fix seek when paused

wasm-module/src/lib.rs

@@ -122,6 +122,11 @@ impl PlaybackHead{
 		self.head.set_paused(time,paused);
 	}
 	#[wasm_bindgen]
+	pub fn get_scale(&mut self)->f64{
+		let scale=self.head.get_scale();
+		scale.num() as f64/scale.den() as f64
+	}
+	#[wasm_bindgen]
 	pub fn set_scale(&mut self,time:f64,scale:f64){
 		let time=time::from_float(time).unwrap();
 		self.head.set_scale(time,scale.try_into().unwrap());