diff --git a/src/main.rs b/src/main.rs
index 6fb1cd4..21e3a60 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -5,8 +5,11 @@ use crate::quad_tree::QuadTree;
 use non_nan_float::NonNaNF32;
 use std::{
     borrow::Borrow,
+    cell::RefCell,
     collections::{BTreeMap, BTreeSet, HashMap, HashSet},
     fmt,
+    num::NonZero,
+    rc::Rc,
     sync::OnceLock,
 };
 
@@ -96,6 +99,15 @@ macro_rules! make_enum_font {
         }
 
         impl $Font {
+            fn new(font_name: &str, size: NonNaNF32) -> Self {
+                match (font_name, size.get()) {
+                    $($(($known_font_name, $known_font_size) => Self::$KnownFont,)*)*
+                    _ => Self::Other {
+                        font_name: Box::from(font_name),
+                        size,
+                    }
+                }
+            }
             const fn size(&self) -> f32 {
                 match *self {
                     Self::$Other { size, .. } => size.get(),
@@ -535,7 +547,6 @@ impl Font {
 struct Char {
     font: Font,
     text: String,
-    adv: NonNaNF32,
     min_x: NonNaNF32,
     min_y: NonNaNF32,
     max_x: NonNaNF32,
@@ -1711,4 +1722,178 @@ impl TextSection {
     }
 }
 
-fn main() {}
+#[derive(Clone, Debug, Default)]
+struct MyDevice {
+    chars: Rc<RefCell<Vec<Char>>>,
+}
+
+impl MyDevice {
+    fn text(&mut self, text: &mupdf::Text, cmt: mupdf::Matrix) {
+        for span in text.spans() {
+            let span_font = span.font();
+            let font_name = span_font.name();
+            const ROUND_FACTOR: f32 = 1000.0;
+            let Some(size) =
+                NonNaNF32::new((span.trm().expansion() * ROUND_FACTOR).round() / ROUND_FACTOR)
+            else {
+                continue;
+            };
+            let font = Font::new(font_name, size);
+            for item in span.items() {
+                let Some(ch) = u32::try_from(item.ucs())
+                    .ok()
+                    .and_then(|v| char::try_from(v).ok())
+                else {
+                    continue;
+                };
+                let mut m = span.trm();
+                m.e = item.x();
+                m.f = item.y();
+                m.concat(cmt);
+                let (min_x, min_y, max_x, max_y) = match span.wmode() {
+                    mupdf::WriteMode::Horizontal => {
+                        todo!();
+                    }
+                    mupdf::WriteMode::Vertical => todo!(),
+                };
+                self.chars.borrow_mut().push(Char {
+                    font,
+                    text: String::from(ch),
+                    min_x,
+                    min_y,
+                    max_x,
+                    max_y,
+                });
+            }
+        }
+    }
+}
+
+impl mupdf::NativeDevice for MyDevice {
+    fn fill_path(
+        &mut self,
+        path: &mupdf::Path,
+        even_odd: bool,
+        cmt: mupdf::Matrix,
+        color_space: &mupdf::Colorspace,
+        color: &[f32],
+        alpha: f32,
+        cp: mupdf::ColorParams,
+    ) {
+        // TODO
+    }
+
+    fn stroke_path(
+        &mut self,
+        path: &mupdf::Path,
+        stroke_state: &mupdf::StrokeState,
+        cmt: mupdf::Matrix,
+        color_space: &mupdf::Colorspace,
+        color: &[f32],
+        alpha: f32,
+        cp: mupdf::ColorParams,
+    ) {
+        // TODO
+    }
+
+    fn clip_path(
+        &mut self,
+        path: &mupdf::Path,
+        even_odd: bool,
+        cmt: mupdf::Matrix,
+        scissor: mupdf::Rect,
+    ) {
+        // TODO
+    }
+
+    fn clip_stroke_path(
+        &mut self,
+        path: &mupdf::Path,
+        stroke_state: &mupdf::StrokeState,
+        cmt: mupdf::Matrix,
+        scissor: mupdf::Rect,
+    ) {
+        // TODO
+    }
+
+    fn fill_text(
+        &mut self,
+        text: &mupdf::Text,
+        cmt: mupdf::Matrix,
+        _color_space: &mupdf::Colorspace,
+        _color: &[f32],
+        _alpha: f32,
+        _cp: mupdf::ColorParams,
+    ) {
+        self.text(text, cmt);
+    }
+
+    fn stroke_text(
+        &mut self,
+        text: &mupdf::Text,
+        _stroke_state: &mupdf::StrokeState,
+        cmt: mupdf::Matrix,
+        _color_space: &mupdf::Colorspace,
+        _color: &[f32],
+        _alpha: f32,
+        _cp: mupdf::ColorParams,
+    ) {
+        self.text(text, cmt);
+    }
+
+    fn clip_text(&mut self, text: &mupdf::Text, cmt: mupdf::Matrix, _scissor: mupdf::Rect) {
+        self.text(text, cmt);
+    }
+
+    fn clip_stroke_text(
+        &mut self,
+        text: &mupdf::Text,
+        _stroke_state: &mupdf::StrokeState,
+        cmt: mupdf::Matrix,
+        _scissor: mupdf::Rect,
+    ) {
+        self.text(text, cmt);
+    }
+
+    fn ignore_text(&mut self, text: &mupdf::Text, cmt: mupdf::Matrix) {
+        self.text(text, cmt);
+    }
+}
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let args: Vec<String> = std::env::args().collect();
+    let page_numbers: Option<Box<dyn Iterator<Item = NonZero<u32>>>> = if 2 < args.len() {
+        Some(if let Some((start, end)) = args[2].split_once(":") {
+            let start: NonZero<u32> = start.trim().parse()?;
+            let end: NonZero<u32> = end.trim().parse()?;
+            Box::new(
+                (start.get()..end.get()).map(|v| NonZero::new(v).expect("known to be non-zero")),
+            )
+        } else {
+            Box::new(
+                Result::<BTreeSet<NonZero<u32>>, _>::from_iter(
+                    args[2].split(",").map(|v| v.trim().parse()),
+                )?
+                .into_iter(),
+            )
+        })
+    } else {
+        None
+    };
+    let document = mupdf::Document::open(&args[1])?;
+    let pages: Vec<_> = document.pages()?.collect::<Result<_, _>>()?;
+    let page_numbers = page_numbers.unwrap_or_else(|| {
+        Box::new(
+            (0..pages.len()).map(|i| NonZero::new((i + 1) as u32).expect("known to be non-zero")),
+        )
+    });
+    for page_num in page_numbers {
+        let device = MyDevice::default();
+        pages[page_num.get() as usize - 1].run(
+            &mupdf::Device::from_native(device.clone())?,
+            &mupdf::Matrix::IDENTITY,
+        )?;
+        println!("{device:?}");
+    }
+    Ok(())
+}