three.js ~ example ~ Mr.doob
2012-01-05 ~
by Atrahasis
HTML
<script src="http://cdnjs.cloudflare.com/ajax/libs/three.js/r67/three.min.js"></script>JavaScript
var atmosphere, c, camera, diffuse, diffuseNight, f, fragmentGround, fragmentSky, g, ground, maxAnisotropy, radius, render, renderer, scene, sky, uniforms, vertexGround, vertexSky, h;
scene = new THREE.Scene();
camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 0.1, 1000);
camera.position.z = 250;
renderer = new THREE.WebGLRenderer();
renderer.setSize(window.innerWidth, window.innerHeight);
renderer.setClearColorHex(0x000000, 1);
document.body.appendChild(renderer.domElement);
vertexSky = "//\n// Atmospheric scattering vertex shader\n//\n// Author: Sean O'Neil\n//\n// Copyright (c) 2004 Sean O'Neil\n//\n\nuniform vec3 v3LightPosition; // The direction vector to the light source\nuniform vec3 v3InvWavelength; // 1 / pow(wavelength, 4) for the red, green, and blue channels\nuniform float fCameraHeight; // The camera's current height\nuniform float fCameraHeight2; // fCameraHeight^2\nuniform float fOuterRadius; // The outer (atmosphere) radius\nuniform float fOuterRadius2; // fOuterRadius^2\nuniform float fInnerRadius; // The inner (planetary) radius\nuniform float fInnerRadius2; // fInnerRadius^2\nuniform float fKrESun; // Kr * ESun\nuniform float fKmESun; // Km * ESun\nuniform float fKr4PI; // Kr * 4 * PI\nuniform float fKm4PI; // Km * 4 * PI\nuniform float fScale; // 1 / (fOuterRadius - fInnerRadius)\nuniform float fScaleDepth; // The scale depth (i.e. the altitude at which the atmosphere's average density is found)\nuniform float fScaleOverScaleDepth; // fScale / fScaleDepth\n\nconst int nSamples = 3;\nconst float fSamples = 3.0;\n\nvarying vec3 v3Direction;\nvarying vec3 c0;\nvarying vec3 c1;\n\n\nfloat scale(float fCos)\n{\n float x = 1.0 - fCos;\n return fScaleDepth * exp(-0.00287 + x*(0.459 + x*(3.83 + x*(-6.80 + x*5.25))));\n}\n\nvoid main(void)\n{\n // Get the ray from the camera to the vertex and its length (which is the far point of the ray passing through the atmosphere)\n vec3 v3Ray = position -...