Reimplement one-hit KO effect

src/pipelines/invert.ts

@@ -0,0 +1,27 @@
+import { Game } from "phaser";
+
+const fragShader = `
+precision mediump float;
+
+uniform sampler2D uMainSampler;
+
+varying vec2 outTexCoord;
+
+void main()
+{
+    gl_FragColor = 1.0 - texture2D(uMainSampler, outTexCoord);
+}
+`;
+
+export default class InvertPostFX extends Phaser.Renderer.WebGL.Pipelines.PostFXPipeline {
+    constructor (game: Game) {
+        super({
+            game,
+            name: 'InvertPostFX',
+            fragShader,
+            uniforms: [
+                'uMainSampler'
+            ]
+        } as Phaser.Types.Renderer.WebGL.WebGLPipelineConfig);
+    }
+}