Don't load sounds for events that are too far to be heard

#742

doc/CHANGES.txt

@@ -24,6 +24,7 @@ Changelog
 - added support for animated entity overlay effects
 - added transformation effect to vampires
 - cleaned up bestiary window layout
+- performance optimization: sound events too far away to be heard are not loaded
 
 
 1.47

src/js/stendhal/entity/User.ts

@@ -136,6 +136,27 @@ export class User extends Player {
 				&& (Math.abs(this["y"] - entity["y"]) < hearingRange));
 	}
 
+	/**
+	 * Checks if player is within range to hear a sound event.
+	 *
+	 * @param {number} radius
+	 *   Distance at which sound can be heard.
+	 * @param {Entity} entity
+	 *   Entity emitting sound event.
+	 * @returns {boolean}
+	 *   `true` if sound should be loaded (when event radius is more than -1 & user position is within
+	 *   radial distance from event origin).
+	 */
+	isInSoundRange(radius: number, entity: Entity): boolean {
+		if (entity === this) {
+			return true;
+		}
+		if (radius < 0) {
+			return false;
+		}
+		return Math.abs(this["x"] - entity["x"]) + Math.abs(this["y"] - entity["y"]) <= radius;
+	}
+
 	/**
 	 * Actions when player leaves a zone.
 	 */

src/js/stendhal/event/SoundEvent.ts

@@ -15,6 +15,7 @@ import { RPEvent } from "./RPEvent";
 import { SoundID } from "../data/sound/SoundID";
 import { SoundManager } from "../data/sound/SoundManager";
 
+declare var marauroa: any;
 declare var stendhal: any;
 
 
@@ -28,10 +29,18 @@ export class SoundEvent extends RPEvent {
 
 
 	execute(entity: any) {
+		if (!marauroa.me) {
+			return;
+		}
 		let radius = SoundManager.DEFAULT_RADIUS;
 		if (typeof(this["radius"]) === "number") {
 			radius = this["radius"];
 		}
+		if (!marauroa.me.isInSoundRange(radius, entity)) {
+			// too far away to hear so don't load
+			return;
+		}
+
 		let volume = 1;
 		// Adjust by the server specified volume, if any
 		if (this.hasOwnProperty("volume")) {