bootproof/src/graphics/display.rs

57 lines
2.4 KiB
Rust

use crate::graphics::color::Color;
use crate::graphics::font::psf::PSFGlyph;
pub mod gop;
pub trait Display {
fn resolution(&self) -> (usize, usize);
fn width(&self) -> usize { self.resolution().0 }
fn height(&self) -> usize { self.resolution().1 }
unsafe fn set_pixel(&mut self, color: impl Color, x: usize, y: usize);
fn set_pixel_ignore_oob(&mut self, color: impl Color, x: usize, y: usize) {
if x > self.width() || y > self.height() {
return;
}
unsafe {
self.set_pixel(color, x, y);
}
}
fn clear(&mut self, color: impl Color);
unsafe fn draw_glyph(&mut self, color: impl Color, x: usize, y: usize, glyph: PSFGlyph) {
// Glyphs may actually be larger than their nominal bounding box.
// In fact, the Cozette font is like this: the heart symbol is 7 pixels wide,
// despite nominally being a 6x13 font.
// However, despite not being an intended use of the format, that extra pixel
// can still be stored in the padding bits of the glyph (and is!).
// Therefore, we just continue writing those extra bits if they are present.
// Note that there is no similar trick for the height,
// because the height doesn't have padding.
for glyph_x in 0..glyph.width() {
for glyph_y in 0..glyph.height() {
if glyph.get(glyph_x, glyph_y) {
self.set_pixel(color, x + glyph_x as usize, y + glyph_y as usize);
}
}
}
// Sometimes, a font may actually have pixels outside its bounding box!
// For example, in Cozette, a 6x13 font, ♡ is actually 7 pixels wide.
// This data is still stored in the padding bits of the glyph.
// Note that there is no similar trick for height because height doesn't have padding.
// Futhermore, this only works on fonts whose width is not a multiple of eight.
for glyph_x in glyph.width()..num_integer::div_ceil(glyph.width(), 8) * 8 {
for glyph_y in 0..glyph.height() {
if glyph.get(glyph_x, glyph_y) {
// These pixels *nominally* aren't supposed to be there,
// so we only force the pixels inside the bounding box.
self.set_pixel_ignore_oob(color, x + glyph_x as usize, y + glyph_y as usize);
}
}
}
}
}