cione-comp-lib
Version:
`$ yarn add cione-comp-lib` 或者 `$ npm i cione-comp-lib -S`
87 lines (86 loc) • 2.81 kB
JavaScript
import Geometry from "../Geometry.mjs";
import BoundingBox from "../math/BoundingBox.mjs";
var Sphere = Geometry.extend(
{
dynamic: false,
widthSegments: 40,
heightSegments: 20,
phiStart: 0,
phiLength: Math.PI * 2,
thetaStart: 0,
thetaLength: Math.PI,
radius: 1
},
function() {
this.build();
},
{
build: function() {
var heightSegments = this.heightSegments;
var widthSegments = this.widthSegments;
var positionAttr = this.attributes.position;
var texcoordAttr = this.attributes.texcoord0;
var normalAttr = this.attributes.normal;
var vertexCount = (widthSegments + 1) * (heightSegments + 1);
positionAttr.init(vertexCount);
texcoordAttr.init(vertexCount);
normalAttr.init(vertexCount);
var IndicesCtor = vertexCount > 65535 ? Uint32Array : Uint16Array;
var indices = this.indices = new IndicesCtor(widthSegments * heightSegments * 6);
var x, y, z, u, v, i, j;
var radius = this.radius;
var phiStart = this.phiStart;
var phiLength = this.phiLength;
var thetaStart = this.thetaStart;
var thetaLength = this.thetaLength;
var radius = this.radius;
var pos = [];
var uv = [];
var offset = 0;
var divider = 1 / radius;
for (j = 0; j <= heightSegments; j++) {
for (i = 0; i <= widthSegments; i++) {
u = i / widthSegments;
v = j / heightSegments;
x = -radius * Math.cos(phiStart + u * phiLength) * Math.sin(thetaStart + v * thetaLength);
y = radius * Math.cos(thetaStart + v * thetaLength);
z = radius * Math.sin(phiStart + u * phiLength) * Math.sin(thetaStart + v * thetaLength);
pos[0] = x;
pos[1] = y;
pos[2] = z;
uv[0] = u;
uv[1] = v;
positionAttr.set(offset, pos);
texcoordAttr.set(offset, uv);
pos[0] *= divider;
pos[1] *= divider;
pos[2] *= divider;
normalAttr.set(offset, pos);
offset++;
}
}
var i1, i2, i3, i4;
var len = widthSegments + 1;
var n = 0;
for (j = 0; j < heightSegments; j++) {
for (i = 0; i < widthSegments; i++) {
i2 = j * len + i;
i1 = j * len + i + 1;
i4 = (j + 1) * len + i + 1;
i3 = (j + 1) * len + i;
indices[n++] = i1;
indices[n++] = i2;
indices[n++] = i4;
indices[n++] = i2;
indices[n++] = i3;
indices[n++] = i4;
}
}
this.boundingBox = new BoundingBox();
this.boundingBox.max.set(radius, radius, radius);
this.boundingBox.min.set(-radius, -radius, -radius);
}
}
);
var SphereGeometry = Sphere;
export { SphereGeometry as default };