Merge pull request #75 from podusowski/minor-refa

Minor refactor

walkers/src/map.rs

@@ -60,7 +60,7 @@ impl<'a, 'b> Map<'a, 'b> {
     }
 }
 
-/// Projects geographical position into screen pixels, suitable for [`egui::Painter`].
+/// Projects geographical position into pixels on the viewport, suitable for [`egui::Painter`].
 #[derive(Clone)]
 pub struct Projector {
     clip_rect: Rect,
@@ -69,6 +69,7 @@ pub struct Projector {
 }
 
 impl Projector {
+    /// Project `position` into pixels on the viewport.
     pub fn project(&self, position: Position) -> Vec2 {
         // Turn that into a flat, mercator projection.
         let projected_position = position.project(self.memory.zoom.round());

walkers/src/mercator.rs

@@ -35,7 +35,7 @@ impl Position {
 
     /// Project geographical position into a 2D plane using Mercator.
     pub(crate) fn project(&self, zoom: u8) -> Pixels {
-        let (x, y) = mercator_normalized((*self).into());
+        let (x, y) = mercator_normalized(*self);
 
         // Map that into a big bitmap made out of web tiles.
         let number_of_pixels = 2u32.pow(zoom as u32) * TILE_SIZE;
@@ -47,7 +47,7 @@ impl Position {
 
     /// Tile this position is on.
     pub(crate) fn tile_id(&self, zoom: u8) -> TileId {
-        let (x, y) = mercator_normalized((*self).into());
+        let (x, y) = mercator_normalized(*self);
 
         // Map that into a big bitmap made out of web tiles.
         let number_of_tiles = 2u32.pow(zoom as u32);
@@ -58,12 +58,6 @@ impl Position {
     }
 }
 
-impl From<Position> for (f64, f64) {
-    fn from(value: Position) -> Self {
-        (value.lon(), value.lat())
-    }
-}
-
 /// Location projected on the screen or an abstract bitmap.
 pub type Pixels = geo_types::Point;
 
@@ -82,10 +76,10 @@ impl PixelsExt for Pixels {
 /// Size of the tiles used by the services like the OSM.
 pub(crate) const TILE_SIZE: u32 = 256;
 
-fn mercator_normalized((x, y): (f64, f64)) -> (f64, f64) {
+fn mercator_normalized(position: Position) -> (f64, f64) {
     // Project into Mercator (cylindrical map projection).
-    let x = x.to_radians();
-    let y = y.to_radians().tan().asinh();
+    let x = position.lon().to_radians();
+    let y = position.lat().to_radians().tan().asinh();
 
     // Scale both x and y to 0-1 range.
     let x = (1. + (x / PI)) / 2.;