refactoring

src/lib.rs

@@ -7,12 +7,6 @@ static ALLOC: wee_alloc::WeeAlloc = wee_alloc::WeeAlloc::INIT;
 
 pub type DrawResult<T> = Result<T, Box<dyn std::error::Error>>;
 
-#[wasm_bindgen]
-pub struct Chart {
-    convert: Box<dyn Fn((i32, i32)) -> Option<(f32, f32)>>,
-    area: f32,
-}
-
 /// Result of screen to chart coordinates conversion.
 #[wasm_bindgen]
 pub struct Point {
@@ -20,6 +14,17 @@ pub struct Point {
     pub y: f32,
 }
 
+#[wasm_bindgen]
+impl Point {
+    pub fn new(x: f32, y: f32) -> Self { Self { x, y } }
+}
+
+#[wasm_bindgen]
+pub struct Chart {
+    convert: Box<dyn Fn((i32, i32)) -> Option<(f32, f32)>>,
+    area: f32,
+}
+
 #[wasm_bindgen]
 impl Chart {
     pub fn draw(
@@ -48,6 +53,6 @@ impl Chart {
     pub fn get_area(&self) -> f32 { return self.area; }
 
     pub fn coord(&self, x: i32, y: i32) -> Option<Point> {
-        (self.convert)((x, y)).map(|(x, y)| Point { x, y })
+        (self.convert)((x, y)).map(|(x, y)| Point::new(x, y))
     }
 }