convert classes to es6

(cherry picked from commit e7615d49a4071fe5b5f192884f142c9f3385211a)

src/js/net/minecraft/client/render/isometric/IsometricRenderer.js

@@ -1,4 +1,8 @@
-window.IsometricRenderer = class {
+import TextCoord from "./TextCoord.js";
+import Point from "./Point.js";
+import Triangle from "./Triangle.js";
+
+export default class IsometricRenderer {
 
     // http://jsfiddle.net/xzL58dha/3/
 

src/js/net/minecraft/client/render/isometric/Point.js

@@ -1,4 +1,4 @@
-window.Point = class {
+export default class Point {
     constructor(x, y) {
         this.x = x ? x : 0;
         this.y = y ? y : 0;

src/js/net/minecraft/client/render/isometric/TextCoord.js

@@ -1,4 +1,4 @@
-window.TextCoord = class {
+export default class TextCoord {
     constructor(u, v) {
         this.u = u ? u : 0;
         this.v = v ? v : 0;

src/js/net/minecraft/client/render/isometric/Triangle.js

@@ -1,4 +1,4 @@
-window.Triangle = class {
+export default class Triangle {
     constructor(p0, p1, p2, t0, t1, t2) {
         this.p0 = p0;
         this.p1 = p1;