From 61aa9753af614ae65ad9b58528a28e6b180e3b69 Mon Sep 17 00:00:00 2001
From: Haowei Wen <yushijinhun@gmail.com>
Date: Sat, 10 Oct 2020 10:22:17 +0800
Subject: [PATCH] Add PlayerObject.backEquipment property

---
 README.md                      |  6 +++++-
 examples/index.html            | 22 +++++++++++++++++++++-
 examples/offscreen-render.html | 14 +++++++++-----
 src/model.ts                   | 17 +++++++++++++++++
 src/viewer.ts                  | 31 ++++++++++++++++---------------
 5 files changed, 68 insertions(+), 22 deletions(-)

diff --git a/README.md b/README.md
index 09176db..a467084 100644
--- a/README.md
+++ b/README.md
@@ -12,6 +12,7 @@ Three.js powered Minecraft skin viewer.
 * 1.8 Skins
 * HD Skins
 * Capes
+* Elytras
 * Slim Arms
   * Automatic model detection (Slim / Default)
 
@@ -37,7 +38,10 @@ Three.js powered Minecraft skin viewer.
 	// Load a cape
 	skinViewer.loadCape("img/cape.png");
 
-	// Unload(hide) the cape
+	// Load a elytra (from a cape texture)
+	skinViewer.loadCape("img/cape.png", { backEquipment: "elytra" });
+
+	// Unload(hide) the cape / elytra
 	skinViewer.loadCape(null);
 
 	// Control objects with your mouse!
diff --git a/examples/index.html b/examples/index.html
index dcd8b41..0e0e12e 100644
--- a/examples/index.html
+++ b/examples/index.html
@@ -182,6 +182,13 @@
 					</tr>
 				</tbody>
 			</table>
+			<div>
+				<h2>Back Equipment</h2>
+				<div class="control">
+					<label><input type="radio" id="back_equipment_cape" name="back_equipment" value="cape" checked> Cape</label>
+					<label><input type="radio" id="back_equipment_elytra" name="back_equipment" value="elytra"> Elytra</label>
+				</div>
+			</div>
 		</div>
 
 		<div class="control-section">
@@ -284,7 +291,8 @@
 				skinViewer.loadCape(null);
 				input.setCustomValidity("");
 			} else {
-				skinViewer.loadCape(url)
+				const selectedBackEquipment = document.querySelector('input[type="radio"][name="back_equipment"]:checked');
+				skinViewer.loadCape(url, { backEquipment: selectedBackEquipment.value })
 					.then(() => input.setCustomValidity(""))
 					.catch(e => {
 						input.setCustomValidity("Image can't be loaded.");
@@ -363,6 +371,18 @@
 			document.getElementById("skin_url").addEventListener("change", () => reloadSkin());
 			document.getElementById("skin_model").addEventListener("change", () => reloadSkin());
 			document.getElementById("cape_url").addEventListener("change", () => reloadCape());
+
+			for (const el of document.querySelectorAll('input[type="radio"][name="back_equipment"]')) {
+				el.addEventListener("change", e => {
+					if (skinViewer.playerObject.backEquipment === null) {
+						// cape texture hasn't been loaded yet
+						// this option will be processed on texture loading
+					} else {
+						skinViewer.playerObject.backEquipment = e.target.value;
+					}
+				});
+			}
+
 			document.getElementById("reset_all").addEventListener("click", () => {
 				skinViewer.dispose();
 				orbitControl.dispose();
diff --git a/examples/offscreen-render.html b/examples/offscreen-render.html
index 5ebbfb2..662c209 100644
--- a/examples/offscreen-render.html
+++ b/examples/offscreen-render.html
@@ -12,7 +12,7 @@
     <div id="rendered_imgs"></div>
     <script src="../bundles/skinview3d.bundle.js"></script>
     <script>
-        const textures = [
+        const configurations = [
             {
                 skin: "img/1_8_texturemap_redux.png",
                 cape: null
@@ -23,11 +23,12 @@
             },
             {
                 skin: "img/haka.png",
-                cape: null
+                cape: "img/mojang_cape.png"
             },
             {
                 skin: "img/hatsune_miku.png",
-                cape: "img/mojang_cape.png"
+                cape: "img/mojang_cape.png",
+                backEquipment: "elytra"
             },
             {
                 skin: "img/ironman_hd.png",
@@ -54,8 +55,11 @@
             skinViewer.camera.position.y = 22.0;
             skinViewer.camera.position.z = 42.0;
 
-            for (const { skin, cape } of textures) {
-                await Promise.all([skinViewer.loadSkin(skin), skinViewer.loadCape(cape)]);
+            for (const config of configurations) {
+                await Promise.all([
+                    skinViewer.loadSkin(config.skin),
+                    skinViewer.loadCape(config.cape, { backEquipment: config.backEquipment })
+                ]);
                 skinViewer.render();
                 const image = skinViewer.canvas.toDataURL();
 
diff --git a/src/model.ts b/src/model.ts
index 9f52a09..a2fe87b 100644
--- a/src/model.ts
+++ b/src/model.ts
@@ -343,6 +343,8 @@ export class ElytraObject extends Group {
 	}
 }
 
+export type BackEquipment = "cape" | "elytra";
+
 export class PlayerObject extends Group {
 
 	readonly skin: SkinObject;
@@ -369,4 +371,19 @@ export class PlayerObject extends Group {
 		this.elytra.visible = false;
 		this.add(this.elytra);
 	}
+
+	get backEquipment(): BackEquipment | null {
+		if (this.cape.visible) {
+			return "cape";
+		} else if (this.elytra.visible) {
+			return "elytra";
+		} else {
+			return null;
+		}
+	}
+
+	set backEquipment(value: BackEquipment | null) {
+		this.cape.visible = value === "cape";
+		this.elytra.visible = value === "elytra";
+	}
 }
diff --git a/src/viewer.ts b/src/viewer.ts
index 996f785..a8471d8 100644
--- a/src/viewer.ts
+++ b/src/viewer.ts
@@ -1,7 +1,7 @@
 import { applyMixins, CapeContainer, ModelType, SkinContainer, RemoteImage, TextureSource } from "skinview-utils";
 import { NearestFilter, PerspectiveCamera, Scene, Texture, Vector2, WebGLRenderer } from "three";
 import { RootAnimation } from "./animation.js";
-import { PlayerObject } from "./model.js";
+import { BackEquipment, PlayerObject } from "./model.js";
 
 export interface LoadOptions {
 	/**
@@ -10,6 +10,14 @@ export interface LoadOptions {
 	makeVisible?: boolean;
 }
 
+export interface CapeLoadOptions extends LoadOptions {
+	/**
+	 * The equipment (cape or elytra) to show, defaults to "cape".
+	 * If makeVisible is set to false, this option will have no effect.
+	 */
+	backEquipment?: BackEquipment;
+}
+
 export interface SkinViewerOptions {
 	width?: number;
 	height?: number;
@@ -40,13 +48,6 @@ export interface SkinViewerOptions {
 	renderPaused?: boolean;
 }
 
-function toMakeVisible(options?: LoadOptions): boolean {
-	if (options && options.makeVisible === false) {
-		return false;
-	}
-	return true;
-}
-
 class SkinViewer {
 	readonly canvas: HTMLCanvasElement;
 	readonly scene: Scene;
@@ -118,18 +119,18 @@ class SkinViewer {
 		}
 	}
 
-	protected skinLoaded(model: ModelType, options?: LoadOptions): void {
+	protected skinLoaded(model: ModelType, options: LoadOptions = {}): void {
 		this.skinTexture.needsUpdate = true;
 		this.playerObject.skin.modelType = model;
-		if (toMakeVisible(options)) {
+		if (options.makeVisible !== false) {
 			this.playerObject.skin.visible = true;
 		}
 	}
 
-	protected capeLoaded(options?: LoadOptions): void {
+	protected capeLoaded(options: CapeLoadOptions = {}): void {
 		this.capeTexture.needsUpdate = true;
-		if (toMakeVisible(options)) {
-			this.playerObject.cape.visible = true;
+		if (options.makeVisible !== false) {
+			this.playerObject.backEquipment = options.backEquipment === undefined ? "cape" : options.backEquipment;
 		}
 	}
 
@@ -138,7 +139,7 @@ class SkinViewer {
 	}
 
 	protected resetCape(): void {
-		this.playerObject.cape.visible = false;
+		this.playerObject.backEquipment = null;
 	}
 
 	private draw(): void {
@@ -208,6 +209,6 @@ class SkinViewer {
 		this.setSize(this.width, newHeight);
 	}
 }
-interface SkinViewer extends SkinContainer<LoadOptions>, CapeContainer<LoadOptions> { }
+interface SkinViewer extends SkinContainer<LoadOptions>, CapeContainer<CapeLoadOptions> { }
 applyMixins(SkinViewer, [SkinContainer, CapeContainer]);
 export { SkinViewer };