从3个给定点定向3d平面

Question

给定3个动态点，定位平面以使其与所有3个点相交的最佳方法是什么？

我正在使用Three.js

Answer 1

创建几何体。为每个点添加顶点，然后创建一个面。例如：

var geometry = new THREE.Geometry();
geometry.vertices.push(new THREE.Vector3(0,0,0));
geometry.vertices.push(new THREE.Vector3(1,1,0));
geometry.vertices.push(new THREE.Vector3(1,-1,0));
geometry.faces.push( new THREE.Face3( 0, 1, 2 ) );
geometry.dynamic = true;
var shapeMesh = new THREE.Mesh(geometry, material);
scene.add(shapeMesh);

每次更改几何图形时，请务必让three.js知道：

geometry.verticesNeedUpdate = true;
geometry.elementsNeedUpdate = true;

Answer 2

要获取矢量的方向以定向平面，请计算三角形中任意两边的叉积

所以，如果你的积分是a，b，c

side1 = subVectors (a, b);
side2 = subVectors (a, c);
planeNormal = crossVectors (side1, side2);