Three.js:将圆柱体旋转到 Vector3 方向 [英] Three.js: Rotate Cylinder into Vector3 direction

问题描述

我已经搜索过了，但没有找到任何有用的内容:

I've already searched, but didn't find anything that helps:

我得到了一个向量和一个 CylinderGeometry 网格.我想实现，圆柱面向向量显示的点.作为输入，我得到了一个位置 (c) 和一个方向 (m)(就像一个直线方程:y = mx + c):

I got an vector and a CylinderGeometry Mesh. I want to acchieve, that the cylinder is facing the point where the vector is showing. As input I got a position (c) and a direction (m) (like a line equation: y = mx + c):

function draw (m,c, _color) {
  //... create the geometry and mesh
  // set the position
  line.position.x = c.x;
  line.position.y = c.y;
  line.position.z = c.z;

  // i've tried something like this:
  line.lookAt(c.add(m));

  //.. and add to scene
}

但看起来方向与我想要实现的方向正好相反.

But it looks like the direction is the direct opposite of what I want to acchieve.

我也尝试过翻译之类的东西:

I've also tried stuff like translation:

geometry.applyMatrix(new THREE.Matrix4().makeTranslation(0, length/2, 0));

并尝试像 line.rotation.x = direction.angleTo(vec3(1,0,0))* 180/Math.PI; 那样手动获取旋转.但没有一个像我需要的那样工作.

and tried to get the rotation manually like line.rotation.x = direction.angleTo(vec3(1,0,0))* 180 / Math.PI;. But none of them worked like I needed.

推荐答案

这对我有用:

  // Make the geometry (of "distance" length)
  var geometry = new THREE.CylinderGeometry( 0.6, 0.6, distance, 8, 1, true );
  // shift it so one end rests on the origin
  geometry.applyMatrix( new THREE.Matrix4().makeTranslation( 0, distance / 2, 0 ) );
  // rotate it the right way for lookAt to work
  geometry.applyMatrix( new THREE.Matrix4().makeRotationX( THREE.Math.degToRad( 90 ) ) );
  // Make a mesh with the geometry
  var mesh = new THREE.Mesh( geometry, material );
  // Position it where we want
  mesh.position.copy( from.sceneObject.position );
  // And make it point to where we want
  mesh.lookAt( to.sceneObject.position );

这篇关于Three.js:将圆柱体旋转到 Vector3 方向的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！