
instances: Vec::with_capacity(BATCH_MAX),
}
}
pub fn add_item(&mut self, cell: &RenderableCell, glyph: &Glyph) {
if self.is_empty() {
self.tex = glyph.tex_id;
}
self.instances.push(InstanceData {
col: cell.column.0 as f32,
row: cell.line.0 as f32,
top: glyph.top,
left: glyph.left,
width: glyph.width,
height: glyph.height,
uv_bot: glyph.uv_bot,
uv_left: glyph.uv_left,
uv_width: glyph.uv_width,
uv_height: glyph.uv_height,
r: f32::from(cell.fg.r),
g: f32::from(cell.fg.g),
b: f32::from(cell.fg.b),
bg_r: f32::from(cell.bg.r),
bg_g: f32::from(cell.bg.g),
bg_b: f32::from(cell.bg.b),
bg_a: cell.bg_alpha,
});
}
#[inline]
pub fn full(&self) -> bool {
self.capacity() == self.len()
}
#[inline]
pub fn len(&self) -> usize {
self.instances.len()
}
#[inline]
pub fn capacity(&self) -> usize {
BATCH_MAX
}
#[inline]
pub fn is_empty(&self) -> bool {
self.len() == 0
}
#[inline]
pub fn size(&self) -> usize {
self.len() * size_of::<InstanceData>()
}
pub fn clear(&mut self) {
self.tex = 0;
self.instances.clear();
}
}
/// Maximum items to be drawn in a batch.
const BATCH_MAX: usize = 0x1_0000;
const ATLAS_SIZE: i32 = 1024;
impl QuadRenderer {
pub fn new(size: PhysicalSize) -> Result<QuadRenderer, Error> {
let program = TextShaderProgram::new(size)?;
let rect_program = RectShaderProgram::new()?;
let mut vao: GLuint = 0;
let mut ebo: GLuint = 0;
let mut vbo_instance: GLuint = 0;
let mut rect_vao: GLuint = 0;
let mut rect_vbo: GLuint = 0;
let mut rect_ebo: GLuint = 0;
unsafe {
gl::Enable(gl::BLEND);
gl::BlendFunc(gl::SRC1_COLOR, gl::ONE_MINUS_SRC1_COLOR);
gl::Enable(gl::MULTISAMPLE);
// Disable depth mask, as the renderer never uses depth tests
gl::DepthMask(gl::FALSE);
gl::GenVertexArrays(1, &mut vao);
gl::GenBuffers(1, &mut ebo);
gl::GenBuffers(1, &mut vbo_instance);
gl::BindVertexArray(vao);
// ---------------------
// Set up element buffer
// ---------------------
let indices: [u32; 6] = [0, 1, 3, 1, 2, 3];
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, ebo);
gl::BufferData(
gl::ELEMENT_ARRAY_BUFFER,
(6 * size_of::<u32>()) as isize,
indices.as_ptr() as *const _,
gl::STATIC_DRAW,
);
// ----------------------------
// Setup vertex instance buffer
// ----------------------------
gl::BindBuffer(gl::ARRAY_BUFFER, vbo_instance);
gl::BufferData(
gl::ARRAY_BUFFER,
(BATCH_MAX * size_of::<InstanceData>()) as isize,
ptr::null(),
gl::STREAM_DRAW,
);
// coords
gl::VertexAttribPointer(
0,
2,
gl::FLOAT,
gl::FALSE,
size_of::<InstanceData>() as i32,
ptr::null(),
);
gl::EnableVertexAttribArray(0);
gl::VertexAttribDivisor(0, 1);
// glyphoffset
gl::VertexAttribPointer(
1,
4,
gl::FLOAT,
gl::FALSE,
size_of::<InstanceData>() as i32,
(2 * size_of::<f32>()) as *const _,
);
gl::EnableVertexAttribArray(1);
gl::VertexAttribDivisor(1, 1);
// uv
gl::VertexAttribPointer(
2,
4,
gl::FLOAT,
gl::FALSE,
size_of::<InstanceData>() as i32,
(6 * size_of::<f32>()) as *const _,
);
gl::EnableVertexAttribArray(2);
gl::VertexAttribDivisor(2, 1);
// color
gl::VertexAttribPointer(
3,
3,
gl::FLOAT,
gl::FALSE,
size_of::<InstanceData>() as i32,
(10 * size_of::<f32>()) as *const _,
);
gl::EnableVertexAttribArray(3);
gl::VertexAttribDivisor(3, 1);
// color
gl::VertexAttribPointer(
4,
4,
gl::FLOAT,
gl::FALSE,
size_of::<InstanceData>() as i32,
(13 * size_of::<f32>()) as *const _,
);
gl::EnableVertexAttribArray(4);
gl::VertexAttribDivisor(4, 1);
// Rectangle setup
gl::GenVertexArrays(1, &mut rect_vao);
gl::GenBuffers(1, &mut rect_vbo);
gl::GenBuffers(1, &mut rect_ebo);
gl::BindVertexArray(rect_vao);
let indices: [i32; 6] = [
0, 1, 3,
1, 2, 3,
];
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, rect_ebo);
gl::BufferData(
gl::ELEMENT_ARRAY_BUFFER,
(size_of::<i32>() * indices.len()) as _,
indices.as_ptr() as *const _,
gl::STATIC_DRAW
);
// Cleanup
gl::BindVertexArray(0);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
}
let (msg_tx, msg_rx) = mpsc::channel();
if cfg!(feature = "live-shader-reload") {
::std::thread::spawn(move || {
let (tx, rx) = ::std::sync::mpsc::channel();
// The Duration argument is a debouncing period.
let mut watcher =
watcher(tx, Duration::from_millis(10)).expect("create file watcher");
watcher
.watch(TEXT_SHADER_F_PATH, RecursiveMode::NonRecursive)
.expect("watch fragment shader");
watcher
.watch(TEXT_SHADER_V_PATH, RecursiveMode::NonRecursive)
.expect("watch vertex shader");
loop {
let event = rx.recv().expect("watcher event");
match event {
DebouncedEvent::Rename(_, _) => continue,
DebouncedEvent::Create(_)
| DebouncedEvent::Write(_)
| DebouncedEvent::Chmod(_) => {
msg_tx.send(Msg::ShaderReload).expect("msg send ok");
}
_ => {}
}
}
});
}
let mut renderer = QuadRenderer {
program,
rect_program,
vao,
ebo,
vbo_instance,
rect_vao,
rect_vbo,
atlas: Vec::new(),
current_atlas: 0,
active_tex: 0,
batch: Batch::new(),
rx: msg_rx,
};
let atlas = Atlas::new(ATLAS_SIZE);
renderer.atlas.push(atlas);
Ok(renderer)
}
// Draw all rectangles simultaneously to prevent excessive program swaps
pub fn draw_rects(
&mut self,
config: &Config,
props: &term::SizeInfo,
visual_bell_intensity: f64,
cell_line_rects: Lines,
) {
// Swap to rectangle rendering program
unsafe {
// Swap program
gl::UseProgram(self.rect_program.id);
// Remove padding from viewport
gl::Viewport(0, 0, props.width as i32, props.height as i32);
// Change blending strategy
gl::BlendFunc(gl::SRC_ALPHA, gl::ONE_MINUS_SRC_ALPHA);
// Setup data and buffers
gl::BindVertexArray(self.rect_vao);
gl::BindBuffer(gl::ARRAY_BUFFER, self.rect_vbo);
// Position
gl::VertexAttribPointer(0, 2, gl::FLOAT, gl::FALSE, (size_of::<f32>() * 2) as _, ptr::null());
gl::EnableVertexAttribArray(0);
}
// Draw visual bell
let color = config.visual_bell().color();
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
gl::BlendFunc(gl::SRC1_COLOR, gl::ONE_MINUS_SRC1_COLOR);
// Reset data and buffers
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindVertexArray(0);
let padding_x = props.padding_x as i32;
let padding_y = props.padding_y as i32;
let width = props.width as i32;
let height = props.height as i32;
gl::Viewport(padding_x, padding_y, width - 2 * padding_x, height - 2 * padding_y);
// Disable program
gl::UseProgram(0);
}
}
pub fn with_api<F, T>(
&mut self,
config: &Config,
props: &term::SizeInfo,
func: F,
) -> T
where
F: FnOnce(RenderApi<'_>) -> T,
{
// Flush message queue
if let Ok(Msg::ShaderReload) = self.rx.try_recv() {
let size = PhysicalSize::new(f64::from(props.width), f64::from(props.height));
self.reload_shaders(size);
}
while let Ok(_) = self.rx.try_recv() {}
unsafe {
gl::UseProgram(self.program.id);
self.program.set_term_uniforms(props);
gl::BindVertexArray(self.vao);
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, self.ebo);
gl::BindBuffer(gl::ARRAY_BUFFER, self.vbo_instance);
gl::ActiveTexture(gl::TEXTURE0);
}
let res = func(RenderApi {
active_tex: &mut self.active_tex,
batch: &mut self.batch,
atlas: &mut self.atlas,
current_atlas: &mut self.current_atlas,
program: &mut self.program,
config,
});
unsafe {
gl::BindBuffer(gl::ELEMENT_ARRAY_BUFFER, 0);
gl::BindBuffer(gl::ARRAY_BUFFER, 0);
gl::BindVertexArray(0);
gl::UseProgram(0);
}
res
}
pub fn with_loader<F, T>(&mut self, func: F) -> T
where
F: FnOnce(LoaderApi<'_>) -> T,
{
unsafe {
gl::ActiveTexture(gl::TEXTURE0);
}
func(LoaderApi {
active_tex: &mut self.active_tex,
atlas: &mut self.atlas,
current_atlas: &mut self.current_atlas,
})
}
pub fn reload_shaders(&mut self, size: PhysicalSize) {
warn!("Reloading shaders...");
let result = (TextShaderProgram::new(size), RectShaderProgram::new());
let (program, rect_program) = match result {
(Ok(program), Ok(rect_program)) => {
info!("... successfully reloaded shaders");
(program, rect_program)
}
(Err(err), _) | (_, Err(err)) => {
error!("{}", err);
return;
}
};
self.active_tex = 0;
self.program = program;
self.rect_program = rect_program;
}
pub fn resize(&mut self, size: PhysicalSize, padding_x: f32, padding_y: f32) {
let (width, height): (u32, u32) = size.into();
// viewport
unsafe {
let width = width as i32;
let height = height as i32;
let padding_x = padding_x as i32;
let padding_y = padding_y as i32;
gl::Viewport(padding_x, padding_y, width - 2 * padding_x, height - 2 * padding_y);
// update projection
gl::UseProgram(self.program.id);
self.program.update_projection(
width as f32,
height as f32,
padding_x as f32,
padding_y as f32,
);
gl::UseProgram(0);
}
}
// Render a rectangle
//
// This requires the rectangle program to be activated
fn render_rect(&mut self, rect: &Rect<f32>, color: Rgb, alpha: f32, size: &term::SizeInfo) {
// Do nothing when alpha is fully transparent
if alpha == 0. {
return;
}
// Calculate rectangle position
let center_x = size.width / 2.;
let center_y = size.height / 2.;
let x = (rect.x - center_x) / center_x;
let y = -(rect.y - center_y) / center_y;
let width = rect.width / center_x;
let height = rect.height / center_y;
unsafe {
// Setup vertices
let vertices: [f32; 8] = [
x + width, y ,
x + width, y - height,
x , y - height,
x , y ,
];
// Load vertex data into array buffer
gl::BufferData(
gl::ARRAY_BUFFER,
(size_of::<f32>() * vertices.len()) as _,
vertices.as_ptr() as *const _,
gl::STATIC_DRAW
);
// Color
self.rect_program.set_color(color, alpha);
// Draw the rectangle
gl::DrawElements(gl::TRIANGLES, 6, gl::UNSIGNED_INT, ptr::null());
}
}
}
#[derive(Debug, Copy, Clone)]
pub struct Rect<T> {
x: T,
y: T,
width: T,
height: T,
}
impl<T> Rect<T> {
pub fn new(x: T, y: T, width: T, height: T) -> Self {
Rect { x, y, width, height }
}
}
impl<'a> RenderApi<'a> {
pub fn clear(&self, color: Rgb) {
let alpha = self.config.background_opacity().get();
unsafe {
gl::ClearColor(
(f32::from(color.r) / 255.0).min(1.0) * alpha,
(f32::from(color.g) / 255.0).min(1.0) * alpha,
(f32::from(color.b) / 255.0).min(1.0) * alpha,
alpha,
);
gl::Clear(gl::COLOR_BUFFER_BIT);
}
}
fn render_batch(&mut self) {
unsafe {
gl::BufferSubData(
gl::ARRAY_BUFFER,
0,
self.batch.size() as isize,
self.batch.instances.as_ptr() as *const _,
);
}
// Bind texture if necessary
if *self.active_tex != self.batch.tex {
unsafe {
gl::BindTexture(gl::TEXTURE_2D, self.batch.tex);
}
*self.active_tex = self.batch.tex;
}
unsafe {
self.program.set_background_pass(true);
gl::DrawElementsInstanced(
gl::TRIANGLES,
6,
gl::UNSIGNED_INT,
ptr::null(),
self.batch.len() as GLsizei,
);
self.program.set_background_pass(false);
gl::DrawElementsInstanced(
gl::TRIANGLES,
6,
gl::UNSIGNED_INT,
ptr::null(),
self.batch.len() as GLsizei,
);
}
self.batch.clear();
}
/// Render a string in a variable location. Used for printing the render timer, warnings and
/// errors.
pub fn render_string(
&mut self,
string: &str,
line: Line,
glyph_cache: &mut GlyphCache,
color: Rgb
) {
let col = Column(0);
let cells = string
.chars()
.enumerate()
.map(|(i, c)| RenderableCell {
line,
column: col + i,
chars: {
let mut chars = [' '; cell::MAX_ZEROWIDTH_CHARS + 1];
chars[0] = c;
chars
},
bg: color,
fg: Rgb { r: 0, g: 0, b: 0 },
flags: cell::Flags::empty(),
bg_alpha: 1.0,
})
.collect::<Vec<_>>();
for cell in cells {
self.render_cell(cell, glyph_cache);
}
}
#[inline]
fn add_render_item(&mut self, cell: &RenderableCell, glyph: &Glyph) {
// Flush batch if tex changing
if !self.batch.is_empty() && self.batch.tex != glyph.tex_id {
self.render_batch();
}
self.batch.add_item(cell, glyph);
// Render batch and clear if it's full
if self.batch.full() {
self.render_batch();
}
}
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
};
// 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],
};
// 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);
// 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);
}
}
}
/// Load a glyph into a texture atlas
///
/// If the current atlas is full, a new one will be created.
#[inline]
fn load_glyph(
active_tex: &mut GLuint,
atlas: &mut Vec<Atlas>,
current_atlas: &mut usize,
rasterized: &RasterizedGlyph
) -> Glyph {
// At least one atlas is guaranteed to be in the `self.atlas` list; thus
// the unwrap.
match atlas[*current_atlas].insert(rasterized, active_tex) {
Ok(glyph) => glyph,
Err(AtlasInsertError::Full) => {
*current_atlas += 1;
if *current_atlas == atlas.len() {
let new = Atlas::new(ATLAS_SIZE);
*active_tex = 0; // Atlas::new binds a texture. Ugh this is sloppy.
atlas.push(new);
}
load_glyph(active_tex, atlas, current_atlas, rasterized)
}
Err(AtlasInsertError::GlyphTooLarge) => {
Glyph {
tex_id: atlas[*current_atlas].id,
top: 0.0,
left: 0.0,
width: 0.0,
height: 0.0,
uv_bot: 0.0,
uv_left: 0.0,
uv_width: 0.0,
uv_height: 0.0,
}
}
}
}
#[inline]
fn clear_atlas(atlas: &mut Vec<Atlas>, current_atlas: &mut usize) {
for atlas in atlas.iter_mut() {
atlas.clear();
}
*current_atlas = 0;
}
impl<'a> LoadGlyph for LoaderApi<'a> {
fn load_glyph(&mut self, rasterized: &RasterizedGlyph) -> Glyph {
load_glyph(self.active_tex, self.atlas, self.current_atlas, rasterized)
}
fn clear(&mut self) {
clear_atlas(self.atlas, self.current_atlas)
}
}
impl<'a> LoadGlyph for RenderApi<'a> {
fn load_glyph(&mut self, rasterized: &RasterizedGlyph) -> Glyph {
load_glyph(self.active_tex, self.atlas, self.current_atlas, rasterized)
}
fn clear(&mut self) {
clear_atlas(self.atlas, self.current_atlas)
}
}
impl<'a> Drop for RenderApi<'a> {
fn drop(&mut self) {
if !self.batch.is_empty() {
self.render_batch();
}
}
}
impl TextShaderProgram {
pub fn new(size: PhysicalSize) -> Result<TextShaderProgram, ShaderCreationError> {
let (vertex_src, fragment_src) = if cfg!(feature = "live-shader-reload") {
(None, None)
} else {
(Some(TEXT_SHADER_V), Some(TEXT_SHADER_F))
};
let vertex_shader = create_shader(TEXT_SHADER_V_PATH, gl::VERTEX_SHADER, vertex_src)?;
let fragment_shader = create_shader(TEXT_SHADER_F_PATH, gl::FRAGMENT_SHADER, fragment_src)?;
let program = create_program(vertex_shader, fragment_shader)?;
unsafe {
gl::DeleteShader(fragment_shader);
gl::DeleteShader(vertex_shader);
gl::UseProgram(program);
}
macro_rules! cptr {
($thing:expr) => { $thing.as_ptr() as *const _ }
}
macro_rules! assert_uniform_valid {
($uniform:expr) => {
assert!($uniform != gl::INVALID_VALUE as i32);
assert!($uniform != gl::INVALID_OPERATION as i32);
};
( $( $uniform:expr ),* ) => {
$( assert_uniform_valid!($uniform); )*
};
}
// get uniform locations
let (projection, cell_dim, background) = unsafe {
(
gl::GetUniformLocation(program, cptr!(b"projection\0")),
gl::GetUniformLocation(program, cptr!(b"cellDim\0")),
gl::GetUniformLocation(program, cptr!(b"backgroundPass\0")),
)
};
assert_uniform_valid!(projection, cell_dim, background);
let shader = TextShaderProgram {
id: program,
u_projection: projection,
u_cell_dim: cell_dim,
u_background: background,
};
shader.update_projection(size.width as f32, size.height as f32, 0., 0.);
unsafe { gl::UseProgram(0); }
Ok(shader)
}
fn update_projection(&self, width: f32, height: f32, padding_x: f32, padding_y: f32) {
// Bounds check
if (width as u32) < (2 * padding_x as u32) ||
(height as u32) < (2 * padding_y as u32)
{
return;
}
// Compute scale and offset factors, from pixel to ndc space. Y is inverted
// [0, width - 2 * padding_x] to [-1, 1]
// [height - 2 * padding_y, 0] to [-1, 1]
let scale_x = 2. / (width - 2. * padding_x);
let scale_y = -2. / (height - 2. * padding_y);
let offset_x = -1.;
let offset_y = 1.;
info!("Width: {}, Height: {}", width, height);
unsafe {
gl::Uniform4f(self.u_projection, offset_x, offset_y, scale_x, scale_y);
}
}
fn set_term_uniforms(&self, props: &term::SizeInfo) {
unsafe {
gl::Uniform2f(self.u_cell_dim, props.cell_width, props.cell_height);
}
}
fn set_background_pass(&self, background_pass: bool) {
let value = if background_pass { 1 } else { 0 };
unsafe {
gl::Uniform1i(self.u_background, value);
}
}
}
impl Drop for TextShaderProgram {
fn drop(&mut self) {
unsafe {
gl::DeleteProgram(self.id);
}
}
}
impl RectShaderProgram {
pub fn new() -> Result<Self, ShaderCreationError> {
let (vertex_src, fragment_src) = if cfg!(feature = "live-shader-reload") {
(None, None)
} else {
(Some(RECT_SHADER_V), Some(RECT_SHADER_F))
};
let vertex_shader = create_shader(
RECT_SHADER_V_PATH,
gl::VERTEX_SHADER,
vertex_src
)?;
let fragment_shader = create_shader(
RECT_SHADER_F_PATH,
gl::FRAGMENT_SHADER,
fragment_src
)?;
let program = create_program(vertex_shader, fragment_shader)?;
unsafe {
gl::DeleteShader(fragment_shader);
gl::DeleteShader(vertex_shader);
gl::UseProgram(program);
}
// get uniform locations
let u_color = unsafe {
gl::GetUniformLocation(program, b"color\0".as_ptr() as *const _)
};
let shader = RectShaderProgram {
id: program,
u_color,
};
unsafe { gl::UseProgram(0) }
Ok(shader)
}
fn set_color(&self, color: Rgb, alpha: f32) {
unsafe {
gl::Uniform4f(
self.u_color,
f32::from(color.r) / 255.,
f32::from(color.g) / 255.,
f32::from(color.b) / 255.,
alpha,
);
}
}
}
impl Drop for RectShaderProgram {
fn drop(&mut self) {
unsafe {
gl::DeleteProgram(self.id);
}
}
}
fn create_program(vertex: GLuint, fragment: GLuint) -> Result<GLuint, ShaderCreationError> {
unsafe {
let program = gl::CreateProgram();
gl::AttachShader(program, vertex);
gl::AttachShader(program, fragment);
gl::LinkProgram(program);
let mut success: GLint = 0;
gl::GetProgramiv(program, gl::LINK_STATUS, &mut success);
if success == i32::from(gl::TRUE) {
Ok(program)
} else {
Err(ShaderCreationError::Link(get_program_info_log(program)))
}
}
}
fn create_shader(path: &str, kind: GLenum, source: Option<&'static str>)
-> Result<GLuint, ShaderCreationError>
{
let from_disk;
let source = if let Some(src) = source {
src
} else {
from_disk = read_file(path)?;
&from_disk[..]
};
let len: [GLint; 1] = [source.len() as GLint];
let shader = unsafe {
let shader = gl::CreateShader(kind);
gl::ShaderSource(shader, 1, &(source.as_ptr() as *const _), len.as_ptr());
gl::CompileShader(shader);
shader
};
let mut success: GLint = 0;
unsafe {
gl::GetShaderiv(shader, gl::COMPILE_STATUS, &mut success);
}
if success == GLint::from(gl::TRUE) {
Ok(shader)
} else {
// Read log
let log = get_shader_info_log(shader);
// Cleanup
unsafe { gl::DeleteShader(shader); }
Err(ShaderCreationError::Compile(PathBuf::from(path), log))
}
}
fn get_program_info_log(program: GLuint) -> String {
// Get expected log length
let mut max_length: GLint = 0;
unsafe {
gl::GetProgramiv(program, gl::INFO_LOG_LENGTH, &mut max_length);
}
// Read the info log
let mut actual_length: GLint = 0;
let mut buf: Vec<u8> = Vec::with_capacity(max_length as usize);
unsafe {
gl::GetProgramInfoLog(
program,
max_length,
&mut actual_length,
buf.as_mut_ptr() as *mut _,
);
}
// Build a string
unsafe {
buf.set_len(actual_length as usize);
}
// XXX should we expect opengl to return garbage?
String::from_utf8(buf).unwrap()
}
fn get_shader_info_log(shader: GLuint) -> String {
// Get expected log length
let mut max_length: GLint = 0;
unsafe {
gl::GetShaderiv(shader, gl::INFO_LOG_LENGTH, &mut max_length);
}
// Read the info log
let mut actual_length: GLint = 0;
let mut buf: Vec<u8> = Vec::with_capacity(max_length as usize);
unsafe {
gl::GetShaderInfoLog(
shader,
max_length,
&mut actual_length,
buf.as_mut_ptr() as *mut _,
);
}
// Build a string
unsafe {
buf.set_len(actual_length as usize);
}
// XXX should we expect opengl to return garbage?
String::from_utf8(buf).unwrap()
}
fn read_file(path: &str) -> Result<String, io::Error> {
let mut f = File::open(path)?;
let mut buf = String::new();
f.read_to_string(&mut buf)?;
Ok(buf)
}
#[derive(Debug)]
pub enum ShaderCreationError {
/// Error reading file
Io(io::Error),
/// Error compiling shader
Compile(PathBuf, String),
/// Problem linking
Link(String),
}
impl ::std::error::Error for ShaderCreationError {
fn cause(&self) -> Option<&dyn (::std::error::Error)> {
match *self {
ShaderCreationError::Io(ref err) => Some(err),
_ => None,
}
}
fn description(&self) -> &str {
match *self {
ShaderCreationError::Io(ref err) => err.description(),
ShaderCreationError::Compile(ref _path, ref s) => s.as_str(),
ShaderCreationError::Link(ref s) => s.as_str(),
}
}
}
impl ::std::fmt::Display for ShaderCreationError {
fn fmt(&self, f: &mut ::std::fmt::Formatter<'_>) -> ::std::fmt::Result {
match *self {
ShaderCreationError::Io(ref err) => {
write!(f, "Couldn't read shader: {}", err)
},
ShaderCreationError::Compile(ref path, ref log) => {
write!(f, "Failed compiling shader at {}: {}", path.display(), log)
},
ShaderCreationError::Link(ref log) => {
write!(f, "Failed linking shader: {}", log)
},
}
}
}
impl From<io::Error> for ShaderCreationError {
fn from(val: io::Error) -> ShaderCreationError {
ShaderCreationError::Io(val)
}
}
/// Manages a single texture atlas
///
/// The strategy for filling an atlas looks roughly like this:
///
/// ```ignore
/// (width, height)
/// ┌─────┬─────┬─────┬─────┬─────┐
/// │ 10 │ │ │ │ │ <- Empty spaces; can be filled while
/// │ │ │ │ │ │ glyph_height < height - row_baseline
/// ├⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┤
/// │ 5 │ 6 │ 7 │ 8 │ 9 │
/// │ │ │ │ │ │
/// ├⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┼⎼⎼⎼⎼⎼┴⎼⎼⎼⎼⎼┤ <- Row height is tallest glyph in row; this is
/// │ 1 │ 2 │ 3 │ 4 │ used as the baseline for the following row.
/// │ │ │ │ │ <- Row considered full when next glyph doesn't
/// └─────┴─────┴─────┴───────────┘ fit in the row.
/// (0, 0) x->
/// ```
#[derive(Debug)]
struct Atlas {
/// Texture id for this atlas
id: GLuint,
/// Width of atlas
width: i32,
/// Height of atlas
height: i32,
/// Left-most free pixel in a row.
///
/// This is called the extent because it is the upper bound of used pixels
/// in a row.
row_extent: i32,
/// Baseline for glyphs in the current row
row_baseline: i32,
/// Tallest glyph in current row
///
/// This is used as the advance when end of row is reached
row_tallest: i32,
}
/// Error that can happen when inserting a texture to the Atlas
enum AtlasInsertError {
/// Texture atlas is full
Full,
/// The glyph cannot fit within a single texture
GlyphTooLarge,
}
impl Atlas {
fn new(size: i32) -> Atlas {
let mut id: GLuint = 0;
unsafe {
gl::PixelStorei(gl::UNPACK_ALIGNMENT, 1);
gl::GenTextures(1, &mut id);
gl::BindTexture(gl::TEXTURE_2D, id);
gl::TexImage2D(
gl::TEXTURE_2D,
0,
gl::RGB as i32,
size,
size,
0,
gl::RGB,
gl::UNSIGNED_BYTE,
ptr::null(),
);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_S, gl::CLAMP_TO_EDGE as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_WRAP_T, gl::CLAMP_TO_EDGE as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MIN_FILTER, gl::LINEAR as i32);
gl::TexParameteri(gl::TEXTURE_2D, gl::TEXTURE_MAG_FILTER, gl::LINEAR as i32);
gl::BindTexture(gl::TEXTURE_2D, 0);
}
Atlas {
id,
width: size,
height: size,
row_extent: 0,
row_baseline: 0,
row_tallest: 0,
}
}
pub fn clear(&mut self) {
self.row_extent = 0;
self.row_baseline = 0;
self.row_tallest = 0;
}
/// Insert a RasterizedGlyph into the texture atlas
pub fn insert(
&mut self,
glyph: &RasterizedGlyph,
active_tex: &mut u32
) -> Result<Glyph, AtlasInsertError> {
if glyph.width > self.width || glyph.height > self.height {
return Err(AtlasInsertError::GlyphTooLarge);
}
// If there's not enough room in current row, go onto next one
if !self.room_in_row(glyph) {
self.advance_row()?;
}
// If there's still not room, there's nothing that can be done here.
if !self.room_in_row(glyph) {
return Err(AtlasInsertError::Full);
}
// There appears to be room; load the glyph.
Ok(self.insert_inner(glyph, active_tex))
}
/// Insert the glyph without checking for room
///
/// Internal function for use once atlas has been checked for space. GL
/// errors could still occur at this point if we were checking for them;
/// hence, the Result.
fn insert_inner(&mut self, glyph: &RasterizedGlyph, active_tex: &mut u32) -> Glyph {
let offset_y = self.row_baseline;
let offset_x = self.row_extent;
let height = glyph.height as i32;
let width = glyph.width as i32;
unsafe {
gl::BindTexture(gl::TEXTURE_2D, self.id);
// Load data into OpenGL
gl::TexSubImage2D(
gl::TEXTURE_2D,
0,
offset_x,
offset_y,
width,
height,
gl::RGB,
gl::UNSIGNED_BYTE,
glyph.buf.as_ptr() as *const _,
);
gl::BindTexture(gl::TEXTURE_2D, 0);
*active_tex = 0;
}
// Update Atlas state
self.row_extent = offset_x + width;
if height > self.row_tallest {
self.row_tallest = height;
}
// Generate UV coordinates
let uv_bot = offset_y as f32 / self.height as f32;
let uv_left = offset_x as f32 / self.width as f32;
let uv_height = height as f32 / self.height as f32;
let uv_width = width as f32 / self.width as f32;
Glyph {
tex_id: self.id,
top: glyph.top as f32,
width: width as f32,
height: height as f32,
left: glyph.left as f32,
uv_bot,
uv_left,
uv_width,
uv_height,
}
}
/// Check if there's room in the current row for given glyph
fn room_in_row(&self, raw: &RasterizedGlyph) -> bool {
let next_extent = self.row_extent + raw.width as i32;
let enough_width = next_extent <= self.width;
let enough_height = (raw.height as i32) < (self.height - self.row_baseline);
enough_width && enough_height
}
/// Mark current row as finished and prepare to insert into the next row
fn advance_row(&mut self) -> Result<(), AtlasInsertError> {
let advance_to = self.row_baseline + self.row_tallest;
if self.height - advance_to <= 0 {
return Err(AtlasInsertError::Full);
}
self.row_baseline = advance_to;
self.row_extent = 0;
self.row_tallest = 0;
Ok(())
}
}