Implement dynamic font support /font/<name>/<start>-<end>

This will NOT compile until stadiamaps/sdf_font_tools#13 is merged and published

This implements dynamic font protobuf generation, allowing users to request font ranges on the fly, and combining them in any order, e.g. `Font1,Font2,Font3`, same as with sprites and tiles

This is a first iteration, without any multithreading support. In theory, this could be done far faster by generating SDFs with multiple threads.

Current steps:
* during init, figure out all glyphs available in each font, and store them as a bitset
* during request:
  * combine requested bitsets to figure out which glyph should come from which font file
  * load those glyphs from files (using a single instance of the freetype lib)
  * convert them to SDFs and package them into a protobuf

Cargo.toml

@@ -18,6 +18,7 @@ actix-rt = "2"
 actix-web = "4"
 anyhow = "1.0"
 async-trait = "0.1"
+bit-set = "0.5.3"
 brotli = "3"
 cargo-husky = { version = "1", features = ["user-hooks"], default-features = false }
 clap = { version = "4", features = ["derive"] }
@@ -36,6 +37,7 @@ log = "0.4"
 martin-mbtiles = { path = "./martin-mbtiles", version = "0.6.0", default-features = false }
 martin-tile-utils = { path = "./martin-tile-utils", version = "0.1.0" }
 num_cpus = "1"
+pbf_font_tools = { version = "2.4.0", features = ["freetype"], path = "../sdf_font_tools/pbf_font_tools" }
 pmtiles = { version = "0.3", features = ["mmap-async-tokio", "tilejson"] }
 postgis = "0.9"
 postgres = { version = "0.19", features = ["with-time-0_3", "with-uuid-1", "with-serde_json-1"] }

martin-mbtiles/src/errors.rs

@@ -5,6 +5,8 @@ use sqlite_hashes::rusqlite;
 
 use crate::MbtType;
 
+use crate::mbtiles::MbtType;
+
 #[derive(thiserror::Error, Debug)]
 pub enum MbtError {
     #[error("The source and destination MBTiles files are the same: {}", .0.display())]

martin/Cargo.toml

@@ -57,6 +57,7 @@ actix-rt.workspace = true
 actix-web.workspace = true
 actix.workspace = true
 async-trait.workspace = true
+bit-set.workspace = true
 brotli.workspace = true
 clap.workspace = true
 deadpool-postgres.workspace = true
@@ -69,6 +70,7 @@ log.workspace = true
 martin-mbtiles.workspace = true
 martin-tile-utils.workspace = true
 num_cpus.workspace = true
+pbf_font_tools.workspace = true
 pmtiles.workspace = true
 postgis.workspace = true
 postgres-protocol.workspace = true

martin/src/args/root.rs

@@ -10,7 +10,7 @@ use crate::args::srv::SrvArgs;
 use crate::args::State::{Ignore, Share, Take};
 use crate::config::Config;
 use crate::file_config::FileConfigEnum;
-use crate::{Error, Result};
+use crate::{Error, OneOrMany, Result};
 
 #[derive(Parser, Debug, PartialEq, Default)]
 #[command(about, version)]
@@ -44,6 +44,9 @@ pub struct MetaArgs {
     /// Export a directory with SVG files as a sprite source. Can be specified multiple times.
     #[arg(short, long)]
     pub sprite: Vec<PathBuf>,
+    /// Export a directory with font files as a font source. Can be specified multiple times.
+    #[arg(short, long)]
+    pub font: Vec<PathBuf>,
 }
 
 impl Args {
@@ -81,6 +84,10 @@ impl Args {
             config.sprites = FileConfigEnum::new(self.meta.sprite);
         }
 
+        if !self.meta.font.is_empty() {
+            config.fonts = OneOrMany::new_opt(self.meta.font);
+        }
+
         cli_strings.check()
     }
 }

martin/src/config.rs

@@ -2,14 +2,15 @@ use std::collections::HashMap;
 use std::fs::File;
 use std::future::Future;
 use std::io::prelude::*;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 use std::pin::Pin;
 
 use futures::future::try_join_all;
 use serde::{Deserialize, Serialize};
 use subst::VariableMap;
 
 use crate::file_config::{resolve_files, FileConfigEnum};
+use crate::fonts::{resolve_fonts, FontSources};
 use crate::mbtiles::MbtSource;
 use crate::pg::PgConfig;
 use crate::pmtiles::PmtSource;
@@ -24,6 +25,7 @@ pub type UnrecognizedValues = HashMap<String, serde_yaml::Value>;
 pub struct AllSources {
     pub sources: Sources,
     pub sprites: SpriteSources,
+    pub fonts: FontSources,
 }
 
 #[derive(Clone, Debug, Default, PartialEq, Serialize, Deserialize)]
@@ -43,6 +45,9 @@ pub struct Config {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub sprites: Option<FileConfigEnum>,
 
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub fonts: Option<OneOrMany<PathBuf>>,
+
     #[serde(flatten)]
     pub unrecognized: UnrecognizedValues,
 }
@@ -83,6 +88,14 @@ impl Config {
             false
         };
 
+        any |= if let Some(cfg) = &mut self.fonts {
+            // TODO: support for unrecognized fonts?
+            // res.extend(cfg.finalize("fonts.")?);
+            !cfg.is_empty()
+        } else {
+            false
+        };
+
         if any {
             Ok(res)
         } else {
@@ -123,6 +136,7 @@ impl Config {
                 })
                 .sort(),
             sprites: resolve_sprites(&mut self.sprites)?,
+            fonts: resolve_fonts(&mut self.fonts)?,
         })
     }
 }