Qt 5.8 | Qt Canvas 3D | Planets Example | planets.js Example File

Qt 5.8.0 Reference Documentation

# planets.js Example File

threejs/planets/planets.js

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      Qt.include("three.js")
      Qt.include("threex.planets.js")

      var SUN = 0;
      var MERCURY = 1;
      var VENUS = 2;
      var EARTH = 3;
      var MARS = 4;
      var JUPITER = 5;
      var SATURN = 6;
      var URANUS = 7;
      var NEPTUNE = 8;
      var NUM_SELECTABLE_PLANETS = 9;
      var MOON = 9;
      var SOLAR_SYSTEM = 100;

      var camera, scene, renderer;
      var planetCanvas, mouse, raycaster;

      var daysPerFrame;
      var daysPerFrameScale;
      var planetScale;
      var cameraDistance;

      var objects = []; // Planet objects
      var hitObjects = []; // Planet hit detection objects
      var planets = []; // Planet data info

      var commonGeometry;
      var hitGeometry;
      var solarDistance = 2600000;
      var saturnOuterRadius = 120.700;
      var uranusOuterRadius = 40;

      var qmlView;

      var oldFocusedPlanetPosition;
      var oldCameraPosition;
      var defaultCameraPosition;

      var y = 2000;
      var m = 1;
      var D = 1;
      // Time scale formula based on http://www.stjarnhimlen.se/comp/ppcomp.html
      var startD = 367 * y - 7 * (y + (m + 9) / 12) / 4 + 275 * m / 9 + D - 730530;
      var oldTimeD = startD;
      var currTimeD = startD;

      var auScale = 149597.870700; // AU in thousands of kilometers

      var focusedScaling = false;
      var focusedMinimumScale = 20;
      var actualScale;

      function initializeGL(canvas, eventSource, mainView) {

          planetCanvas = canvas;
          qmlView = mainView;

          camera = new THREE.PerspectiveCamera(45, canvas.width / canvas.height, 2500000, 20000000);
          defaultCameraPosition = new THREE.Vector3(solarDistance, solarDistance, solarDistance);
          camera.position.set(defaultCameraPosition.x, defaultCameraPosition.y, defaultCameraPosition.z);

          scene = new THREE.Scene();

          var starSphere = THREEx.Planets.createStarfield(8500000);
          scene.add(starSphere);

          var light = new THREE.PointLight(0x777777, 2);
          light.position.set(0, 0, 0);
          scene.add(light);

          scene.add(new THREE.AmbientLight(0x111111));

          loadPlanetData();
          createPlanets();
          setScale(1200);

          camera.lookAt(objects[0].position); // look at the Sun

          raycaster = new THREE.Raycaster();
          mouse = new THREE.Vector2();

          renderer = new THREE.Canvas3DRenderer(
                      { canvas: canvas, antialias: true, devicePixelRatio: canvas.devicePixelRatio });

          renderer.setPixelRatio(canvas.devicePixelRatio);
          renderer.setSize(canvas.width, canvas.height);
          eventSource.mouseDown.connect(onDocumentMouseDown);
      }

      function loadPlanetData() {

          // Planet Data
          // radius - planet radius in millions of meters
          // tilt - planet axis angle
          // N1 N2 - longitude of the ascending node
          // i1 i2 - inclination to the ecliptic (plane of the Earth's orbit)
          // w1 w2 - argument of perihelion
          // a1 a2 - semi-major axis, or mean distance from Sun
          // e1 e2 - eccentricity (0=circle, 0-1=ellipse, 1=parabola)
          // M1 M2 - mean anomaly (0 at perihelion; increases uniformly with time)
          // period - sidereal rotation period
          // centerOfOrbit - the planet in the center of the orbit
          // (orbital elements based on http://www.stjarnhimlen.se/comp/ppcomp.html)

          var sun = { radius: 694.439, tilt: 63.87, period: 25.05 };
          planets.push(sun);
          var mercury = {
              radius: 2.433722, tilt: 0.04, N1: 48.3313, N2: 0.0000324587,
              i1: 7.0047, i2: 0.0000000500, w1: 29.1241, w2: 0.0000101444,
              a1: 0.387098, a2: 0, e1: 0.205635, e2: 0.000000000559,
              M1: 168.6562, M2: 4.0923344368, period: 58.646,
              centerOfOrbit: SUN
          };
          planets.push(mercury);
          var venus = {
              radius: 6.046079, tilt: 177.36, N1: 76.6799, N2: 0.0000246590,
              i1: 3.3946, i2: 0.0000000275, w1: 54.8910, w2: 0.0000138374,
              a1: 0.723330, a2: 0, e1: 0.006773, e2: -0.000000001302,
              M1: 48.0052, M2: 1.6021302244, period: 243.0185,
              centerOfOrbit: SUN
          };
          planets.push(venus);
          var earth = {
              radius: 6.371, tilt: 25.44, N1: 174.873, N2: 0,
              i1: 0.00005, i2: 0, w1: 102.94719, w2: 0,
              a1: 1, a2: 0, e1: 0.01671022, e2: 0,
              M1: 357.529, M2: 0.985608, period: 0.997,
              centerOfOrbit: SUN
          };
          planets.push(earth);
          var mars = {
              radius: 3.389372, tilt: 25.19, N1: 49.5574, N2: 0.0000211081,
              i1: 1.8497, i2: -0.0000000178, w1: 286.5016, w2: 0.0000292961,
              a1: 1.523688, a2: 0, e1: 0.093405, e2: 0.000000002516,
              M1: 18.6021, M2: 0.5240207766, period: 1.025957,
              centerOfOrbit: SUN
          };
          planets.push(mars);
          var jupiter = {
              radius: 71.41254, tilt: 3.13, N1: 100.4542, N2: 0.0000276854,
              i1: 1.3030, i2: -0.0000001557, w1: 273.8777, w2: 0.0000164505,
              a1: 5.20256, a2: 0, e1: 0.048498, e2: 0.000000004469,
              M1: 19.8950, M2: 0.0830853001, period: 0.4135,
              centerOfOrbit: SUN
          };
          planets.push(jupiter);
          var saturn = {
              radius: 60.19958, tilt: 26.73, N1: 113.6634, N2: 0.0000238980,
              i1: 2.4886, i2: -0.0000001081, w1: 339.3939, w2: 0.0000297661,
              a1: 9.55475, a2: 0, e1: 0.055546, e2: -0.000000009499,
              M1: 316.9670, M2: 0.0334442282, period: 0.4395,
              centerOfOrbit: SUN
          };
          planets.push(saturn);
          var uranus = {
              radius: 25.5286, tilt: 97.77, N1: 74.0005, N2: 0.000013978,
              i1: 0.7733, i2: 0.000000019, w1: 96.6612, w2: 0.000030565,
              a1: 19.18171, a2: -0.0000000155, e1: 0.047318, e2: 0.00000000745,
              M1: 142.5905, M2: 0.011725806, period: 0.71833,
              centerOfOrbit: SUN
          };
          planets.push(uranus);
          var neptune = {
              radius: 24.73859, tilt: 28.32, N1: 131.7806, N2: 0.000030173,
              i1: 1.7700, i2: -0.000000255, w1: 272.8461, w2: 0.000006027,
              a1: 30.05826, a2: 0.00000003313, e1: 0.008606, e2: 0.00000000215,
              M1: 260.2471, M2: 0.005995147, period: 0.6713,
              centerOfOrbit: SUN
          };
          planets.push(neptune);
          var moon = {
              radius: 1.5424, tilt: 28.32, N1: 125.1228, N2: -0.0529538083,
              i1: 5.1454, i2: 0, w1: 318.0634, w2: 0.1643573223,
              a1: 0.273, a2: 0, e1: 0.054900, e2: 0,
              M1: 115.3654, M2: 13.0649929509, period: 27.321582,
              centerOfOrbit: EARTH
          };
          planets.push(moon);

      }

      function createPlanets() {

          objects = [];

          commonGeometry = new THREE.BufferGeometry().fromGeometry(new THREE.SphereGeometry(1, 64, 64));
          hitGeometry = new THREE.BufferGeometry().fromGeometry(new THREE.SphereGeometry(1, 8, 8));

          var ringSegments = 70;
          var mesh, innerRadius, outerRadius, ring;

          for (var i = 0; i < planets.length; i ++) {
              switch (i) {
              case SUN:
                  mesh = createSun(planets[i]["radius"]);
                  mesh.position.set(0, 0, 0);
                  break;
              case MERCURY:
                  mesh = createPlanet(planets[i]["radius"], 0.005, 'images/mercurymap.jpg',
                                      'images/mercurybump.jpg');
                  break;
              case VENUS:
                  mesh = createPlanet(planets[i]["radius"], 0.005, 'images/venusmap.jpg',
                                      'images/venusbump.jpg');
                  break;
              case EARTH:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/earthmap1k.jpg',
                                      'images/earthbump1k.jpg', 'images/earthspec1k.jpg');
                  createEarthCloud(mesh);
                  break;
              case MARS:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/marsmap1k.jpg',
                                      'images/marsbump1k.jpg');
                  break;
              case JUPITER:
                  mesh = createPlanet(planets[i]["radius"], 0.02, 'images/jupitermap.jpg',
                                      'images/jupitermap.jpg');
                  break;
              case SATURN:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/saturnmap.jpg',
                                      'images/saturnmap.jpg');
                  innerRadius = (planets[i]["radius"] + 6.630) / planets[i]["radius"];
                  outerRadius = (planets[i]["radius"] + saturnOuterRadius) / planets[i]["radius"];
                  ring = createRing(innerRadius, outerRadius, ringSegments,
                                        'qrc:images/saturnringcolortrans.png');
                  ring.receiveShadow = true;
                  ring.castShadow = true;
                  mesh.add(ring);
                  break;
              case URANUS:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/uranusmap.jpg',
                                      'images/uranusmap.jpg');
                  innerRadius = (planets[i]["radius"] + 2) / planets[i]["radius"];
                  outerRadius = (planets[i]["radius"] + uranusOuterRadius) / planets[i]["radius"];
                  ring = createRing(innerRadius, outerRadius, ringSegments,
                                        'qrc:images/uranusringcolortrans.png');
                  ring.receiveShadow = true;
                  ring.castShadow = true;
                  mesh.add(ring);
                  break;
              case NEPTUNE:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/neptunemap.jpg',
                                      'images/neptunemap.jpg');
                  break;
              case MOON:
                  mesh = createPlanet(planets[i]["radius"], 0.05, 'images/moonmap1k.jpg',
                                      'images/moonbump1k.jpg');
                  break;
              }

              objects.push(mesh);
              scene.add(mesh);

              // Create separate meshes for click detection
              var hitMesh = new THREE.Mesh(hitGeometry);
              hitMesh.visible = false;
              hitObjects.push(hitMesh);
              scene.add(hitMesh);
          }

      }

      function createSun(radius) {

          var textureLoader = new THREE.TextureLoader();
          var texture = textureLoader.load('images/sunmap.jpg');
          var material = new THREE.MeshBasicMaterial({ map: texture });
          var mesh = new THREE.Mesh(commonGeometry, material);
          mesh.scale.set(radius, radius, radius);

          mesh.receiveShadow = false;
          mesh.castShadow = false;

          return mesh;
      }

      function createPlanet(radius, bumpMapScale, mapTexture, bumpTexture, specularTexture) {

          var textureLoader = new THREE.TextureLoader();
          var material = new THREE.MeshPhongMaterial({
                                                         map: textureLoader.load(mapTexture),
                                                         bumpMap: textureLoader.load(bumpTexture),
                                                         bumpScale: bumpMapScale
                                                     });

          if (specularTexture) {
              material.specularMap = textureLoader.load(specularTexture);
              material.specular = new THREE.Color('grey');
              material.shininess = 50.0;
          } else {
              material.shininess = 1.0;
          }

          var mesh = new THREE.Mesh(commonGeometry, material);
          mesh.scale.set(radius, radius, radius);

          return mesh;

      }

      function createEarthCloud(earthMesh) {

          var textureLoader = new THREE.TextureLoader();
          var material = new THREE.MeshPhongMaterial({
                                                         map: textureLoader.load('qrc:images/earthcloudmapcolortrans.png'),
                                                         side: THREE.BackSide,
                                                         transparent: true,
                                                         opacity: 0.8
                                                     });
          var mesh = new THREE.Mesh(commonGeometry, material);

          var material2 = new THREE.MeshPhongMaterial({
                                                         map: textureLoader.load('qrc:images/earthcloudmapcolortrans.png'),
                                                         side: THREE.FrontSide,
                                                         transparent: true,
                                                         opacity: 0.8
                                                     });
          var mesh2 = new THREE.Mesh(commonGeometry, material2);

          mesh.scale.set(1.02, 1.02, 1.02);
          earthMesh.add(mesh);
          mesh2.scale.set(1.02, 1.02, 1.02);
          earthMesh.add(mesh2);
      }

      function createRing(radius, width, height, texture) {

          var textureLoader = new THREE.TextureLoader();
          var geometry = new THREE.BufferGeometry().fromGeometry(
                      new THREEx.Planets._RingGeometry(radius, width, height));

          var material = new THREE.MeshPhongMaterial({
                                                         map: textureLoader.load(texture),
                                                         side: THREE.DoubleSide,
                                                         transparent: true,
                                                         opacity: 0.8
                                                     });
          material.map.minFilter = THREE.NearestFilter;
          var mesh = new THREE.Mesh(geometry, material);
          mesh.lookAt(new THREE.Vector3(0, 90, 0));

          return mesh;

      }

      function createStarfield(radius) {

          var textureLoader = new THREE.TextureLoader();
          var texture = textureLoader.load('images/galaxy_starfield.png')
          var material = new THREE.MeshBasicMaterial({
                                                         map: texture,
                                                         side: THREE.BackSide
                                                     })
          var geometry = new THREE.BufferGeometry().fromGeometry(new THREE.SphereGeometry(radius, 32, 32));
          var mesh = new THREE.Mesh(geometry, material)

          return mesh

      }

      function onResizeGL(canvas) {

          if (camera === undefined) return;

          camera.aspect = canvas.width / canvas.height;
          camera.updateProjectionMatrix();
          renderer.setPixelRatio(canvas.devicePixelRatio);
          renderer.setSize(canvas.width, canvas.height);

      }

      function onSpeedChanged(value) {

          daysPerFrameScale = value;

      }

      function setScale(value, focused) {

          // Save actual scale in focus mode
          if (!focused)
              actualScale = value;

          // Limit minimum scaling in focus mode to avoid jitter caused by rounding errors
          if (value <= focusedMinimumScale && (focusedScaling || focused)) {
              planetScale = focusedMinimumScale;
          } else {
              planetScale = actualScale;
          }

          for (var i = 0; i < objects.length; i++) {
              var object = objects[i];
              // first reset scale
              var radius = planets[i]["radius"];
              object.scale.set(radius, radius, radius);
              if (i === SUN) {
                  object.scale.multiplyScalar(planetScale / 100);
              } else {
                  object.scale.multiplyScalar(planetScale);
              }
              hitObjects[i].scale.set(object.scale.x, object.scale.y, object.scale.z);
          }

      }

      function prepareFocusedPlanetAnimation() {

          oldCameraPosition = camera.position.clone();

          var planet = SUN;
          if (qmlView.oldPlanet !== SOLAR_SYSTEM)
              planet = qmlView.oldPlanet;
          oldFocusedPlanetPosition = objects[planet].position.clone();
          qmlView.oldPlanet = qmlView.focusedPlanet;

          if (qmlView.focusedPlanet !== SOLAR_SYSTEM && actualScale <= focusedMinimumScale) {
              // Limit minimum scaling in focus mode to avoid jitter caused by rounding errors
              planetScale = focusedMinimumScale;
              setScale(focusedMinimumScale, true);
              focusedScaling = true;
          } else if (focusedScaling === true) {
              // Restore normal scaling
              focusedScaling = false;
              setScale(actualScale);
          }

          calculateLookAtOffset();
          calculateCameraOffset();

      }

      function setCameraDistance(distance) {

          cameraDistance = distance;

      }

      function calculateLookAtOffset() {

          var offset = oldFocusedPlanetPosition.clone();

          var planet = 0;
          if (qmlView.focusedPlanet !== SOLAR_SYSTEM)
              planet = qmlView.oldPlanet;

          var focusedPlanetPosition = objects[planet].position.clone();
          offset.sub(focusedPlanetPosition);

          qmlView.xLookAtOffset = offset.x;
          qmlView.yLookAtOffset = offset.y;
          qmlView.zLookAtOffset = offset.z;

      }

      function calculateCameraOffset() {

          var offset = oldCameraPosition.clone();

          var planet = 0;
          if (qmlView.focusedPlanet !== SOLAR_SYSTEM)
              planet = qmlView.focusedPlanet;

          var newCameraPosition = getNewCameraPosition(getOuterRadius(planet));

          if (qmlView.focusedPlanet !== SUN)
              offset.sub(newCameraPosition);

          if (qmlView.focusedPlanet === SUN && qmlView.oldPlanet === SOLAR_SYSTEM) {
              qmlView.xCameraOffset = Math.abs(offset.x);
              qmlView.yCameraOffset = Math.abs(offset.y);
              qmlView.zCameraOffset = Math.abs(offset.z);
          } else { // from a planet to another
              qmlView.xCameraOffset = offset.x;
              qmlView.yCameraOffset = offset.y;
              qmlView.zCameraOffset = offset.z;
          }

      }

      function getNewCameraPosition( radius ) {

          var position;
          if (qmlView.focusedPlanet === SOLAR_SYSTEM) {
              position = defaultCameraPosition.clone();
              position.multiplyScalar(cameraDistance);
          } else if (qmlView.focusedPlanet === SUN) {
              position = new THREE.Vector3(radius * planetScale * 2,
                                           radius * planetScale * 2,
                                           radius * planetScale * 2);
              position.multiplyScalar(cameraDistance);

          } else {
              var vec1 = objects[qmlView.focusedPlanet].position.clone();
              var vec2 = new THREE.Vector3(0, 1, 0);
              vec1.normalize();
              vec2.cross(vec1);
              vec2.multiplyScalar(radius * planetScale * cameraDistance * 4);
              vec2.add(objects[qmlView.focusedPlanet].position);
              vec1.set(0, radius * planetScale, 0);
              vec2.add(vec1);
              position = vec2;
          }
          return position;
      }

      function onDocumentMouseDown(x, y) {

          // Mouse selection for planets and Solar system, not for the Moon.
          // Intersection tests are done against a set of cruder hit objects instead of
          // actual planet meshes, as checking a lot of faces can be slow.
          mouse.set((x / planetCanvas.width) * 2 - 1, - (y / planetCanvas.height ) * 2 + 1);

          raycaster.setFromCamera(mouse, camera);

          var intersects = [];
          var i = 0;
          var objectCount = hitObjects.length - 1; // -1 excludes the moon, which is the last object
          while (i < objectCount) {
              // Update hitObject position
              var objectPos = objects[i].position;
              var hitObject = hitObjects[i];
              hitObject.position.set(objectPos.x, objectPos.y, objectPos.z);
              hitObject.updateMatrixWorld();

              hitObject.raycast( raycaster, intersects );

              i++;
          }
          intersects.sort( raycaster.ascSort );

          var selectedPlanet;

          if (intersects.length > 0) {
              var intersect = intersects[0];

              i = 0;
              while (i < objectCount) {
                  if (intersect.object === hitObjects[i]) {
                      selectedPlanet = i;
                      break;
                  }
                  i++;
              }
              if (selectedPlanet < NUM_SELECTABLE_PLANETS) {
                  qmlView.focusedPlanet = selectedPlanet;
                  // Limit minimum scaling in focus mode to avoid jitter caused by rounding errors
                  if (actualScale <= focusedMinimumScale) {
                      planetScale = focusedMinimumScale;
                      setScale(focusedMinimumScale, true);
                  }
                  focusedScaling = true;
              }
          } else {
              qmlView.focusedPlanet = SOLAR_SYSTEM;
              // Restore normal scaling
              if (focusedScaling === true) {
                  focusedScaling = false;
                  setScale(actualScale);
              }
          }

      }

      function paintGL(canvas) {

          if (qmlView.focusedPlanet === SOLAR_SYSTEM)
              daysPerFrame = daysPerFrameScale * 10;
          else
              daysPerFrame = daysPerFrameScale * planets[qmlView.focusedPlanet]["period"] / 100;

          // Advance the time in days
          oldTimeD = currTimeD;
          currTimeD = currTimeD + daysPerFrame;
          var deltaTimeD = currTimeD - oldTimeD;

          // Position the planets orbiting the sun
          for (var i = 1; i < objects.length; i ++) {
              var object = objects[i];
              var planet = planets[i];

              // Bumpmaps of mercury, venus, jupiter and moon need special handling
              if (i == MERCURY || i == VENUS || i == JUPITER || i == MOON)
                  object.material.bumpScale = 0.03 * planetScale;
              else
                  object.material.bumpScale = 0.3 * planetScale;

              // Calculate the planet orbital elements from the current time in days
              var N =  (planet["N1"] + planet["N2"] * currTimeD) * Math.PI / 180;
              var iPlanet = (planet["i1"] + planet["i2"] * currTimeD) * Math.PI / 180;
              var w =  (planet["w1"] + planet["w2"] * currTimeD) * Math.PI / 180;
              var a = planet["a1"] + planet["a2"] * currTimeD;
              var e = planet["e1"] + planet["e2"] * currTimeD;
              var M = (planet["M1"] + planet["M2"] * currTimeD) * Math.PI / 180;
              var E = M + e * Math.sin(M) * (1.0 + e * Math.cos(M));

              var xv = a * (Math.cos(E) - e);
              var yv = a * (Math.sqrt(1.0 - e * e) * Math.sin(E));
              var v = Math.atan2(yv, xv);

              // Calculate the distance (radius)
              var r = Math.sqrt(xv * xv + yv * yv);

              // From http://www.davidcolarusso.com/astro/
              // Modified to compensate for the right handed coordinate system of OpenGL
              var xh = r * (Math.cos(N) * Math.cos(v + w)
                            - Math.sin(N) * Math.sin(v + w) * Math.cos(iPlanet));
              var zh = -r * (Math.sin(N) * Math.cos(v + w)
                             + Math.cos(N) * Math.sin(v + w) * Math.cos(iPlanet));
              var yh = r * (Math.sin(w + v) * Math.sin(iPlanet));

              // Apply the position offset from the center of orbit to the bodies
              var centerOfOrbit = objects[planet["centerOfOrbit"]];
              object.position.set(centerOfOrbit.position.x + xh * auScale,
                                  centerOfOrbit.position.y + yh * auScale,
                                  centerOfOrbit.position.z + zh * auScale);

              // Calculate and apply the appropriate axis tilt to the bodies
              // and rotate them around the axis
              var radians = planet["tilt"] * Math.PI / 180; // tilt in radians
              object.rotation.order = 'ZXY';
              object.rotation.x = 0;
              object.rotation.y += (deltaTimeD / planet["period"]) * 2 * Math.PI;
              object.rotation.z = radians;
          }

          // rotate the Sun
          var sun = objects[SUN];
          sun.rotation.order = 'ZXY';
          sun.rotation.x = 0;
          sun.rotation.y += (deltaTimeD / planets[SUN]["period"]) * 2 * Math.PI;
          sun.rotation.z = planets[SUN]["tilt"] * Math.PI / 180; // tilt in radians

          // calculate the outer radius of the focused item
          var outerRadius = getOuterRadius(qmlView.focusedPlanet);

          // get the appropriate near plane position for the camera and animate it with QML animations
          qmlView.cameraNear = outerRadius;

          camera.near = qmlView.cameraNear;
          camera.updateProjectionMatrix();

          // Calculate and set camera position
          var cameraPosition = getNewCameraPosition(outerRadius);
          var cameraOffset = new THREE.Vector3(qmlView.xCameraOffset,
                                               qmlView.yCameraOffset,
                                               qmlView.zCameraOffset);
          cameraPosition.add(cameraOffset);
          camera.position.set(cameraPosition.x, cameraPosition.y, cameraPosition.z);

          // Calculate and set camera look-at point
          var lookAtPlanet = SUN;
          if (qmlView.focusedPlanet !== SOLAR_SYSTEM)
              lookAtPlanet = qmlView.focusedPlanet;
          var cameraLookAt = objects[lookAtPlanet].position.clone();
          var lookAtOffset = new THREE.Vector3(qmlView.xLookAtOffset,
                                               qmlView.yLookAtOffset,
                                               qmlView.zLookAtOffset);
          cameraLookAt.add(lookAtOffset);
          camera.lookAt(cameraLookAt);

          // Render the scene
          renderer.render(scene, camera);

      }

      function getOuterRadius( planet ) {

          var outerRadius = solarDistance;
          if (planet !== SOLAR_SYSTEM) {
              outerRadius = planets[planet]["radius"];
              if (planet === SATURN) {
                  outerRadius =+ saturnOuterRadius;
              } else if (planet === URANUS) {
                  outerRadius =+ uranusOuterRadius;
              } else if (planet === SUN) {
                  outerRadius = planets[planet]["radius"] / 100;
              }
          }

          return outerRadius;
      }