Three.js 如何将BufferGeometryUtils.js声明为three.d.ts

我不需要重构所有代码来提高性能。我在three.js示例目录中找到了BufferGeometryUtils，它支持将现有几何体转换为缓冲区几何体。我的问题是如何向three.d.ts声明此函数？ BufferGeometryUtils.js的源代码：

/**
 * @author spite / http://www.clicktorelease.com/
 * @author mrdoob / http://mrdoob.com/
 */

THREE.BufferGeometryUtils = {

fromGeometry: function geometryToBufferGeometry( geometry, settings ) {

    if ( geometry instanceof THREE.BufferGeometry ) {

        return geometry;

    }

    settings = settings || { 'vertexColors': THREE.NoColors };

    var vertices = geometry.vertices;
    var faces = geometry.faces;
    var faceVertexUvs = geometry.faceVertexUvs;
    var vertexColors = settings.vertexColors;
    var hasFaceVertexUv = faceVertexUvs[ 0 ].length > 0;

    var bufferGeometry = new THREE.BufferGeometry();

    bufferGeometry.attributes = {

        position: {
            itemSize: 3,
            array: new Float32Array( faces.length * 3 * 3 )
        },
        normal: {
            itemSize: 3,
            array: new Float32Array( faces.length * 3 * 3 )
        }

    }

    var positions = bufferGeometry.attributes.position.array;
    var normals = bufferGeometry.attributes.normal.array;

    if ( vertexColors !== THREE.NoColors ) {

        bufferGeometry.attributes.color = {
            itemSize: 3,
            array: new Float32Array( faces.length * 3 * 3 )
        };

        var colors = bufferGeometry.attributes.color.array;

    }

    if ( hasFaceVertexUv === true ) {

        bufferGeometry.attributes.uv = {
            itemSize: 2,
            array: new Float32Array( faces.length * 3 * 2 )
        };

        var uvs = bufferGeometry.attributes.uv.array;

    }

    var i2 = 0, i3 = 0;

    for ( var i = 0; i < faces.length; i ++ ) {

        var face = faces[ i ];

        var a = vertices[ face.a ];
        var b = vertices[ face.b ];
        var c = vertices[ face.c ];

        positions[ i3     ] = a.x;
        positions[ i3 + 1 ] = a.y;
        positions[ i3 + 2 ] = a.z;

        positions[ i3 + 3 ] = b.x;
        positions[ i3 + 4 ] = b.y;
        positions[ i3 + 5 ] = b.z;

        positions[ i3 + 6 ] = c.x;
        positions[ i3 + 7 ] = c.y;
        positions[ i3 + 8 ] = c.z;

        var na = face.vertexNormals[ 0 ];
        var nb = face.vertexNormals[ 1 ];
        var nc = face.vertexNormals[ 2 ];

        normals[ i3     ] = na.x;
        normals[ i3 + 1 ] = na.y;
        normals[ i3 + 2 ] = na.z;

        normals[ i3 + 3 ] = nb.x;
        normals[ i3 + 4 ] = nb.y;
        normals[ i3 + 5 ] = nb.z;

        normals[ i3 + 6 ] = nc.x;
        normals[ i3 + 7 ] = nc.y;
        normals[ i3 + 8 ] = nc.z;

        if ( vertexColors === THREE.FaceColors ) {

            var fc = face.color;

            colors[ i3     ] = fc.r;
            colors[ i3 + 1 ] = fc.g;
            colors[ i3 + 2 ] = fc.b;

            colors[ i3 + 3 ] = fc.r;
            colors[ i3 + 4 ] = fc.g;
            colors[ i3 + 5 ] = fc.b;

            colors[ i3 + 6 ] = fc.r;
            colors[ i3 + 7 ] = fc.g;
            colors[ i3 + 8 ] = fc.b;

        } else if ( vertexColors === THREE.VertexColors ) {

            var vca = face.vertexColors[ 0 ];
            var vcb = face.vertexColors[ 1 ];
            var vcc = face.vertexColors[ 2 ];

            colors[ i3     ] = vca.r;
            colors[ i3 + 1 ] = vca.g;
            colors[ i3 + 2 ] = vca.b;

            colors[ i3 + 3 ] = vcb.r;
            colors[ i3 + 4 ] = vcb.g;
            colors[ i3 + 5 ] = vcb.b;

            colors[ i3 + 6 ] = vcc.r;
            colors[ i3 + 7 ] = vcc.g;
            colors[ i3 + 8 ] = vcc.b;

        }

        if ( hasFaceVertexUv === true ) {

            var uva = faceVertexUvs[ 0 ][ i ][ 0 ];
            var uvb = faceVertexUvs[ 0 ][ i ][ 1 ];
            var uvc = faceVertexUvs[ 0 ][ i ][ 2 ];

            uvs[ i2     ] = uva.x;
            uvs[ i2 + 1 ] = uva.y;

            uvs[ i2 + 2 ] = uvb.x;
            uvs[ i2 + 3 ] = uvb.y;

            uvs[ i2 + 4 ] = uvc.x;
            uvs[ i2 + 5 ] = uvc.y;

        }

        i3 += 9;
        i2 += 6;

    }

    bufferGeometry.computeBoundingSphere();

    return bufferGeometry;

}

}

/**
*@author/http://www.clicktorelease.com/
*@author mrdoob/http://mrdoob.com/
*/
三个缓冲区几何公差={
fromGeometry：函数geometryToBufferGeometry（几何、设置）{
if（三个缓冲几何体的几何体实例）{
返回几何；
}
设置=设置| |{“顶点颜色”：三种颜色}；
var顶点=geometry.vertices；
var faces=geometry.faces；
var faceVertexUvs=几何体。faceVertexUvs；
var vertexColors=settings.vertexColors；
var hasFaceVertexUv=faceVertexUvs[0]。长度>0；
var bufferGeometry=new THREE.bufferGeometry（）；
bufferGeometry.attributes={
职位：{
项目规模：3，
数组：新Float32Array（faces.length*3*3）
},
正常：{
项目规模：3，
数组：新Float32Array（faces.length*3*3）
}
}
var positions=bufferGeometry.attributes.position.array；
var normals=bufferGeometry.attributes.normal.array；
if（顶点颜色！==3.NoColors）{
bufferGeometry.attributes.color={
项目规模：3，
数组：新Float32Array（faces.length*3*3）
};
var colors=bufferGeometry.attributes.color.array；
}
如果（hasFaceVertexUv==真）{
bufferGeometry.attributes.uv={
项目规模：2，
数组：新Float32Array（faces.length*3*2）
};
var uvs=bufferGeometry.attributes.uv.array；
}
var i2=0，i3=0；
对于（变量i=0；i

假设您已经拥有了，您可以扩展声明以包括附加的

缓冲区几何体，如下所示：

declare module THREE {
    export class GeometryBufferUtils {
        fromGeometry(geometry, settings) : any;
    }
}

var bufferUtils = new THREE.GeometryBufferUtils();
var example = bufferUti

在本例中，我刚刚用一个名为
GeometryBufferUtils
的新类扩展了现有的
THREE
模块声明-然后可以添加每个方法的定义-包括任何相关的类型信息

我不能在这里发布整个定义，因为答案长度是有限制的，但您应该能够从这个示例开始，并将其扩展到您想要的功能。您还可以收紧定义，在上面的示例中，这些定义非常松散（即参数当前为
any
type，但您可以这样键入它们：

fromGeometry(geometry: THREE.BufferGeometry, settings) : THREE.BufferGeometry;