ghostty/src/font/face.zig
2023-07-01 09:55:19 -07:00

80 lines
2.6 KiB
Zig

const builtin = @import("builtin");
const options = @import("main.zig").options;
const freetype = @import("face/freetype.zig");
const coretext = @import("face/coretext.zig");
pub const web_canvas = @import("face/web_canvas.zig");
/// Face implementation for the compile options.
pub const Face = switch (options.backend) {
.freetype,
.fontconfig_freetype,
.coretext_freetype,
=> freetype.Face,
.coretext => coretext.Face,
.web_canvas => web_canvas.Face,
};
/// If a DPI can't be calculated, this DPI is used. This is probably
/// wrong on modern devices so it is highly recommended you get the DPI
/// using whatever platform method you can.
pub const default_dpi = if (builtin.os.tag == .macos) 72 else 96;
/// The desired size for loading a font.
pub const DesiredSize = struct {
// Desired size in points
points: u16,
// The DPI of the screen so we can convert points to pixels.
xdpi: u16 = default_dpi,
ydpi: u16 = default_dpi,
// Converts points to pixels
pub fn pixels(self: DesiredSize) u16 {
// 1 point = 1/72 inch
return (self.points * self.ydpi) / 72;
}
};
/// Metrics associated with the font that are useful for renderers to know.
pub const Metrics = struct {
/// Recommended cell width and height for a monospace grid using this font.
cell_width: f32,
cell_height: f32,
/// For monospace grids, the recommended y-value from the bottom to set
/// the baseline for font rendering. This is chosen so that things such
/// as the bottom of a "g" or "y" do not drop below the cell.
cell_baseline: f32,
/// The position of the underline from the top of the cell and the
/// thickness in pixels.
underline_position: f32,
underline_thickness: f32,
/// The position and thickness of a strikethrough. Same units/style
/// as the underline fields.
strikethrough_position: f32,
strikethrough_thickness: f32,
};
/// Additional options for rendering glyphs.
pub const RenderOptions = struct {
/// The maximum height of the glyph. If this is set, then any glyph
/// larger than this height will be shrunk to this height. The scaling
/// is typically naive, but ultimately up to the rasterizer.
max_height: ?u16 = null,
/// Thicken the glyph. This draws the glyph with a thicker stroke width.
/// This is purely an aesthetic setting.
///
/// This only works with CoreText currently.
thicken: bool = false,
};
pub const Foo = if (options.backend == .coretext) coretext.Face else void;
test {
@import("std").testing.refAllDecls(@This());
}