add text to show()

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "fimg"
-version = "0.4.23"
+version = "0.4.24"
 authors = ["bend-n <bend.n@outlook.com>"]
 license = "MIT"
 edition = "2021"
@@ -57,7 +57,7 @@ scale = ["fr"]
 save = ["png"]
 text = ["fontdue"]
 blur = ["stackblur-iter"]
-real-show = ["minifb"]
+real-show = ["minifb", "text"]
 default = ["save", "scale"]
 
 [profile.release]

src/convert.rs

@@ -6,14 +6,15 @@ fn map<const A: usize, const B: usize>(image: Image<&[u8], A>) -> Image<Box<[u8]
 where
     [u8; B]: PFrom<A>,
 {
-    let buffer = image
-        .chunked()
-        .copied()
-        .flat_map(<[u8; B] as PFrom<A>>::pfrom)
-        .collect::<Vec<_>>()
-        .into();
-    // SAFETY: ctor
-    unsafe { Image::new(image.width, image.height, buffer) }
+    // SAFETY: size unchanged, just change pixels
+    unsafe {
+        image.mapped(|buf| {
+            buf.array_chunks::<A>()
+                .copied()
+                .flat_map(<[u8; B] as PFrom<A>>::pfrom)
+                .collect()
+        })
+    }
 }
 
 macro_rules! convert {
@@ -64,12 +65,12 @@ boxconv!(4 => 2);
 boxconv!(4 => 3);
 
 #[inline]
-const fn pack([r, g, b, a]: [u8; 4]) -> u32 {
+pub const fn pack([r, g, b, a]: [u8; 4]) -> u32 {
     ((a as u32) << 24) | ((r as u32) << 16) | ((g as u32) << 8) | (b as u32)
 }
 
 #[inline]
-const fn unpack(n: u32) -> [u8; 4] {
+pub const fn unpack(n: u32) -> [u8; 4] {
     [
         ((n >> 16) & 0xFF) as u8,
         ((n >> 8) & 0xFF) as u8,

src/drawing/text.rs

@@ -1,19 +1,60 @@
 //! text raster
 
 use crate::{
+    convert::{pack, unpack},
     pixels::{float, Wam},
     Image,
 };
 use fontdue::{layout::TextStyle, Font};
 use umath::{generic_float::Constructors, FF32};
 
+impl Image<&mut [u32], 1> {
+    pub(crate) fn text_u32(
+        &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 = unsafe { unpack(*self.buffer.get_unchecked(self.at(x, y))) };
+                    // SAFETY: see above
+                    *unsafe { self.buffer.get_unchecked_mut(self.at(x, y)) } =
+                        // SAFETY: fill is 0..=1
+                        pack(unsafe { bg.wam(color, FF32::one() - fill, fill) });
+                }
+            }
+        }
+    }
+}
+
 impl<const N: usize, T: AsMut<[u8]> + AsRef<[u8]>> Image<T, N> {
     /// Draw text.
     ///
     /// ```
     /// # use fimg::Image;
     /// let font = fontdue::Font::from_bytes(
-    ///     &include_bytes!("../../tdata/CascadiaCode.ttf")[..],
+    ///     &include_bytes!("../../data/CascadiaCode.ttf")[..],
     ///     fontdue::FontSettings {
     ///         scale: 200.0,
     ///         ..Default::default()

src/lib.rs

@@ -56,7 +56,8 @@
     array_windows,
     doc_auto_cfg,
     const_option,
-    array_chunks
+    array_chunks,
+    let_chains
 )]
 #![warn(
     clippy::undocumented_unsafe_blocks,
@@ -243,21 +244,52 @@ impl<T, const CHANNELS: usize> Image<T, CHANNELS> {
     pub unsafe fn buffer_mut(&mut self) -> &mut T {
         &mut self.buffer
     }
+
+    /// # Safety
+    ///
+    /// the output index is not guranteed to be in bounds
+    #[inline]
+    fn at(&self, x: u32, y: u32) -> usize {
+        debug_assert!(x < self.width(), "x out of bounds");
+        debug_assert!(y < self.height(), "y out of bounds");
+        #[allow(clippy::multiple_unsafe_ops_per_block)]
+        // SAFETY: me when uncheck math: 😧 (FIXME)
+        let index = unsafe {
+            let w = self.width();
+            // y * w + x
+            let tmp = (y as usize).unchecked_mul(w as usize);
+            tmp.unchecked_add(x as usize)
+        };
+        // SAFETY: 🧐 is unsound? 😖
+        unsafe { index.unchecked_mul(CHANNELS) }
+    }
+
+    /// # Safety
+    /// keep the buffer size the same
+    unsafe fn map<U, const N: usize, F: FnOnce(&T) -> U>(&self, f: F) -> Image<U, N> {
+        // SAFETY: we dont change anything, why check
+        unsafe { Image::new(self.width, self.height, f(self.buffer())) }
+    }
+
+    unsafe fn mapped<U, const N: usize, F: FnOnce(T) -> U>(self, f: F) -> Image<U, N> {
+        // SAFETY: we dont change anything, why check
+        unsafe { Image::new(self.width, self.height, f(self.buffer)) }
+    }
 }
 
 impl<const CHANNELS: usize, T: Clone> Image<&[T], CHANNELS> {
     /// Allocate a new `Image<Vec<T>>` from this imageref.
     pub fn to_owned(&self) -> Image<Vec<T>, CHANNELS> {
-        // SAFETY: we have been constructed already, so must be valid
-        unsafe { Image::new(self.width, self.height, self.buffer.to_vec()) }
+        // SAFETY: size not changed
+        unsafe { self.map(|b| b.to_vec()) }
     }
 }
 
 impl<const CHANNELS: usize, T: Clone> Image<&mut [T], CHANNELS> {
     /// Allocate a new `Image<Vec<T>>` from this mutable imageref.
     pub fn to_owned(&self) -> Image<Vec<T>, CHANNELS> {
-        // SAFETY: we have been constructed already, so must be valid
-        unsafe { Image::new(self.width, self.height, self.buffer.to_vec()) }
+        // SAFETY: size not changed
+        unsafe { self.map(|b| b.to_vec()) }
     }
 }
 
@@ -301,16 +333,16 @@ impl<const CHANNELS: usize> Image<&[u8], CHANNELS> {
 impl<const CHANNELS: usize, const N: usize> Image<[u8; N], CHANNELS> {
     /// Box this array image.
     pub fn boxed(self) -> Image<Box<[u8]>, CHANNELS> {
-        // SAFETY: ctor
-        unsafe { Image::new(self.width, self.height, Box::new(self.buffer)) }
+        // SAFETY: size not changed
+        unsafe { self.mapped(|b| b.into()) }
     }
 }
 
 impl<const CHANNELS: usize> Image<&[u8], CHANNELS> {
     /// Box this image.
     pub fn boxed(self) -> Image<Box<[u8]>, CHANNELS> {
-        // SAFETY: ctor
-        unsafe { Image::new(self.width, self.height, self.buffer.into()) }
+        // SAFETY: size not changed
+        unsafe { self.mapped(|b| b.into()) }
     }
 }
 
@@ -318,7 +350,7 @@ impl<const CHANNELS: usize> Image<Vec<u8>, CHANNELS> {
     /// Box this owned image.
     pub fn boxed(self) -> Image<Box<[u8]>, CHANNELS> {
         // SAFETY: ctor
-        unsafe { Image::new(self.width, self.height, self.buffer.into_boxed_slice()) }
+        unsafe { self.mapped(|b| b.into()) }
     }
 }
 
@@ -367,31 +399,11 @@ impl<T: AsRef<[u8]>, const CHANNELS: usize> Image<T, CHANNELS> {
     #[inline]
     fn slice(&self, x: u32, y: u32) -> impl SliceIndex<[u8], Output = [u8]> {
         let index = self.at(x, y);
+        debug_assert!(self.len() > index);
         // SAFETY: as long as the buffer isnt wrong, this is 😄
         index..unsafe { index.unchecked_add(CHANNELS) }
     }
 
-    /// # Safety
-    ///
-    /// the output index is not guranteed to be in bounds
-    #[inline]
-    fn at(&self, x: u32, y: u32) -> usize {
-        debug_assert!(x < self.width(), "x out of bounds");
-        debug_assert!(y < self.height(), "y out of bounds");
-        #[allow(clippy::multiple_unsafe_ops_per_block)]
-        // SAFETY: me when uncheck math: 😧 (FIXME)
-        let index = unsafe {
-            let w = self.width();
-            // y * w + x
-            let tmp = (y as usize).unchecked_mul(w as usize);
-            tmp.unchecked_add(x as usize)
-        };
-        // SAFETY: 🧐 is unsound? 😖
-        let index = unsafe { index.unchecked_mul(CHANNELS) };
-        debug_assert!(self.len() > index);
-        index
-    }
-
     /// Procure a [`ImageCloner`].
     #[must_use = "function does not modify the original image"]
     pub fn cloner(&self) -> ImageCloner<'_, CHANNELS> {
@@ -539,8 +551,8 @@ impl<const CHANNELS: usize> Image<Vec<u8>, CHANNELS> {
     /// Consumes and leaks this image, returning a reference to the image.
     #[must_use = "not using the returned reference is a memory leak"]
     pub fn leak(self) -> Image<&'static mut [u8], CHANNELS> {
-        // SAFETY: ctor
-        unsafe { Image::new(self.width, self.height, self.buffer.leak()) }
+        // SAFETY: size unchanged
+        unsafe { self.mapped(Vec::leak) }
     }
 }
 
@@ -548,8 +560,8 @@ impl<const CHANNELS: usize, T: ?Sized> Image<Box<T>, CHANNELS> {
     /// Consumes and leaks this image, returning a reference to the image.
     #[must_use = "not using the returned reference is a memory leak"]
     pub fn leak(self) -> Image<&'static mut T, CHANNELS> {
-        // SAFETY: ctor
-        unsafe { Image::new(self.width, self.height, Box::leak(self.buffer)) }
+        // SAFETY: size unchanged
+        unsafe { self.mapped(Box::leak) }
     }
 }
 

src/show.rs

@@ -2,10 +2,13 @@ use crate::Image;
 
 #[cfg(feature = "real-show")]
 mod real {
-    use crate::Image;
+    use crate::{pixels::convert::PFrom, Image};
     use minifb::{Key, Window};
 
-    pub fn show(i: Image<&[u32], 1>) {
+    pub fn show<const CHANNELS: usize>(i: Image<&[u8], CHANNELS>)
+    where
+        [u8; 4]: PFrom<CHANNELS>,
+    {
         let mut win = Window::new(
             "show",
             i.width() as usize,
@@ -13,9 +16,44 @@ mod real {
             Default::default(),
         )
         .unwrap();
-        win.limit_update_rate(Some(std::time::Duration::from_millis(100)));
+        let font = fontdue::Font::from_bytes(
+            &include_bytes!("../data/CascadiaCode.ttf")[..],
+            fontdue::FontSettings {
+                scale: 12.0,
+                ..Default::default()
+            },
+        )
+        .unwrap();
         while win.is_open() && !win.is_key_down(Key::Q) && !win.is_key_down(Key::Escape) {
-            win.update_with_buffer(&i.buffer, i.width() as usize, i.height() as usize)
+            let mut buf = Image::<Box<[u32]>, 1>::from(i.as_ref());
+
+            if !win.is_key_down(Key::H)
+                && let Some((x, y)) = win
+                    .get_mouse_pos(minifb::MouseMode::Discard)
+                    .map(|(x, y)| (x.round() as u32, y.round() as u32))
+                    .map(|(x, y)| (x.min(i.width()), y.min(i.height())))
+            {
+                // SAFETY: ctor
+                unsafe { Image::new(buf.width, buf.height, &mut *buf.buffer) }.text_u32(
+                    5,
+                    i.height() - 20,
+                    12.0,
+                    &font,
+                    &format!(
+                        "P ({x}, {y}), {}",
+                        // SAFETY: clampd
+                        match unsafe { &i.pixel(x, y)[..] } {
+                            [y] => format!("(Y {y})"),
+                            [y, a] => format!("(Y {y} A {a})"),
+                            [r, g, b] => format!("(R {r} G {g} B {b})"),
+                            [r, g, b, a] => format!("(R {r} G {g} B {b} A {a})"),
+                            _ => unreachable!(),
+                        }
+                    ),
+                    [238, 232, 213, 255],
+                )
+            }
+            win.update_with_buffer(&buf.buffer, i.width() as usize, i.height() as usize)
                 .expect("window update fail");
         }
     }
@@ -93,7 +131,7 @@ macro_rules! show {
             /// if the window is un creatable
             pub fn show(self) -> Self {
                 #[cfg(feature = "real-show")]
-                real::show(r(&self.as_ref().into()));
+                real::show(self.as_ref());
                 #[cfg(not(feature = "real-show"))]
                 fake::show!(self);
                 self
@@ -117,7 +155,7 @@ impl Image<Box<[u32]>, 1> {
     /// if the window is un creatable
     pub fn show(self) -> Self {
         #[cfg(feature = "real-show")]
-        real::show(r(&self));
+        real::show(Image::<Box<[u8]>, 4>::from(r(&self)).as_ref());
         #[cfg(not(feature = "real-show"))]
         fake::show!(Image::<Box<[u8]>, 4>::from(r(&self)));
         self