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724 | /**
* GitHub Repo : https://github.com/Sean-Bradley/THREE-CSGMesh
* License : MIT
*
* Original work copyright (c) 2011 Evan Wallace (http://madebyevan.com/), under the MIT license.
* THREE.js rework by thrax
*
* # class CSG
* Holds a binary space partition tree representing a 3D solid. Two solids can
* be combined using the `union()`, `subtract()`, and `intersect()` methods.
*
* Differences Copyright 2020-2022 Sean Bradley : https://sbcode.net/threejs/
* - Started with CSGMesh.js and csg-lib.js from https://github.com/manthrax/THREE-CSGMesh
* - Converted to TypeScript by adding type annotations to all variables
* - Converted var to const and let
* - Some Refactoring
* - support for three r141
*/
import * as THREE from 'three'
class CSG {
polygons: Polygon[]
constructor() {
this.polygons = []
}
clone() {
const csg = new CSG()
csg.polygons = this.polygons.map(function (p) {
return p.clone()
})
return csg
}
toPolygons() {
return this.polygons
}
union(csg: CSG) {
let a = new Node(this.clone().polygons)
let b = new Node(csg.clone().polygons)
a.clipTo(b)
b.clipTo(a)
b.invert()
b.clipTo(a)
b.invert()
a.build(b.allPolygons())
return CSG.fromPolygons(a.allPolygons())
}
subtract(csg: CSG) {
let a = new Node(this.clone().polygons)
let b = new Node(csg.clone().polygons)
a.invert()
a.clipTo(b)
b.clipTo(a)
b.invert()
b.clipTo(a)
b.invert()
a.build(b.allPolygons())
a.invert()
return CSG.fromPolygons(a.allPolygons())
}
intersect(csg: CSG) {
let a = new Node(this.clone().polygons)
let b = new Node(csg.clone().polygons)
a.invert()
b.clipTo(a)
b.invert()
a.clipTo(b)
b.clipTo(a)
a.build(b.allPolygons())
a.invert()
return CSG.fromPolygons(a.allPolygons())
}
// Return a new CSG solid with solid and empty space switched. This solid is
// not modified.
inverse() {
const csg = this.clone()
csg.polygons.map(function (p) {
p.flip()
})
return csg
}
// Construct a CSG solid from a list of `Polygon` instances.
static fromPolygons = function (polygons: Polygon[]) {
const csg = new CSG()
csg.polygons = polygons
return csg
}
static fromGeometry = function (
geom: THREE.BufferGeometry,
objectIndex?: object
) {
let polys = []
let posattr = geom.attributes.position
let normalattr = geom.attributes.normal
let uvattr = geom.attributes.uv
let colorattr = geom.attributes.color
let index: number[]
if (geom.index) {
index = geom.index.array as number[]
} else {
index = new Array((posattr.array.length / posattr.itemSize) | 0)
for (let i = 0; i < index.length; i++) index[i] = i
}
let triCount = (index.length / 3) | 0
polys = new Array(triCount)
for (let i = 0, pli = 0, l = index.length; i < l; i += 3, pli++) {
let vertices = new Array(3)
for (let j = 0; j < 3; j++) {
let vi = index[i + j]
let vp = vi * 3
let vt = vi * 2
let x = posattr.array[vp]
let y = posattr.array[vp + 1]
let z = posattr.array[vp + 2]
let nx = normalattr.array[vp]
let ny = normalattr.array[vp + 1]
let nz = normalattr.array[vp + 2]
let u = uvattr.array[vt]
let v = uvattr.array[vt + 1]
vertices[j] = new Vertex(
{
x: x,
y: y,
z: z,
} as Vector,
{
x: nx,
y: ny,
z: nz,
} as Vector,
{
x: u,
y: v,
z: 0,
} as Vector,
colorattr &&
({
x: colorattr.array[vt],
y: colorattr.array[vt + 1],
z: colorattr.array[vt + 2],
} as Vector)
)
}
polys[pli] = new Polygon(vertices, objectIndex)
}
return CSG.fromPolygons(polys)
}
private static ttvv0 = new THREE.Vector3()
private static tmpm3 = new THREE.Matrix3()
static fromMesh = function (mesh: THREE.Mesh, objectIndex?: object) {
const csg = CSG.fromGeometry(mesh.geometry, objectIndex)
CSG.tmpm3.getNormalMatrix(mesh.matrix)
for (let i = 0; i < csg.polygons.length; i++) {
let p = csg.polygons[i]
for (let j = 0; j < p.vertices.length; j++) {
let v = p.vertices[j]
v.pos.copy(
CSG.ttvv0
.copy(new THREE.Vector3(v.pos.x, v.pos.y, v.pos.z))
.applyMatrix4(mesh.matrix)
)
v.normal.copy(
CSG.ttvv0
.copy(
new THREE.Vector3(
v.normal.x,
v.normal.y,
v.normal.z
)
)
.applyMatrix3(CSG.tmpm3)
)
}
}
return csg
}
static nbuf3 = (ct: number) => {
return {
top: 0,
array: new Float32Array(ct),
write: function (v: Vector) {
this.array[this.top++] = v.x
this.array[this.top++] = v.y
this.array[this.top++] = v.z
},
}
}
static nbuf2 = (ct: number) => {
return {
top: 0,
array: new Float32Array(ct),
write: function (v: Vector) {
this.array[this.top++] = v.x
this.array[this.top++] = v.y
},
}
}
static toMesh = function (
csg: CSG,
toMatrix: THREE.Matrix4,
toMaterial?: THREE.Material
) {
let ps = csg.polygons
let geom: THREE.BufferGeometry
let triCount = 0
ps.forEach((p) => (triCount += p.vertices.length - 2))
geom = new THREE.BufferGeometry()
let vertices = CSG.nbuf3(triCount * 3 * 3)
let normals = CSG.nbuf3(triCount * 3 * 3)
let uvs = CSG.nbuf2(triCount * 2 * 3)
let colors: any
let grps: any[] = []
ps.forEach((p) => {
let pvs = p.vertices
let pvlen = pvs.length
if (p.shared !== undefined) {
if (!grps[p.shared]) grps[p.shared] = []
}
if (pvlen && pvs[0].color !== undefined) {
if (!colors) colors = CSG.nbuf3(triCount * 3 * 3)
}
for (let j = 3; j <= pvlen; j++) {
p.shared !== undefined &&
grps[p.shared].push(
vertices.top / 3,
vertices.top / 3 + 1,
vertices.top / 3 + 2
)
vertices.write(pvs[0].pos)
vertices.write(pvs[j - 2].pos)
vertices.write(pvs[j - 1].pos)
normals.write(pvs[0].normal)
normals.write(pvs[j - 2].normal)
normals.write(pvs[j - 1].normal)
uvs.write(pvs[0].uv)
uvs.write(pvs[j - 2].uv)
uvs.write(pvs[j - 1].uv)
colors &&
(colors.write(pvs[0].color) ||
colors.write(pvs[j - 2].color) ||
colors.write(pvs[j - 1].color))
}
})
geom.setAttribute(
'position',
new THREE.BufferAttribute(vertices.array, 3)
)
geom.setAttribute('normal', new THREE.BufferAttribute(normals.array, 3))
geom.setAttribute('uv', new THREE.BufferAttribute(uvs.array, 2))
colors &&
geom.setAttribute(
'color',
new THREE.BufferAttribute(colors.array, 3)
)
if (grps.length) {
let index: any[] = []
let gbase = 0
for (let gi = 0; gi < grps.length; gi++) {
geom.addGroup(gbase, grps[gi].length, gi)
gbase += grps[gi].length
index = index.concat(grps[gi])
}
geom.setIndex(index)
}
let inv = new THREE.Matrix4().copy(toMatrix).invert()
geom.applyMatrix4(inv)
geom.computeBoundingSphere()
geom.computeBoundingBox()
let m = new THREE.Mesh(geom, toMaterial)
m.matrix.copy(toMatrix)
m.matrix.decompose(m.position, m.quaternion, m.scale)
m.rotation.setFromQuaternion(m.quaternion)
m.updateMatrixWorld()
m.castShadow = m.receiveShadow = true
return m
}
}
// # class Vector
// Represents a 3D vector.
//
// Example usage:
//
// new CSG.Vector(1, 2, 3);
class Vector {
x: number
y: number
z: number
constructor(x = 0, y = 0, z = 0) {
this.x = x
this.y = y
this.z = z
}
copy(v: any) {
this.x = v.x
this.y = v.y
this.z = v.z
return this
}
clone() {
return new Vector(this.x, this.y, this.z)
}
negate() {
this.x *= -1
this.y *= -1
this.z *= -1
return this
}
add(a: Vector) {
this.x += a.x
this.y += a.y
this.z += a.z
return this
}
sub(a: Vector) {
this.x -= a.x
this.y -= a.y
this.z -= a.z
return this
}
times(a: number) {
this.x *= a
this.y *= a
this.z *= a
return this
}
dividedBy(a: number) {
this.x /= a
this.y /= a
this.z /= a
return this
}
lerp(a: Vector, t: number) {
return this.add(tv0.copy(a).sub(this).times(t))
}
unit() {
return this.dividedBy(this.length())
}
length() {
return Math.sqrt(this.x ** 2 + this.y ** 2 + this.z ** 2)
}
normalize() {
return this.unit()
}
cross(b: Vector) {
let a = this
const ax = a.x,
ay = a.y,
az = a.z
const bx = b.x,
by = b.y,
bz = b.z
this.x = ay * bz - az * by
this.y = az * bx - ax * bz
this.z = ax * by - ay * bx
return this
}
dot(b: Vector) {
return this.x * b.x + this.y * b.y + this.z * b.z
}
}
//Temporaries used to avoid internal allocation..
let tv0 = new Vector(0, 0, 0)
let tv1 = new Vector(0, 0, 0)
// # class Vertex
// Represents a vertex of a polygon. Use your own vertex class instead of this
// one to provide additional features like texture coordinates and vertex
// colors. Custom vertex classes need to provide a `pos` property and `clone()`,
// `flip()`, and `interpolate()` methods that behave analogous to the ones
// defined by `CSG.Vertex`. This class provides `normal` so convenience
// functions like `CSG.sphere()` can return a smooth vertex normal, but `normal`
// is not used anywhere else.
class Vertex {
pos: Vector
normal: Vector
uv: Vector
color: any
constructor(pos: Vector, normal: Vector, uv?: Vector, color?: Vector) {
this.pos = new Vector().copy(pos)
this.normal = new Vector().copy(normal)
this.uv = new Vector().copy(uv)
this.uv.z = 0
color && (this.color = new Vector().copy(color))
}
clone() {
return new Vertex(this.pos, this.normal, this.uv, this.color)
}
// Invert all orientation-specific data (e.g. vertex normal). Called when the
// orientation of a polygon is flipped.
flip() {
this.normal.negate()
}
// Create a new vertex between this vertex and `other` by linearly
// interpolating all properties using a parameter of `t`. Subclasses should
// override this to interpolate additional properties.
interpolate(other: Vertex, t: number) {
return new Vertex(
this.pos.clone().lerp(other.pos, t),
this.normal.clone().lerp(other.normal, t),
this.uv.clone().lerp(other.uv, t),
this.color && other.color && this.color.clone().lerp(other.color, t)
)
}
}
// # class Plane
// Represents a plane in 3D space.
class Plane {
normal: Vector
w: number
constructor(normal: Vector, w: number) {
this.normal = normal
this.w = w
}
clone() {
return new Plane(this.normal.clone(), this.w)
}
flip() {
this.normal.negate()
this.w = -this.w
}
// Split `polygon` by this plane if needed, then put the polygon or polygon
// fragments in the appropriate lists. Coplanar polygons go into either
// `coplanarFront` or `coplanarBack` depending on their orientation with
// respect to this plane. Polygons in front or in back of this plane go into
// either `front` or `back`.
splitPolygon(
polygon: Polygon,
coplanarFront: Polygon[],
coplanarBack: Polygon[],
front: Polygon[],
back: Polygon[]
) {
const COPLANAR = 0
const FRONT = 1
const BACK = 2
const SPANNING = 3
// Classify each point as well as the entire polygon into one of the above
// four classes.
let polygonType = 0
let types = []
for (let i = 0; i < polygon.vertices.length; i++) {
let t = this.normal.dot(polygon.vertices[i].pos) - this.w
let type =
t < -Plane.EPSILON ? BACK : t > Plane.EPSILON ? FRONT : COPLANAR
polygonType |= type
types.push(type)
}
// Put the polygon in the correct list, splitting it when necessary.
switch (polygonType) {
case COPLANAR:
;(this.normal.dot(polygon.plane.normal) > 0
? coplanarFront
: coplanarBack
).push(polygon)
break
case FRONT:
front.push(polygon)
break
case BACK:
back.push(polygon)
break
case SPANNING:
let f = [],
b = []
for (let i = 0; i < polygon.vertices.length; i++) {
let j = (i + 1) % polygon.vertices.length
let ti = types[i],
tj = types[j]
let vi = polygon.vertices[i],
vj = polygon.vertices[j]
if (ti != BACK) f.push(vi)
if (ti != FRONT) b.push(ti != BACK ? vi.clone() : vi)
if ((ti | tj) == SPANNING) {
let t =
(this.w - this.normal.dot(vi.pos)) /
this.normal.dot(tv0.copy(vj.pos).sub(vi.pos))
let v = vi.interpolate(vj, t)
f.push(v)
b.push(v.clone())
}
}
if (f.length >= 3) front.push(new Polygon(f, polygon.shared))
if (b.length >= 3) back.push(new Polygon(b, polygon.shared))
break
}
}
// `Plane.EPSILON` is the tolerance used by `splitPolygon()` to decide if a
// point is on the plane.
static EPSILON = 1e-5
static fromPoints = function (a: Vector, b: Vector, c: Vector) {
let n = tv0.copy(b).sub(a).cross(tv1.copy(c).sub(a)).normalize()
return new Plane(n.clone(), n.dot(a))
}
}
// # class Polygon
// Represents a convex polygon. The vertices used to initialize a polygon must
// be coplanar and form a convex loop. They do not have to be `Vertex`
// instances but they must behave similarly (duck typing can be used for
// customization).
//
// Each convex polygon has a `shared` property, which is shared between all
// polygons that are clones of each other or were split from the same polygon.
// This can be used to define per-polygon properties (such as surface color).
class Polygon {
vertices: Vertex[]
shared: any
plane: Plane
constructor(vertices: Vertex[], shared?: any) {
this.vertices = vertices
this.shared = shared
this.plane = Plane.fromPoints(
vertices[0].pos as Vector,
vertices[1].pos as Vector,
vertices[2].pos as Vector
)
}
clone() {
return new Polygon(
this.vertices.map((v) => v.clone()),
this.shared
)
}
flip() {
this.vertices.reverse().map((v) => v.flip())
this.plane.flip()
}
}
// # class Node
// Holds a node in a BSP tree. A BSP tree is built from a collection of polygons
// by picking a polygon to split along. That polygon (and all other coplanar
// polygons) are added directly to that node and the other polygons are added to
// the front and/or back subtrees. This is not a leafy BSP tree since there is
// no distinction between internal and leaf nodes.
class Node {
plane?: Plane
front?: Node
back?: Node
polygons: Polygon[]
constructor(polygons?: Polygon[]) {
this.polygons = []
if (polygons) this.build(polygons)
}
clone() {
let node = new Node()
node.plane = this.plane && this.plane.clone()
node.front = this.front && this.front.clone()
node.back = this.back && this.back.clone()
node.polygons = this.polygons.map((p) => p.clone())
return node
}
// Convert solid space to empty space and empty space to solid space.
invert() {
for (let i = 0; i < this.polygons.length; i++) this.polygons[i].flip()
this.plane && this.plane.flip()
this.front && this.front.invert()
this.back && this.back.invert()
let temp = this.front
this.front = this.back
this.back = temp
}
// Recursively remove all polygons in `polygons` that are inside this BSP
// tree.
clipPolygons(polygons: Polygon[]) {
if (!this.plane) return polygons.slice()
let front: Polygon[] = []
let back: Polygon[] = []
for (let i = 0; i < polygons.length; i++) {
this.plane.splitPolygon(polygons[i], front, back, front, back)
}
if (this.front) front = this.front.clipPolygons(front)
if (this.back) back = this.back.clipPolygons(back)
else back = []
return front.concat(back)
}
// Remove all polygons in this BSP tree that are inside the other BSP tree
// `bsp`.
clipTo(bsp: Node) {
this.polygons = bsp.clipPolygons(this.polygons)
if (this.front) this.front.clipTo(bsp)
if (this.back) this.back.clipTo(bsp)
}
// Return a list of all polygons in this BSP tree.
allPolygons() {
let polygons = this.polygons.slice()
if (this.front) polygons = polygons.concat(this.front.allPolygons())
if (this.back) polygons = polygons.concat(this.back.allPolygons())
return polygons
}
// Build a BSP tree out of `polygons`. When called on an existing tree, the
// new polygons are filtered down to the bottom of the tree and become new
// nodes there. Each set of polygons is partitioned using the first polygon
// (no heuristic is used to pick a good split).
build(polygons: Polygon[]) {
if (!polygons.length) return
if (!this.plane) this.plane = polygons[0].plane.clone()
let front: Polygon[] = []
let back: Polygon[] = []
for (let i = 0; i < polygons.length; i++) {
this.plane.splitPolygon(
polygons[i],
this.polygons,
this.polygons,
front,
back
)
}
if (front.length) {
if (!this.front) this.front = new Node()
this.front.build(front)
}
if (back.length) {
if (!this.back) this.back = new Node()
this.back.build(back)
}
}
static fromJSON = function (json: CSG) {
return CSG.fromPolygons(
json.polygons.map(
(p) =>
new Polygon(
p.vertices.map(
(v) => new Vertex(v.pos, v.normal, v.uv)
),
p.shared
)
)
)
}
}
export { CSG, Vertex, Vector, Polygon, Plane }
// Return a new CSG solid representing space in either this solid or in the
// solid `csg`. Neither this solid nor the solid `csg` are modified.
//
// A.union(B)
//
// +-------+ +-------+
// | | | |
// | A | | |
// | +--+----+ = | +----+
// +----+--+ | +----+ |
// | B | | |
// | | | |
// +-------+ +-------+
//
// Return a new CSG solid representing space in this solid but not in the
// solid `csg`. Neither this solid nor the solid `csg` are modified.
//
// A.subtract(B)
//
// +-------+ +-------+
// | | | |
// | A | | |
// | +--+----+ = | +--+
// +----+--+ | +----+
// | B |
// | |
// +-------+
//
// Return a new CSG solid representing space both this solid and in the
// solid `csg`. Neither this solid nor the solid `csg` are modified.
//
// A.intersect(B)
//
// +-------+
// | |
// | A |
// | +--+----+ = +--+
// +----+--+ | +--+
// | B |
// | |
// +-------+
//
|