three
Version:
JavaScript 3D library
261 lines (167 loc) • 6.15 kB
JavaScript
import {
Curve,
Geometry,
ParametricGeometry,
Vector3
} from "../../../build/three.module.js";
/**
* Experimenting of primitive geometry creation using Surface Parametric equations
*/
var ParametricGeometries = {
klein: function ( v, u, target ) {
u *= Math.PI;
v *= 2 * Math.PI;
u = u * 2;
var x, y, z;
if ( u < Math.PI ) {
x = 3 * Math.cos( u ) * ( 1 + Math.sin( u ) ) + ( 2 * ( 1 - Math.cos( u ) / 2 ) ) * Math.cos( u ) * Math.cos( v );
z = - 8 * Math.sin( u ) - 2 * ( 1 - Math.cos( u ) / 2 ) * Math.sin( u ) * Math.cos( v );
} else {
x = 3 * Math.cos( u ) * ( 1 + Math.sin( u ) ) + ( 2 * ( 1 - Math.cos( u ) / 2 ) ) * Math.cos( v + Math.PI );
z = - 8 * Math.sin( u );
}
y = - 2 * ( 1 - Math.cos( u ) / 2 ) * Math.sin( v );
target.set( x, y, z );
},
plane: function ( width, height ) {
return function ( u, v, target ) {
var x = u * width;
var y = 0;
var z = v * height;
target.set( x, y, z );
};
},
mobius: function ( u, t, target ) {
// flat mobius strip
// http://www.wolframalpha.com/input/?i=M%C3%B6bius+strip+parametric+equations&lk=1&a=ClashPrefs_*Surface.MoebiusStrip.SurfaceProperty.ParametricEquations-
u = u - 0.5;
var v = 2 * Math.PI * t;
var x, y, z;
var a = 2;
x = Math.cos( v ) * ( a + u * Math.cos( v / 2 ) );
y = Math.sin( v ) * ( a + u * Math.cos( v / 2 ) );
z = u * Math.sin( v / 2 );
target.set( x, y, z );
},
mobius3d: function ( u, t, target ) {
// volumetric mobius strip
u *= Math.PI;
t *= 2 * Math.PI;
u = u * 2;
var phi = u / 2;
var major = 2.25, a = 0.125, b = 0.65;
var x, y, z;
x = a * Math.cos( t ) * Math.cos( phi ) - b * Math.sin( t ) * Math.sin( phi );
z = a * Math.cos( t ) * Math.sin( phi ) + b * Math.sin( t ) * Math.cos( phi );
y = ( major + x ) * Math.sin( u );
x = ( major + x ) * Math.cos( u );
target.set( x, y, z );
}
};
/*********************************************
*
* Parametric Replacement for TubeGeometry
*
*********************************************/
ParametricGeometries.TubeGeometry = function ( path, segments, radius, segmentsRadius, closed ) {
this.path = path;
this.segments = segments || 64;
this.radius = radius || 1;
this.segmentsRadius = segmentsRadius || 8;
this.closed = closed || false;
var scope = this, numpoints = this.segments + 1;
var frames = path.computeFrenetFrames( segments, closed ),
tangents = frames.tangents,
normals = frames.normals,
binormals = frames.binormals;
// proxy internals
this.tangents = tangents;
this.normals = normals;
this.binormals = binormals;
var position = new Vector3();
var ParametricTube = function ( u, v, target ) {
v *= 2 * Math.PI;
var i = u * ( numpoints - 1 );
i = Math.floor( i );
path.getPointAt( u, position );
var normal = normals[ i ];
var binormal = binormals[ i ];
var cx = - scope.radius * Math.cos( v ); // TODO: Hack: Negating it so it faces outside.
var cy = scope.radius * Math.sin( v );
position.x += cx * normal.x + cy * binormal.x;
position.y += cx * normal.y + cy * binormal.y;
position.z += cx * normal.z + cy * binormal.z;
target.copy( position );
};
ParametricGeometry.call( this, ParametricTube, segments, segmentsRadius );
};
ParametricGeometries.TubeGeometry.prototype = Object.create( Geometry.prototype );
ParametricGeometries.TubeGeometry.prototype.constructor = ParametricGeometries.TubeGeometry;
/*********************************************
*
* Parametric Replacement for TorusKnotGeometry
*
*********************************************/
ParametricGeometries.TorusKnotGeometry = function ( radius, tube, segmentsT, segmentsR, p, q ) {
this.radius = radius || 200;
this.tube = tube || 40;
this.segmentsT = segmentsT || 64;
this.segmentsR = segmentsR || 8;
this.p = p || 2;
this.q = q || 3;
function TorusKnotCurve() {
Curve.call( this );
}
TorusKnotCurve.prototype = Object.create( Curve.prototype );
TorusKnotCurve.prototype.constructor = TorusKnotCurve;
TorusKnotCurve.prototype.getPoint = function ( t, optionalTarget ) {
var point = optionalTarget || new Vector3();
t *= Math.PI * 2;
var r = 0.5;
var x = ( 1 + r * Math.cos( q * t ) ) * Math.cos( p * t );
var y = ( 1 + r * Math.cos( q * t ) ) * Math.sin( p * t );
var z = r * Math.sin( q * t );
return point.set( x, y, z ).multiplyScalar( radius );
};
var segments = segmentsT;
var radiusSegments = segmentsR;
var extrudePath = new TorusKnotCurve();
ParametricGeometries.TubeGeometry.call( this, extrudePath, segments, tube, radiusSegments, true, false );
};
ParametricGeometries.TorusKnotGeometry.prototype = Object.create( Geometry.prototype );
ParametricGeometries.TorusKnotGeometry.prototype.constructor = ParametricGeometries.TorusKnotGeometry;
/*********************************************
*
* Parametric Replacement for SphereGeometry
*
*********************************************/
ParametricGeometries.SphereGeometry = function ( size, u, v ) {
function sphere( u, v, target ) {
u *= Math.PI;
v *= 2 * Math.PI;
var x = size * Math.sin( u ) * Math.cos( v );
var y = size * Math.sin( u ) * Math.sin( v );
var z = size * Math.cos( u );
target.set( x, y, z );
}
ParametricGeometry.call( this, sphere, u, v );
};
ParametricGeometries.SphereGeometry.prototype = Object.create( Geometry.prototype );
ParametricGeometries.SphereGeometry.prototype.constructor = ParametricGeometries.SphereGeometry;
/*********************************************
*
* Parametric Replacement for PlaneGeometry
*
*********************************************/
ParametricGeometries.PlaneGeometry = function ( width, depth, segmentsWidth, segmentsDepth ) {
function plane( u, v, target ) {
var x = u * width;
var y = 0;
var z = v * depth;
target.set( x, y, z );
}
ParametricGeometry.call( this, plane, segmentsWidth, segmentsDepth );
};
ParametricGeometries.PlaneGeometry.prototype = Object.create( Geometry.prototype );
ParametricGeometries.PlaneGeometry.prototype.constructor = ParametricGeometries.PlaneGeometry;
export { ParametricGeometries };