cache tilesHEADmaster

2 files changed, 25 insertions, 7 deletions

diff --git a/src/tiling.rs b/src/tiling.rs
index 8ab7fc3..9a58ebd 100644
--- a/src/tiling.rs
+++ b/src/tiling.rs
@@ -1,4 +1,8 @@
-use std::{fs::File, io::Read};
+use std::{
+    fs::File,
+    io::Read,
+    path::{Path, PathBuf},
+};
 
 use log::info;
 
@@ -10,16 +14,30 @@ pub struct Tiler {
 
 impl Tiler {
     pub fn new(renderer: Renderer) -> Self {
+        std::fs::create_dir_all("tiles").unwrap();
         Self { renderer }
     }
-    pub fn get_tile(&self, z: isize, x: isize, y: isize) -> Vec<u8> {
+    pub fn path(z: isize, x: isize, y: isize) -> PathBuf {
+        Path::new(&format!("tiles/{},{},{}.png", z, x, y)).to_path_buf()
+    }
+
+    pub fn generate_tile(&self, z: isize, x: isize, y: isize) {
         info!("generating tile (zoom={z}, x={x}, y={z})");
         let segment = self.renderer.render_segment(x, y);
-        segment
-            .save(format!("tiles/{},{},{}.png", z, x, y))
-            .unwrap();
+        segment.save(Tiler::path(z, x, y)).unwrap();
+    }
 
-        let mut f = File::open(format!("tiles/{},{},{}.png", z, x, y)).unwrap();
+    pub fn update_tile(&self, z: isize, x: isize, y: isize) {
+        // TODO check mtime of region
+        if Tiler::path(z, x, y).exists() {
+            return; // already generated
+        }
+        self.generate_tile(z, x, y)
+    }
+
+    pub fn get_tile(&self, z: isize, x: isize, y: isize) -> Vec<u8> {
+        self.update_tile(z, x, y);
+        let mut f = File::open(Tiler::path(z, x, y)).unwrap();
         let mut buf = Vec::new();
         f.read_to_end(&mut buf).unwrap();
         buf
diff --git a/src/viewer/mod.rs b/src/viewer/mod.rs
index a411c29..f898c30 100644
--- a/src/viewer/mod.rs
+++ b/src/viewer/mod.rs
@@ -18,7 +18,7 @@ pub fn serve_http(dimension: Dimension, bind: SocketAddr) {
                 .and(tiler.clone())
                 .and_then(|z, x, y, tiler: Arc<Tiler>| async move {
                     Ok::<_, Infallible>(warp::reply::with_header(
-                        tiler.get_tile(z, x, y),
+                        tiler.get_tile(z, x, y), // TODO consider using tokio::spawn_blocking so we dont block the event loop
                         "content-type",
                         "image/png",
                     ))