three.js/examples/js/misc/RollerCoaster.js

( function () {

	var RollerCoasterGeometry = function ( curve, divisions ) {

		THREE.BufferGeometry.call( this );
		var vertices = [];
		var normals = [];
		var colors = [];
		var color1 = [ 1, 1, 1 ];
		var color2 = [ 1, 1, 0 ];
		var up = new THREE.Vector3( 0, 1, 0 );
		var forward = new THREE.Vector3();
		var right = new THREE.Vector3();
		var quaternion = new THREE.Quaternion();
		var prevQuaternion = new THREE.Quaternion();
		prevQuaternion.setFromAxisAngle( up, Math.PI / 2 );
		var point = new THREE.Vector3();
		var prevPoint = new THREE.Vector3();
		prevPoint.copy( curve.getPointAt( 0 ) ); // shapes

		var step = [ new THREE.Vector3( - 0.225, 0, 0 ), new THREE.Vector3( 0, - 0.050, 0 ), new THREE.Vector3( 0, - 0.175, 0 ), new THREE.Vector3( 0, - 0.050, 0 ), new THREE.Vector3( 0.225, 0, 0 ), new THREE.Vector3( 0, - 0.175, 0 ) ];
		var PI2 = Math.PI * 2;
		var sides = 5;
		var tube1 = [];

		for ( var i = 0; i < sides; i ++ ) {

			var angle = i / sides * PI2;
			tube1.push( new THREE.Vector3( Math.sin( angle ) * 0.06, Math.cos( angle ) * 0.06, 0 ) );

		}

		var sides = 6;
		var tube2 = [];

		for ( var i = 0; i < sides; i ++ ) {

			var angle = i / sides * PI2;
			tube2.push( new THREE.Vector3( Math.sin( angle ) * 0.025, Math.cos( angle ) * 0.025, 0 ) );

		}

		var vector = new THREE.Vector3();
		var normal = new THREE.Vector3();

		function drawShape( shape, color ) {

			normal.set( 0, 0, - 1 ).applyQuaternion( quaternion );

			for ( var j = 0; j < shape.length; j ++ ) {

				vector.copy( shape[ j ] );
				vector.applyQuaternion( quaternion );
				vector.add( point );
				vertices.push( vector.x, vector.y, vector.z );
				normals.push( normal.x, normal.y, normal.z );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );

			}

			normal.set( 0, 0, 1 ).applyQuaternion( quaternion );

			for ( var j = shape.length - 1; j >= 0; j -- ) {

				vector.copy( shape[ j ] );
				vector.applyQuaternion( quaternion );
				vector.add( point );
				vertices.push( vector.x, vector.y, vector.z );
				normals.push( normal.x, normal.y, normal.z );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );

			}

		}

		var vector1 = new THREE.Vector3();
		var vector2 = new THREE.Vector3();
		var vector3 = new THREE.Vector3();
		var vector4 = new THREE.Vector3();
		var normal1 = new THREE.Vector3();
		var normal2 = new THREE.Vector3();
		var normal3 = new THREE.Vector3();
		var normal4 = new THREE.Vector3();

		function extrudeShape( shape, offset, color ) {

			for ( var j = 0, jl = shape.length; j < jl; j ++ ) {

				var point1 = shape[ j ];
				var point2 = shape[ ( j + 1 ) % jl ];
				vector1.copy( point1 ).add( offset );
				vector1.applyQuaternion( quaternion );
				vector1.add( point );
				vector2.copy( point2 ).add( offset );
				vector2.applyQuaternion( quaternion );
				vector2.add( point );
				vector3.copy( point2 ).add( offset );
				vector3.applyQuaternion( prevQuaternion );
				vector3.add( prevPoint );
				vector4.copy( point1 ).add( offset );
				vector4.applyQuaternion( prevQuaternion );
				vector4.add( prevPoint );
				vertices.push( vector1.x, vector1.y, vector1.z );
				vertices.push( vector2.x, vector2.y, vector2.z );
				vertices.push( vector4.x, vector4.y, vector4.z );
				vertices.push( vector2.x, vector2.y, vector2.z );
				vertices.push( vector3.x, vector3.y, vector3.z );
				vertices.push( vector4.x, vector4.y, vector4.z ); //

				normal1.copy( point1 );
				normal1.applyQuaternion( quaternion );
				normal1.normalize();
				normal2.copy( point2 );
				normal2.applyQuaternion( quaternion );
				normal2.normalize();
				normal3.copy( point2 );
				normal3.applyQuaternion( prevQuaternion );
				normal3.normalize();
				normal4.copy( point1 );
				normal4.applyQuaternion( prevQuaternion );
				normal4.normalize();
				normals.push( normal1.x, normal1.y, normal1.z );
				normals.push( normal2.x, normal2.y, normal2.z );
				normals.push( normal4.x, normal4.y, normal4.z );
				normals.push( normal2.x, normal2.y, normal2.z );
				normals.push( normal3.x, normal3.y, normal3.z );
				normals.push( normal4.x, normal4.y, normal4.z );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );
				colors.push( color[ 0 ], color[ 1 ], color[ 2 ] );

			}

		}

		var offset = new THREE.Vector3();

		for ( var i = 1; i <= divisions; i ++ ) {

			point.copy( curve.getPointAt( i / divisions ) );
			up.set( 0, 1, 0 );
			forward.subVectors( point, prevPoint ).normalize();
			right.crossVectors( up, forward ).normalize();
			up.crossVectors( forward, right );
			var angle = Math.atan2( forward.x, forward.z );
			quaternion.setFromAxisAngle( up, angle );

			if ( i % 2 === 0 ) {

				drawShape( step, color2 );

			}

			extrudeShape( tube1, offset.set( 0, - 0.125, 0 ), color2 );
			extrudeShape( tube2, offset.set( 0.2, 0, 0 ), color1 );
			extrudeShape( tube2, offset.set( - 0.2, 0, 0 ), color1 );
			prevPoint.copy( point );
			prevQuaternion.copy( quaternion );

		} // console.log( vertices.length );


		this.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );
		this.setAttribute( 'normal', new THREE.BufferAttribute( new Float32Array( normals ), 3 ) );
		this.setAttribute( 'color', new THREE.BufferAttribute( new Float32Array( colors ), 3 ) );

	};

	RollerCoasterGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );

	var RollerCoasterLiftersGeometry = function ( curve, divisions ) {

		THREE.BufferGeometry.call( this );
		var vertices = [];
		var normals = [];
		var quaternion = new THREE.Quaternion();
		var up = new THREE.Vector3( 0, 1, 0 );
		var point = new THREE.Vector3();
		var tangent = new THREE.Vector3(); // shapes

		var tube1 = [ new THREE.Vector3( 0, 0.05, - 0.05 ), new THREE.Vector3( 0, 0.05, 0.05 ), new THREE.Vector3( 0, - 0.05, 0 ) ];
		var tube2 = [ new THREE.Vector3( - 0.05, 0, 0.05 ), new THREE.Vector3( - 0.05, 0, - 0.05 ), new THREE.Vector3( 0.05, 0, 0 ) ];
		var tube3 = [ new THREE.Vector3( 0.05, 0, - 0.05 ), new THREE.Vector3( 0.05, 0, 0.05 ), new THREE.Vector3( - 0.05, 0, 0 ) ];
		var vector1 = new THREE.Vector3();
		var vector2 = new THREE.Vector3();
		var vector3 = new THREE.Vector3();
		var vector4 = new THREE.Vector3();
		var normal1 = new THREE.Vector3();
		var normal2 = new THREE.Vector3();
		var normal3 = new THREE.Vector3();
		var normal4 = new THREE.Vector3();

		function extrudeShape( shape, fromPoint, toPoint ) {

			for ( var j = 0, jl = shape.length; j < jl; j ++ ) {

				var point1 = shape[ j ];
				var point2 = shape[ ( j + 1 ) % jl ];
				vector1.copy( point1 );
				vector1.applyQuaternion( quaternion );
				vector1.add( fromPoint );
				vector2.copy( point2 );
				vector2.applyQuaternion( quaternion );
				vector2.add( fromPoint );
				vector3.copy( point2 );
				vector3.applyQuaternion( quaternion );
				vector3.add( toPoint );
				vector4.copy( point1 );
				vector4.applyQuaternion( quaternion );
				vector4.add( toPoint );
				vertices.push( vector1.x, vector1.y, vector1.z );
				vertices.push( vector2.x, vector2.y, vector2.z );
				vertices.push( vector4.x, vector4.y, vector4.z );
				vertices.push( vector2.x, vector2.y, vector2.z );
				vertices.push( vector3.x, vector3.y, vector3.z );
				vertices.push( vector4.x, vector4.y, vector4.z ); //

				normal1.copy( point1 );
				normal1.applyQuaternion( quaternion );
				normal1.normalize();
				normal2.copy( point2 );
				normal2.applyQuaternion( quaternion );
				normal2.normalize();
				normal3.copy( point2 );
				normal3.applyQuaternion( quaternion );
				normal3.normalize();
				normal4.copy( point1 );
				normal4.applyQuaternion( quaternion );
				normal4.normalize();
				normals.push( normal1.x, normal1.y, normal1.z );
				normals.push( normal2.x, normal2.y, normal2.z );
				normals.push( normal4.x, normal4.y, normal4.z );
				normals.push( normal2.x, normal2.y, normal2.z );
				normals.push( normal3.x, normal3.y, normal3.z );
				normals.push( normal4.x, normal4.y, normal4.z );

			}

		}

		var fromPoint = new THREE.Vector3();
		var toPoint = new THREE.Vector3();

		for ( var i = 1; i <= divisions; i ++ ) {

			point.copy( curve.getPointAt( i / divisions ) );
			tangent.copy( curve.getTangentAt( i / divisions ) );
			var angle = Math.atan2( tangent.x, tangent.z );
			quaternion.setFromAxisAngle( up, angle ); //

			if ( point.y > 10 ) {

				fromPoint.set( - 0.75, - 0.35, 0 );
				fromPoint.applyQuaternion( quaternion );
				fromPoint.add( point );
				toPoint.set( 0.75, - 0.35, 0 );
				toPoint.applyQuaternion( quaternion );
				toPoint.add( point );
				extrudeShape( tube1, fromPoint, toPoint );
				fromPoint.set( - 0.7, - 0.3, 0 );
				fromPoint.applyQuaternion( quaternion );
				fromPoint.add( point );
				toPoint.set( - 0.7, - point.y, 0 );
				toPoint.applyQuaternion( quaternion );
				toPoint.add( point );
				extrudeShape( tube2, fromPoint, toPoint );
				fromPoint.set( 0.7, - 0.3, 0 );
				fromPoint.applyQuaternion( quaternion );
				fromPoint.add( point );
				toPoint.set( 0.7, - point.y, 0 );
				toPoint.applyQuaternion( quaternion );
				toPoint.add( point );
				extrudeShape( tube3, fromPoint, toPoint );

			} else {

				fromPoint.set( 0, - 0.2, 0 );
				fromPoint.applyQuaternion( quaternion );
				fromPoint.add( point );
				toPoint.set( 0, - point.y, 0 );
				toPoint.applyQuaternion( quaternion );
				toPoint.add( point );
				extrudeShape( tube3, fromPoint, toPoint );

			}

		}

		this.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );
		this.setAttribute( 'normal', new THREE.BufferAttribute( new Float32Array( normals ), 3 ) );

	};

	RollerCoasterLiftersGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );

	var RollerCoasterShadowGeometry = function ( curve, divisions ) {

		THREE.BufferGeometry.call( this );
		var vertices = [];
		var up = new THREE.Vector3( 0, 1, 0 );
		var forward = new THREE.Vector3();
		var quaternion = new THREE.Quaternion();
		var prevQuaternion = new THREE.Quaternion();
		prevQuaternion.setFromAxisAngle( up, Math.PI / 2 );
		var point = new THREE.Vector3();
		var prevPoint = new THREE.Vector3();
		prevPoint.copy( curve.getPointAt( 0 ) );
		prevPoint.y = 0;
		var vector1 = new THREE.Vector3();
		var vector2 = new THREE.Vector3();
		var vector3 = new THREE.Vector3();
		var vector4 = new THREE.Vector3();

		for ( var i = 1; i <= divisions; i ++ ) {

			point.copy( curve.getPointAt( i / divisions ) );
			point.y = 0;
			forward.subVectors( point, prevPoint );
			var angle = Math.atan2( forward.x, forward.z );
			quaternion.setFromAxisAngle( up, angle );
			vector1.set( - 0.3, 0, 0 );
			vector1.applyQuaternion( quaternion );
			vector1.add( point );
			vector2.set( 0.3, 0, 0 );
			vector2.applyQuaternion( quaternion );
			vector2.add( point );
			vector3.set( 0.3, 0, 0 );
			vector3.applyQuaternion( prevQuaternion );
			vector3.add( prevPoint );
			vector4.set( - 0.3, 0, 0 );
			vector4.applyQuaternion( prevQuaternion );
			vector4.add( prevPoint );
			vertices.push( vector1.x, vector1.y, vector1.z );
			vertices.push( vector2.x, vector2.y, vector2.z );
			vertices.push( vector4.x, vector4.y, vector4.z );
			vertices.push( vector2.x, vector2.y, vector2.z );
			vertices.push( vector3.x, vector3.y, vector3.z );
			vertices.push( vector4.x, vector4.y, vector4.z );
			prevPoint.copy( point );
			prevQuaternion.copy( quaternion );

		}

		this.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );

	};

	RollerCoasterShadowGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );

	var SkyGeometry = function () {

		THREE.BufferGeometry.call( this );
		var vertices = [];

		for ( var i = 0; i < 100; i ++ ) {

			var x = Math.random() * 800 - 400;
			var y = Math.random() * 50 + 50;
			var z = Math.random() * 800 - 400;
			var size = Math.random() * 40 + 20;
			vertices.push( x - size, y, z - size );
			vertices.push( x + size, y, z - size );
			vertices.push( x - size, y, z + size );
			vertices.push( x + size, y, z - size );
			vertices.push( x + size, y, z + size );
			vertices.push( x - size, y, z + size );

		}

		this.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );

	};

	SkyGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );

	var TreesGeometry = function ( landscape ) {

		THREE.BufferGeometry.call( this );
		var vertices = [];
		var colors = [];
		var raycaster = new THREE.Raycaster();
		raycaster.ray.direction.set( 0, - 1, 0 );

		for ( var i = 0; i < 2000; i ++ ) {

			var x = Math.random() * 500 - 250;
			var z = Math.random() * 500 - 250;
			raycaster.ray.origin.set( x, 50, z );
			var intersections = raycaster.intersectObject( landscape );
			if ( intersections.length === 0 ) continue;
			var y = intersections[ 0 ].point.y;
			var height = Math.random() * 5 + 0.5;
			var angle = Math.random() * Math.PI * 2;
			vertices.push( x + Math.sin( angle ), y, z + Math.cos( angle ) );
			vertices.push( x, y + height, z );
			vertices.push( x + Math.sin( angle + Math.PI ), y, z + Math.cos( angle + Math.PI ) );
			angle += Math.PI / 2;
			vertices.push( x + Math.sin( angle ), y, z + Math.cos( angle ) );
			vertices.push( x, y + height, z );
			vertices.push( x + Math.sin( angle + Math.PI ), y, z + Math.cos( angle + Math.PI ) );
			var random = Math.random() * 0.1;

			for ( var j = 0; j < 6; j ++ ) {

				colors.push( 0.2 + random, 0.4 + random, 0 );

			}

		}

		this.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array( vertices ), 3 ) );
		this.setAttribute( 'color', new THREE.BufferAttribute( new Float32Array( colors ), 3 ) );

	};

	TreesGeometry.prototype = Object.create( THREE.BufferGeometry.prototype );

	THREE.RollerCoasterGeometry = RollerCoasterGeometry;
	THREE.RollerCoasterLiftersGeometry = RollerCoasterLiftersGeometry;
	THREE.RollerCoasterShadowGeometry = RollerCoasterShadowGeometry;
	THREE.SkyGeometry = SkyGeometry;
	THREE.TreesGeometry = TreesGeometry;

} )();