added god rays

app/node_modules/three-good-godrays/README.md

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+# `three-good-godrays`
+
+[![CI](https://github.com/ameobea/three-good-godrays/actions/workflows/cd.yml/badge.svg)](https://github.com/ameobea/three-good-godrays/actions/workflows/ci.yml)
+[![Version](https://badgen.net/npm/v/three-good-godrays?color=green)](https://www.npmjs.com/package/three-good-godrays)
+
+Good godrays effect for three.js using the [pmndrs `postprocessing` library](https://github.com/pmndrs/postprocessing)
+
+Adapted from [original implementation](https://github.com/n8python/goodGodRays) by [@n8python](https://github.com/n8python)
+
+**Demo**: <https://three-good-godrays.ameo.design>
+
+![A screenshot showing the three-good-godrays effect in action within the sponza demo scene. A white sphere in the middle of a terrace with pillars has white godrays emanating from it along with prominent shadows.](https://ameo.link/u/al8.jpg)
+
+## Install
+
+`npm install three-good-godrays`
+
+Or import from unpkg as a module:
+
+```ts
+import { GodraysPass } from 'https://unpkg.com/three-good-godrays@0.7.1/build/three-good-godrays.esm.js';
+```
+
+## Supported Three.JS Version
+
+This library was tested to work with Three.JS versions `>= 0.125.0 <= 0.167.0`.  Although it might work with versions outside that range, support is not guaranteed.
+
+## Usage
+
+```ts
+import { EffectComposer, RenderPass } from 'postprocessing';
+import * as THREE from 'three';
+import { GodraysPass } from 'three-good-godrays';
+
+const { scene, camera, renderer } = initYourScene();
+
+// shadowmaps are needed for this effect
+renderer.shadowMap.enabled = true;
+renderer.shadowMap.type = THREE.PCFSoftShadowMap;
+renderer.shadowMap.autoUpdate = true;
+
+// Make sure to set applicable objects in your scene to cast + receive shadows
+// so that this effect will work
+scene.traverse(obj => {
+  if (obj instanceof THREE.Mesh) {
+    obj.castShadow = true;
+    obj.receiveShadow = true;
+  }
+});
+
+// godrays can be cast from either `PointLight`s or `DirectionalLight`s
+const lightPos = new THREE.Vector3(0, 20, 0);
+const pointLight = new THREE.PointLight(0xffffff, 1, 10000);
+pointLight.castShadow = true;
+pointLight.shadow.mapSize.width = 1024;
+pointLight.shadow.mapSize.height = 1024;
+pointLight.shadow.autoUpdate = true;
+pointLight.shadow.camera.near = 0.1;
+pointLight.shadow.camera.far = 1000;
+pointLight.shadow.camera.updateProjectionMatrix();
+pointLight.position.copy(lightPos);
+scene.add(pointLight);
+
+// set up rendering pipeline and add godrays pass at the end
+const composer = new EffectComposer(renderer, { frameBufferType: THREE.HalfFloatType });
+
+const renderPass = new RenderPass(scene, camera);
+renderPass.renderToScreen = false;
+composer.addPass(renderPass);
+
+// Default values are shown.  You can supply a sparse object or `undefined`.
+const params = {
+  density: 1 / 128,
+  maxDensity: 0.5,
+  edgeStrength: 2,
+  edgeRadius: 2,
+  distanceAttenuation: 2,
+  color: new THREE.Color(0xffffff),
+  raymarchSteps: 60,
+  blur: true,
+  gammaCorrection: true,
+};
+
+const godraysPass = new GodraysPass(pointLight, camera, params);
+// If this is the last pass in your pipeline, set `renderToScreen` to `true`
+godraysPass.renderToScreen = true;
+composer.addPass(godraysPass);
+
+function animate() {
+  requestAnimationFrame(animate);
+  composer.render();
+}
+requestAnimationFrame(animate);
+```
+
+### Gamma Correction
+
+Gamma correction is enabled by this effect by default, matching expectations of sRGB buffers from `postprocessing`. However, you can disable this by setting `gammaCorrection: false` in the configuration object for the pass.
+
+This may be necessary if you use other effect passes after `GodraysPass` that perform their own output encoding. If you see artifacts similar to these:
+
+![Screenshot of artifacts caused by double encoding in a Three.Js pmndrs postprocessing pipeline.  There is a grainy pattern of colorful pixels appearing over an otherwise blank black background.](https://i.ameo.link/bto.png)
+
+Try setting `gammaCorrection: false` on the `GodraysPass` or setting `encodeOutput = false` on any `EffectPass` that is added after the `GodraysPass`.
+
+## Develop + Run Demos Locally
+
+- Clone repo
+- `npm install`
+- `npm run prepublishOnly` to run initial builds
+- `npm install -g serve`
+- Run `node esbuild.mjs` whenever files are chnaged to re-build
+- Run `serve public/demo -p 5001` and visit http://localhost:5001 in your browser