@@ -143,7 +143,7 @@ impl PlatformTextSystem for MacTextSystem {
fn typographic_bounds(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Bounds<f32>> {
Ok(self.0.read().fonts[font_id.0]
- .typographic_bounds(glyph_id.into())?
+ .typographic_bounds(glyph_id.0)?
.into())
}
@@ -221,11 +221,13 @@ impl MacTextSystemState {
}
fn advance(&self, font_id: FontId, glyph_id: GlyphId) -> Result<Size<f32>> {
- Ok(self.fonts[font_id.0].advance(glyph_id.into())?.into())
+ Ok(self.fonts[font_id.0].advance(glyph_id.0)?.into())
}
fn glyph_for_char(&self, font_id: FontId, ch: char) -> Option<GlyphId> {
- self.fonts[font_id.0].glyph_for_char(ch).map(Into::into)
+ self.fonts[font_id.0]
+ .glyph_for_char(ch)
+ .map(|glyph_id| GlyphId(glyph_id))
}
fn id_for_native_font(&mut self, requested_font: CTFont) -> FontId {
@@ -259,7 +261,7 @@ impl MacTextSystemState {
let scale = Transform2F::from_scale(params.scale_factor);
Ok(font
.raster_bounds(
- params.glyph_id.into(),
+ params.glyph_id.0,
params.font_size.into(),
scale,
HintingOptions::None,
@@ -334,7 +336,7 @@ impl MacTextSystemState {
.native_font()
.clone_with_font_size(f32::from(params.font_size) as CGFloat)
.draw_glyphs(
- &[u32::from(params.glyph_id) as CGGlyph],
+ &[params.glyph_id.0 as CGGlyph],
&[CGPoint::new(
(subpixel_shift.x / params.scale_factor) as CGFloat,
(subpixel_shift.y / params.scale_factor) as CGFloat,
@@ -419,7 +421,7 @@ impl MacTextSystemState {
let glyph_utf16_ix = usize::try_from(*glyph_utf16_ix).unwrap();
ix_converter.advance_to_utf16_ix(glyph_utf16_ix);
glyphs.push(ShapedGlyph {
- id: (*glyph_id).into(),
+ id: GlyphId(*glyph_id as u32),
position: point(position.x as f32, position.y as f32).map(px),
index: ix_converter.utf8_ix,
is_emoji: self.is_emoji(font_id),
@@ -26,15 +26,18 @@ use std::{
sync::Arc,
};
+/// An opaque identifier for a specific font.
#[derive(Hash, PartialEq, Eq, Clone, Copy, Debug)]
#[repr(C)]
pub struct FontId(pub usize);
+/// An opaque identifier for a specific font family.
#[derive(Hash, PartialEq, Eq, Clone, Copy, Debug)]
pub struct FontFamilyId(pub usize);
pub(crate) const SUBPIXEL_VARIANTS: u8 = 4;
+/// The GPUI text layout and rendering sub system.
pub struct TextSystem {
line_layout_cache: Arc<LineLayoutCache>,
platform_text_system: Arc<dyn PlatformTextSystem>,
@@ -65,6 +68,7 @@ impl TextSystem {
}
}
+ /// Get a list of all available font names from the operating system.
pub fn all_font_names(&self) -> Vec<String> {
let mut names: BTreeSet<_> = self
.platform_text_system
@@ -79,10 +83,13 @@ impl TextSystem {
);
names.into_iter().collect()
}
+
+ /// Add a font's data to the text system.
pub fn add_fonts(&self, fonts: &[Arc<Vec<u8>>]) -> Result<()> {
self.platform_text_system.add_fonts(fonts)
}
+ /// Get the FontId for the configure font family and style.
pub fn font_id(&self, font: &Font) -> Result<FontId> {
let font_id = self.font_ids_by_font.read().get(font).copied();
if let Some(font_id) = font_id {
@@ -120,10 +127,14 @@ impl TextSystem {
);
}
+ /// Get the bounding box for the given font and font size.
+ /// A font's bounding box is the smallest rectangle that could enclose all glyphs
+ /// in the font. superimposed over one another.
pub fn bounding_box(&self, font_id: FontId, font_size: Pixels) -> Bounds<Pixels> {
self.read_metrics(font_id, |metrics| metrics.bounding_box(font_size))
}
+ /// Get the typographic bounds for the given character, in the given font and size.
pub fn typographic_bounds(
&self,
font_id: FontId,
@@ -142,6 +153,7 @@ impl TextSystem {
}))
}
+ /// Get the advance width for the given character, in the given font and size.
pub fn advance(&self, font_id: FontId, font_size: Pixels, ch: char) -> Result<Size<Pixels>> {
let glyph_id = self
.platform_text_system
@@ -153,26 +165,35 @@ impl TextSystem {
Ok(result * font_size)
}
+ /// Get the number of font size units per 'em square',
+ /// Per MDN: "an abstract square whose height is the intended distance between
+ /// lines of type in the same type size"
pub fn units_per_em(&self, font_id: FontId) -> u32 {
self.read_metrics(font_id, |metrics| metrics.units_per_em)
}
+ /// Get the height of a captial letter in the given font and size.
pub fn cap_height(&self, font_id: FontId, font_size: Pixels) -> Pixels {
self.read_metrics(font_id, |metrics| metrics.cap_height(font_size))
}
+ /// Get the height of the x character in the given font and size.
pub fn x_height(&self, font_id: FontId, font_size: Pixels) -> Pixels {
self.read_metrics(font_id, |metrics| metrics.x_height(font_size))
}
+ /// Get the recommended distance from the baseline for the given font
pub fn ascent(&self, font_id: FontId, font_size: Pixels) -> Pixels {
self.read_metrics(font_id, |metrics| metrics.ascent(font_size))
}
+ /// Get the recommended distance below the baseline for the given font,
+ /// in single spaced text.
pub fn descent(&self, font_id: FontId, font_size: Pixels) -> Pixels {
self.read_metrics(font_id, |metrics| metrics.descent(font_size))
}
+ /// Get the recommended baseline offset for the given font and line height.
pub fn baseline_offset(
&self,
font_id: FontId,
@@ -199,10 +220,14 @@ impl TextSystem {
}
}
- pub fn with_view<R>(&self, view_id: EntityId, f: impl FnOnce() -> R) -> R {
+ pub(crate) fn with_view<R>(&self, view_id: EntityId, f: impl FnOnce() -> R) -> R {
self.line_layout_cache.with_view(view_id, f)
}
+ /// Layout the given line of text, at the given font_size.
+ /// Subsets of the line can be styled independently with the `runs` parameter.
+ /// Generally, you should prefer to use `TextLayout::shape_line` instead, which
+ /// can be painted directly.
pub fn layout_line(
&self,
text: &str,
@@ -234,6 +259,12 @@ impl TextSystem {
Ok(layout)
}
+ /// Shape the given line, at the given font_size, for painting to the screen.
+ /// Subsets of the line can be styled independently with the `runs` parameter.
+ ///
+ /// Note that this method can only shape a single line of text. It will panic
+ /// if the text contains newlines. If you need to shape multiple lines of text,
+ /// use `TextLayout::shape_text` instead.
pub fn shape_line(
&self,
text: SharedString,
@@ -273,6 +304,9 @@ impl TextSystem {
})
}
+ /// Shape a multi line string of text, at the given font_size, for painting to the screen.
+ /// Subsets of the text can be styled independently with the `runs` parameter.
+ /// If `wrap_width` is provided, the line breaks will be adjusted to fit within the given width.
pub fn shape_text(
&self,
text: SharedString,
@@ -381,6 +415,7 @@ impl TextSystem {
self.line_layout_cache.finish_frame(reused_views)
}
+ /// Returns a handle to a line wrapper, for the given font and font size.
pub fn line_wrapper(self: &Arc<Self>, font: Font, font_size: Pixels) -> LineWrapperHandle {
let lock = &mut self.wrapper_pool.lock();
let font_id = self.resolve_font(&font);
@@ -397,7 +432,8 @@ impl TextSystem {
}
}
- pub fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
+ /// Get the rasterized size and location of a specific, rendered glyph.
+ pub(crate) fn raster_bounds(&self, params: &RenderGlyphParams) -> Result<Bounds<DevicePixels>> {
let raster_bounds = self.raster_bounds.upgradable_read();
if let Some(bounds) = raster_bounds.get(params) {
Ok(*bounds)
@@ -409,7 +445,7 @@ impl TextSystem {
}
}
- pub fn rasterize_glyph(
+ pub(crate) fn rasterize_glyph(
&self,
params: &RenderGlyphParams,
) -> Result<(Size<DevicePixels>, Vec<u8>)> {
@@ -425,6 +461,7 @@ struct FontIdWithSize {
font_size: Pixels,
}
+/// A handle into the text system, which can be used to compute the wrapped layout of text
pub struct LineWrapperHandle {
wrapper: Option<LineWrapper>,
text_system: Arc<TextSystem>,
@@ -517,40 +554,28 @@ impl Display for FontStyle {
}
}
+/// A styled run of text, for use in [`TextLayout`].
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct TextRun {
- // number of utf8 bytes
+ /// A number of utf8 bytes
pub len: usize,
+ /// The font to use for this run.
pub font: Font,
+ /// The color
pub color: Hsla,
+ /// The background color (if any)
pub background_color: Option<Hsla>,
+ /// The underline style (if any)
pub underline: Option<UnderlineStyle>,
}
+/// An identifier for a specific glyph, as returned by [`TextSystem::layout_line`].
#[derive(Copy, Clone, Debug, Eq, PartialEq, Hash)]
#[repr(C)]
-pub struct GlyphId(u32);
-
-impl From<GlyphId> for u32 {
- fn from(value: GlyphId) -> Self {
- value.0
- }
-}
-
-impl From<u16> for GlyphId {
- fn from(num: u16) -> Self {
- GlyphId(num as u32)
- }
-}
-
-impl From<u32> for GlyphId {
- fn from(num: u32) -> Self {
- GlyphId(num)
- }
-}
+pub struct GlyphId(pub(crate) u32);
#[derive(Clone, Debug, PartialEq)]
-pub struct RenderGlyphParams {
+pub(crate) struct RenderGlyphParams {
pub(crate) font_id: FontId,
pub(crate) glyph_id: GlyphId,
pub(crate) font_size: Pixels,
@@ -571,6 +596,7 @@ impl Hash for RenderGlyphParams {
}
}
+/// The parameters for rendering an emoji glyph.
#[derive(Clone, Debug, PartialEq)]
pub struct RenderEmojiParams {
pub(crate) font_id: FontId,
@@ -590,14 +616,23 @@ impl Hash for RenderEmojiParams {
}
}
+/// The configuration details for identifying a specific font.
#[derive(Clone, Debug, Eq, PartialEq, Hash)]
pub struct Font {
+ /// The font family name.
pub family: SharedString,
+
+ /// The font features to use.
pub features: FontFeatures,
+
+ /// The font weight.
pub weight: FontWeight,
+
+ /// The font style.
pub style: FontStyle,
}
+/// Get a [`Font`] for a given name.
pub fn font(family: impl Into<SharedString>) -> Font {
Font {
family: family.into(),
@@ -608,10 +643,17 @@ pub fn font(family: impl Into<SharedString>) -> Font {
}
impl Font {
+ /// Set this Font to be bold
pub fn bold(mut self) -> Self {
self.weight = FontWeight::BOLD;
self
}
+
+ /// Set this Font to be italic
+ pub fn italic(mut self) -> Self {
+ self.style = FontStyle::Italic;
+ self
+ }
}
/// A struct for storing font metrics.
@@ -4,7 +4,9 @@ use schemars::{
};
macro_rules! create_definitions {
- ($($(#[$meta:meta])* ($name:ident, $idx:expr)),* $(,)?) => {
+ ($($(#[$meta:meta])* ($name:ident, $idx:expr), ($comment:tt)),* $(,)?) => {
+
+ /// The font features that can be configured for a given font.
#[derive(Default, Copy, Clone, Eq, PartialEq, Hash)]
pub struct FontFeatures {
enabled: u64,
@@ -13,6 +15,7 @@ macro_rules! create_definitions {
impl FontFeatures {
$(
+ /// $comment
pub fn $name(&self) -> Option<bool> {
if (self.enabled & (1 << $idx)) != 0 {
Some(true)
@@ -125,7 +128,7 @@ macro_rules! create_definitions {
}
create_definitions!(
- (calt, 0),
+ (calt, 0, CALT),
(case, 1),
(cpsp, 2),
(frac, 3),
@@ -1,3 +1,17 @@
+//! The element context is the main interface for interacting with the frame during a paint.
+//!
+//! Elements are hierarchical and with a few exceptions the context accumulates state in a stack
+//! as it processes all of the elements in the frame. The methods that interact with this stack
+//! are generally marked with `with_*`, and take a callback to denote the region of code that
+//! should be executed with that state.
+//!
+//! The other main interface is the `paint_*` family of methods, which push basic drawing commands
+//! to the GPU. Everything in a GPUI app is drawn with these methods.
+//!
+//! There are also several internal methds that GPUI uses, such as [`ElementContext::with_element_state`]
+//! to call the paint and layout methods on elements. These have been included as they're often useful
+//! for taking manual control of the layouting or painting of specialized elements.
+
use std::{
any::{Any, TypeId},
borrow::{Borrow, BorrowMut, Cow},
@@ -153,6 +167,9 @@ pub struct ElementContext<'a> {
}
impl<'a> WindowContext<'a> {
+ /// Convert this window context into an ElementContext in this callback.
+ /// If you need to use this method, you're probably intermixing the imperative
+ /// and declarative APIs, which is not recommended.
pub fn with_element_context<R>(&mut self, f: impl FnOnce(&mut ElementContext) -> R) -> R {
f(&mut ElementContext {
cx: WindowContext::new(self.app, self.window),
@@ -338,6 +355,8 @@ impl<'a> ElementContext<'a> {
self.window.next_frame.next_stacking_order_id = next_stacking_order_id;
}
+ /// Push a text style onto the stack, and call a function with that style active.
+ /// Use [`AppContext::text_style`] to get the current, combined text style.
pub fn with_text_style<F, R>(&mut self, style: Option<TextStyleRefinement>, f: F) -> R
where
F: FnOnce(&mut Self) -> R,
@@ -979,9 +998,8 @@ impl<'a> ElementContext<'a> {
self.window.layout_engine = Some(layout_engine);
}
- /// Obtain the bounds computed for the given LayoutId relative to the window. This method should not
- /// be invoked until the paint phase begins, and will usually be invoked by GPUI itself automatically
- /// in order to pass your element its `Bounds` automatically.
+ /// Obtain the bounds computed for the given LayoutId relative to the window. This method will usually be invoked by
+ /// GPUI itself automatically in order to pass your element its `Bounds` automatically.
pub fn layout_bounds(&mut self, layout_id: LayoutId) -> Bounds<Pixels> {
let mut bounds = self
.window