bendn's repos / fimg
fast image operations
Diffstat (limited to 'src/drawing/text.rs')
-rw-r--r--src/drawing/text.rs106
1 files changed, 106 insertions, 0 deletions
diff --git a/src/drawing/text.rs b/src/drawing/text.rs
new file mode 100644
index 0000000..00a2d65
--- /dev/null
+++ b/src/drawing/text.rs
@@ -0,0 +1,106 @@
+//! text raster
+
+use crate::{
+ Image, Pack,
+ pixels::{Wam, float},
+};
+use fontdue::{Font, layout::TextStyle};
+use umath::{FF32, generic_float::Constructors};
+
+/// note: `N` may != channels
+pub trait Text<const N: usize> {
+ fn text(&mut self, x: u32, y: u32, size: f32, font: &Font, text: &str, color: [u8; N]);
+}
+
+impl<T: AsMut<[u32]> + AsRef<[u32]>> Text<4> for Image<T, 1> {
+ fn text(&mut self, x: u32, y: u32, size: f32, font: &Font, text: &str, color: [u8; 4]) {
+ let mut lay =
+ fontdue::layout::Layout::new(fontdue::layout::CoordinateSystem::PositiveYDown);
+ lay.append(&[font], &TextStyle::new(text, size, 0));
+ for glpyh in lay.glyphs() {
+ let (metrics, bitmap) = font.rasterize(glpyh.parent, size);
+ for i in 0..metrics.width {
+ for j in 0..metrics.height {
+ let x = x + i as u32 + glpyh.x as u32;
+ if x >= self.width() {
+ continue;
+ }
+ let y = y + j as u32 + glpyh.y as u32;
+ if y >= self.height() {
+ continue;
+ }
+
+ // SAFETY: the rasterizer kinda promises that metrics width and height are in bounds
+ let fill = unsafe { float(*bitmap.get_unchecked(j * metrics.width + i)) };
+ // SAFETY: we clampin
+ let bg: [u8; 4] = unsafe { Pack::unpack(self.pixel(x, y)[0]) };
+ // SAFETY: see above
+ *(&mut unsafe { self.pixel_mut(x, y) }[0]) =
+ // SAFETY: fill is 0..=1
+ Pack::pack(& bg.wam(color, 1.0 - fill, fill));
+ }
+ }
+ }
+ }
+}
+
+impl<const N: usize, T: AsMut<[u8]> + AsRef<[u8]>> Text<N> for Image<T, N> {
+ fn text(&mut self, x: u32, y: u32, size: f32, font: &Font, text: &str, color: [u8; N]) {
+ let mut lay =
+ fontdue::layout::Layout::new(fontdue::layout::CoordinateSystem::PositiveYDown);
+ lay.append(&[font], &TextStyle::new(text, size, 0));
+ for glpyh in lay.glyphs() {
+ let (metrics, bitmap) = font.rasterize(glpyh.parent, size);
+ for i in 0..metrics.width {
+ for j in 0..metrics.height {
+ let x = x + i as u32 + glpyh.x as u32;
+ if x >= self.width() {
+ continue;
+ }
+ let y = y + j as u32 + glpyh.y as u32;
+ if y >= self.height() {
+ continue;
+ }
+
+ // SAFETY: the rasterizer kinda promises that metrics width and height are in bounds
+ let fill = unsafe { float(*bitmap.get_unchecked(j * metrics.width + i)) };
+ // SAFETY: we clampin
+ let bg = unsafe { &mut *(self.pixel_mut(x, y).as_mut_ptr() as *mut [u8; N]) };
+ // SAFETY: fill is 0..=1
+ *bg = unsafe { bg.wam(color, *(FF32::one() - fill), fill) };
+ }
+ }
+ }
+ }
+}
+
+impl<const N: usize, T> Image<T, N> {
+ /// Draw text.
+ ///
+ /// ```
+ /// # use fimg::Image;
+ /// let font = fontdue::Font::from_bytes(
+ /// &include_bytes!("../../data/CascadiaCode.ttf")[..],
+ /// fontdue::FontSettings {
+ /// scale: 200.0,
+ /// ..Default::default()
+ /// },
+ /// ).unwrap();
+ /// let mut i: Image<_, 4> = Image::alloc(750, 250).boxed();
+ /// i.text(50, 10, 200.0, &font, "hello", [0, 0, 0, 255]);
+ /// # assert_eq!(&**i.buffer(), include_bytes!("../../tdata/text.imgbuf"));
+ /// ```
+ pub fn text<const P: usize>(
+ &mut self,
+ x: u32,
+ y: u32,
+ size: f32,
+ font: &Font,
+ text: &str,
+ color: [u8; P],
+ ) where
+ Image<T, N>: Text<P>,
+ {
+ Text::text(self, x, y, size, font, text, color)
+ }
+}