mirror-ghostty/src/font/shape.zig

102 lines
3.3 KiB
Zig

const std = @import("std");
const options = @import("main.zig").options;
const run = @import("shaper/run.zig");
const feature = @import("shaper/feature.zig");
const configpkg = @import("../config.zig");
const terminal = @import("../terminal/main.zig");
const SharedGrid = @import("main.zig").SharedGrid;
pub const noop = @import("shaper/noop.zig");
pub const harfbuzz = @import("shaper/harfbuzz.zig");
pub const coretext = @import("shaper/coretext.zig");
pub const web_canvas = @import("shaper/web_canvas.zig");
pub const Cache = @import("shaper/Cache.zig");
pub const TextRun = run.TextRun;
pub const RunIterator = run.RunIterator;
pub const Feature = feature.Feature;
pub const FeatureList = feature.FeatureList;
pub const default_features = feature.default_features;
/// Shaper implementation for our compile options.
pub const Shaper = switch (options.backend) {
.freetype,
.fontconfig_freetype,
.coretext_freetype,
.coretext_harfbuzz,
=> harfbuzz.Shaper,
// Note that coretext_freetype cannot use the coretext
// shaper because the coretext shaper requests CoreText
// font faces.
.coretext => coretext.Shaper,
.coretext_noshape => noop.Shaper,
.web_canvas => web_canvas.Shaper,
};
/// A cell is a single single within a terminal that should be rendered
/// for a shaping call. Note all terminal cells may be present; only
/// cells that have a glyph that needs to be rendered.
pub const Cell = struct {
/// The X position of this shaper cell relative to the offset of the
/// run. Because runs are always within a single row, it is expected
/// that the caller can reconstruct the full position of the cell by
/// using the known Y position of the cell and adding the X position
/// to the run offset.
x: u16,
/// An additional offset to apply to the rendering.
x_offset: i16 = 0,
y_offset: i16 = 0,
/// The glyph index for this cell. The font index to use alongside
/// this cell is available in the text run. This glyph index is only
/// valid for a given GroupCache and FontIndex that was used to create
/// the runs.
glyph_index: u32,
};
/// Options for shapers.
pub const Options = struct {
/// Font features to use when shaping.
///
/// Note: eventually, this will move to font.Face probably as we may
/// want to support per-face feature configuration. For now, we only
/// support applying features globally.
features: []const []const u8 = &.{},
};
/// Options for runIterator.
pub const RunOptions = struct {
/// The font state for the terminal screen. This is mutable because
/// cached values may be updated during shaping.
grid: *SharedGrid,
/// The cells for the row to shape.
cells: std.MultiArrayList(terminal.RenderState.Cell).Slice = .empty,
/// The x boundaries of the selection in this row.
selection: ?[2]u16 = null,
/// The cursor position within this row. This is used to break shaping
/// on cursor boundaries. This can be disabled by setting this to
/// null.
cursor_x: ?usize = null,
/// Apply the font break configuration to the run.
pub fn applyBreakConfig(
self: *RunOptions,
config: configpkg.FontShapingBreak,
) void {
if (!config.cursor) self.cursor_x = null;
}
};
test {
_ = Cache;
_ = Shaper;
// Always test noop
_ = noop;
}