finish glyph parsing

src/font.rs

@@ -51,12 +51,13 @@ impl Font {
 	pub fn new(file: File) -> bincode::Result<Self> {
 		let mut buf_reader = BufReader::new(file.try_clone()?);
 		let table_directory = TableDirectory::new(&mut buf_reader)?;
+		debug!("{table_directory:#?}");
 
 		let font_header: FontHeader = table_directory.get_table(&file)?;
 		debug!("{font_header:#?}");
 
 		let character_map = table_directory.get_table(&file)?;
-		debug!("{character_map:#?}");
+		// debug!("{character_map:#?}");
 
 		let maximum_profile: MaximumProfile = table_directory.get_table(&file)?;
 		debug!("{maximum_profile:#?}");

src/font/glyph_data.rs

@@ -1,8 +1,8 @@
-use std::{collections::HashMap, fs::File, io::{BufReader, Read, Seek, SeekFrom}, iter::zip, slice::Iter};
+use std::{collections::HashMap, fs::File, io::{BufReader, Read, Seek, SeekFrom}, iter::{zip, Peekable}, slice::Iter};
 
 use bincode::{ErrorKind, Result};
 use bitfield::bitfield;
-use log::{debug, info};
+use log::{debug, info, warn};
 use serde::Deserialize;
 
 use super::{deserialize, deserialize_vec, index_to_location::IndexToLocation, table_directory::{FontTable, TableDirectoryRecord}};
@@ -56,35 +56,37 @@ impl<'a> Iterator for GlyphFlags<'a> {
 
 	fn next(&mut self) -> Option<Self::Item> {
 		if self.current_item >= self.flags.len() {
+			debug!("no more logical flags");
 			return None;
 		}
 
 		let current = &self.flags[self.current_item];
 
-		if self.repetitions < current.repeat as u16 {
+		if self.repetitions <= current.repeat as u16 {
+			if self.repetitions > 0 {
+				debug!("flag #{} repeated {} times", self.current_item, self.repetitions);
+			} else {
+				debug!("yield flag #{}", self.current_item);
+			}
+
 			self.repetitions += 1;
 			return Some(current.flags);
 		}
 
-		self.current_item += 1;
-		if self.current_item >= self.flags.len() {
-			return None;
-		}
-
-		let current = &self.flags[self.current_item];
 		self.repetitions = 0;
-
-		Some(current.flags)
-		
+		self.current_item += 1;
+		self.next()
 	}
 }
 
-#[derive(Debug)]
+#[derive(Debug, Copy, Clone)]
 pub struct GlyphPoint {
 	pub x: i32,
 	pub y: i32,
 
-	pub on_curve: bool
+	pub on_curve: bool,
+	pub is_virtual: bool,
+	pub is_endpoint: bool,
 }
 
 #[derive(Debug)]
@@ -100,7 +102,7 @@ impl SimpleGlyph {
 		let mut flags: Vec<GlyphFlag> = vec![];
 
 		let mut points_processed: usize = 0;
-		while points_processed < num_points {
+		while points_processed <= num_points {
 			let flag: GlyphFlagData = deserialize(reader.by_ref())?;
 
 			let repetitions: u8 = if flag.repeat() { deserialize(reader.by_ref())? } else { 0 };
@@ -118,28 +120,39 @@ impl SimpleGlyph {
 	}
 
 	fn read_coordinates<R: Read + Seek>(reader: &mut R, flags: GlyphFlags, is_y: bool) -> Result<Vec<(i32, bool)>> {
+		debug!("reading batch of {} coordinates at {}", if is_y { "y" } else { "x" }, reader.stream_position()?);
 		let mut coordinates: Vec<(i32, bool)> = vec![];
 		let mut current_coordinate = 0i32;
 
 		for flag in flags {
+			debug!("reading next coordinate");
+
 			let short_vec = if is_y { flag.y_short() } else { flag.x_short() };
 			let same_or_positive = if is_y { flag.y_same_or_positive() } else { flag.x_same_or_positive() };
 
+			debug!("short vec: {short_vec}, same or positive: {same_or_positive}");
+
 			if short_vec {
 				let sign: i32 = if same_or_positive { 1 } else { -1 };
 				let delta = sign * (deserialize::<_, u8>(reader.by_ref())? as i32);
 
+				debug!("delta = (u8){delta}");
+
 				current_coordinate += delta;
 				coordinates.push((current_coordinate, flag.on_curve()));
 			} else {
 				if same_or_positive {
+					debug!("coordinate is repeated");
 					coordinates.push((current_coordinate, flag.on_curve()));
 				} else {
 					let delta: i16 = deserialize(reader.by_ref())?;
+					debug!("delta = (i16){delta}");
 					current_coordinate += delta as i32;
 					coordinates.push((current_coordinate, flag.on_curve()));
 				}
 			}
+
+			debug!("current coordinate is now {current_coordinate}");
 		}
 
 		Ok(coordinates)
@@ -158,11 +171,24 @@ impl SimpleGlyph {
 		let x_coords = SimpleGlyph::read_coordinates(reader, GlyphFlags::new(&flags), false)?;
 		let y_coords = SimpleGlyph::read_coordinates(reader, GlyphFlags::new(&flags), true)?;
 
+		if x_coords.len() != *end_points.last().unwrap() as usize + 1 {
+			warn!("expected {} x coordinates, got {} instead", end_points.last().unwrap() + 1, x_coords.len());
+		}
+
+		if y_coords.len() != *end_points.last().unwrap() as usize + 1 {
+			warn!("expected {} y coordinates, got {} instead", end_points.last().unwrap() + 1, y_coords.len());
+		}
+
+		let mut current_point: u16 = 0;
 		let coordinates = zip(x_coords.iter().cloned(), y_coords.iter().cloned())
 			.map(|(x, y)| {
-				GlyphPoint {
-					x: x.0, y: y.0, on_curve: x.1
-				}
+				let point = GlyphPoint {
+					x: x.0, y: y.0, on_curve: x.1, is_endpoint: end_points.contains(&current_point), is_virtual: false
+				};
+
+				current_point += 1;
+
+				point
 			});
 
 		// coordinates.for_each(|point| debug!("({}, {}, {})", point.x, point.y, if point.on_curve { "on" } else { "off" }));
@@ -173,21 +199,44 @@ impl SimpleGlyph {
 	pub fn iter<'a>(&'a self) -> SimpleGlyphIter<'a> {
 		SimpleGlyphIter {
 			glyph: self,
-			iter: self.points.iter()
+			last_point: None,
+			iter: self.points.iter().peekable()
 		}
 	}
 }
 
 struct SimpleGlyphIter<'a> {
 	glyph: &'a SimpleGlyph,
-	iter: Iter<'a, GlyphPoint>
+	last_point: Option<GlyphPoint>,
+	iter: Peekable<Iter<'a, GlyphPoint>>
 }
 
 impl<'a> Iterator for SimpleGlyphIter<'a> {
-	type Item = &'a GlyphPoint;
+	type Item = GlyphPoint;
 
 	fn next(&mut self) -> Option<Self::Item> {
-		self.iter.next()
+		if let Some(last_point) = self.last_point {
+			let Some(&next_point) = self.iter.peek() else {
+				return None
+			};
+
+			if !last_point.on_curve && !next_point.on_curve {
+				// Interpolate a point
+				let virtual_point = GlyphPoint {
+					x: last_point.x + (next_point.x - last_point.x) / 2,
+					y: last_point.y + (next_point.y - last_point.y) / 2,
+					is_endpoint: false,
+					is_virtual: true,
+					on_curve: true
+				};
+
+				self.last_point = Some(virtual_point);
+				return self.last_point;
+			}
+		}
+
+		self.last_point = self.iter.next().copied();
+		self.last_point
 	}
 }
 
@@ -204,7 +253,7 @@ pub struct Glyph {
 }
 
 impl Glyph {
-	pub fn iter<'a>(&'a self) -> Box<dyn Iterator<Item = &'a GlyphPoint> + 'a> {
+	pub fn iter<'a>(&'a self) -> Box<dyn Iterator<Item = GlyphPoint> + 'a> {
 		Box::new(
 			match &self.data {
 				GlyphData::Simple(glyph) => glyph.iter(),
@@ -236,14 +285,28 @@ impl GlyphTable {
 		let header: GlyphHeader = deserialize(self.data_source.get_ref())?;
 		debug!("glyph header: {header:#?}");
 
-		if header.num_countours >= 0 {
+		let result = if header.num_countours >= 0 {
 			Ok(Glyph {
 				data: GlyphData::Simple(SimpleGlyph::new(&header, self.data_source.by_ref())?),
 				header
 			})
 		} else {
 			todo!();
+		};
+
+		// sanity check
+		let stream_pos = self.data_source.stream_position()?;
+		let Some(next_offset) = location.get_offset(glyph_id + 1) else {
+			warn!("Failed to perform sanity check after glyph parsing");
+			return result;
+		};
+
+		let remaining_bytes = stream_pos as i64 - (self.offset + next_offset) as i64;
+		if remaining_bytes != 0 {
+			warn!("sanity check failed, there are still {remaining_bytes} bytes remaining in this glyph entry (read head: {}, table off: {}, location: [{offset}, {next_offset}])", stream_pos, self.offset);
 		}
+
+		result
 	}
 }
 

src/writer.rs

@@ -11,8 +11,8 @@ pub trait Visitor {
 
 	fn write(&mut self, glyph: &Glyph) {
 		self.write_prefix(&glyph.header);
-		
-		glyph.iter().for_each(|point| self.write_point(point));
+
+		glyph.iter().for_each(|point| self.write_point(&point));
 
 		self.write_suffix();
 	}

src/writer/svg.rs

@@ -6,6 +6,9 @@ use super::Visitor;
 
 pub struct SvgWriter {
 	first_point: bool,
+	last_on_curve: bool,
+	final_point: Option<(i32, i32)>,
+	final_control: Option<(i32, i32)>,
 	writer: BufWriter<File>
 }
 
@@ -13,6 +16,9 @@ impl SvgWriter {
 	pub fn new(file: File) -> Self {
 		SvgWriter {
 			first_point: true,
+			last_on_curve: false,
+			final_control: None,
+			final_point: None,
 			writer: BufWriter::new(file)
 		}
 	}
@@ -23,26 +29,56 @@ impl Visitor for SvgWriter {
 		write!(
 			self.writer,
 			"<svg width=\"1000\" height=\"1000\" viewBox=\"{} {} {} {}\" xmlns=\"http://www.w3.org/2000/svg\"><path d=\"",
-			header.xmin, header.ymin,
+			header.xmin, -header.ymax,
 			header.xmax - header.xmin,
 			header.ymax - header.ymin
 		);
 	}
 
 	fn write_point(&mut self, point: &GlyphPoint) {
-		if !point.on_curve {
-			return
+		if self.final_point.is_none() && point.on_curve {
+			self.final_point = Some((point.x, point.y));
 		}
 
-		let prefix = if self.first_point { "M" } else { "L" };
+		if self.first_point && self.final_control.is_none() && !point.on_curve {
+			self.final_control = Some((point.x, point.y));
+		}
+
+		if self.first_point {
+			if !point.on_curve {
+				return;
+			}
+
+			write!(self.writer, "M{} {} ", point.x, -point.y);
+			self.first_point = false;
+			self.last_on_curve = true;
+			return;
+		}
+
+		let prefix = if point.on_curve { if self.last_on_curve { "L" } else { "" } } else { "Q" };
+		self.last_on_curve = point.on_curve;
 
 		write!(
 			self.writer,
 			"{prefix}{} {} ",
-			point.x, point.y
+			point.x, -point.y
 		);
 
-		self.first_point = false;
+		if point.is_endpoint {
+			if let Some(final_control) = self.final_control {
+				if let Some(final_point) = self.final_point {
+					write!(self.writer, "Q{} {} {} {} ", final_control.0, -final_control.1, final_point.0, -final_point.1);
+				} else {
+					write!(self.writer, "Z ");
+				}
+			} else {
+				write!(self.writer, "Z ");
+			}
+
+			self.final_point = None;
+			self.final_control = None;
+		}
+		self.first_point = point.is_endpoint;
 	}
 
 	fn write_suffix(&mut self) {