У меня могло бы быть решение. Не использовали three.js через некоторое время, поэтому не уверен, что это самое элегантное решение. Я начал с Shapes Example, так как он показывает:
- Как построить путь процедурно (используя команды, которые также обрабатывать кривые)
- Как извлечь точки из такого пути
Так что я ве разделить проблему на:
- Генерирование пути
- обходе пути, и я nterpolation (положение и вращение)
Генерирование путь Я повторно закругленный определение прямоугольника, который выглядит похожим на часть вашего экрана.
var roundedRectShape = new THREE.Shape();
(function roundedRect(ctx, x, y, width, height, radius){
ctx.moveTo(x, y + radius);
ctx.lineTo(x, y + height - radius);
ctx.quadraticCurveTo(x, y + height, x + radius, y + height);
ctx.lineTo(x + width - radius, y + height) ;
ctx.quadraticCurveTo(x + width, y + height, x + width, y + height - radius);
ctx.lineTo(x + width, y + radius);
ctx.quadraticCurveTo(x + width, y, x + width - radius, y);
ctx.lineTo(x + radius, y);
ctx.quadraticCurveTo(x, y, x, y + radius);
})(roundedRectShape, 0, 0, 200, 200, 20);
Ваш путь не может быть прямоугольник с закругленными углами, но доступные типы кривых функций (quadraticCurveTo, bezierCurveTo, splineThru) действительно полезны.
Другая идея, которая приходит на ум, - использовать скрипт Ruby для экспорта координат пути из Sketchup в three.js. Либо вы пишете это с нуля, либо используете существующие скрипты. Вот one легко найти в google.
обходе пути
К счастью Three.js уже реализует это через путь, где getPoint(t)
-й т представляет собой число от 0.0 до 1.0, представляющего обхода на пути. Таким образом, получение позиции тривиально, как получение следующей интерполированной позиции на пути. Тогда это просто вопрос использования Math.atan2()
, чтобы получить вращение:
t = (t + s)%1.0;//increment t while maintaining it between 0.0 and 1.0
var p = path.getPoint(t);//point at t
var pn = path.getPoint((t+s)%1.0);//point at next t iteration
if(p != null && pn != null){
//move to current position
arrow.position.x = p.x;
arrow.position.y = p.y;
//get orientation based on next position
arrow.rotation.z = Math.atan2(pn.y-p.y,pn.x-p.x);
}
В заключении сильфона простой пример (с использованием кубы вместо формы стрелки) для иллюстрации генерирования и перемещение по пути в три.JS основанные на примере фигуры:
<!DOCTYPE html>
<html lang="en">
<head>
<title>path interpolation</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
<style>
body {
font-family: Monospace;
background-color: #f0f0f0;
margin: 0px;
overflow: hidden;
}
</style>
</head>
<body>
<canvas id="debug" style="position:absolute; left:100px"></canvas>
<script src="../build/three.min.js"></script>
<script src="js/libs/stats.min.js"></script>
<script>
var container, stats;
var camera, scene, renderer;
var text, plane;
var targetRotation = 0;
var targetRotationOnMouseDown = 0;
var mouseX = 0;
var mouseXOnMouseDown = 0;
var windowHalfX = window.innerWidth/2;
var windowHalfY = window.innerHeight/2;
init();
animate();
var t = 0.0;//traversal on path
var s = 0.001;//speed of traversal
var arrow;//mesh to move/rotate on path
var path;//Path object to traverse
function init() {
container = document.createElement('div');
document.body.appendChild(container);
camera = new THREE.PerspectiveCamera(50, window.innerWidth/window.innerHeight, 1, 1000);
camera.position.set(0, 150, 500);
scene = new THREE.Scene();
parent = new THREE.Object3D();
parent.position.y = 50;
scene.add(parent);
arrow = new THREE.Mesh(new THREE.CubeGeometry(20,10,10),new THREE.MeshBasicMaterial({color: 0x009900}));
parent.add(arrow);
//this is helpful as a visual aid but not crucial
function addShape(shape, extrudeSettings, color, x, y, z, rx, ry, rz, s) {
var points = shape.createPointsGeometry();
var spacedPoints = shape.createSpacedPointsGeometry(50);
// transparent line from equidistance sampled points
var line = new THREE.Line(spacedPoints, new THREE.LineBasicMaterial({ color: color, opacity: 0.2 }));
line.rotation.set(rx, ry, rz);
parent.add(line);
// equidistance sampled points
var pgeo = spacedPoints.clone();
var particles2 = new THREE.ParticleSystem(pgeo, new THREE.ParticleBasicMaterial({ color: color, size: 2, opacity: 0.5 }));
particles2.rotation.set(rx, ry, rz);
parent.add(particles2);
}
// Rounded rectangle
//generating the path and populating it is crucial tough
var roundedRectShape = new THREE.Shape();
(function roundedRect(ctx, x, y, width, height, radius){
ctx.moveTo(x, y + radius);
ctx.lineTo(x, y + height - radius);
ctx.quadraticCurveTo(x, y + height, x + radius, y + height);
ctx.lineTo(x + width - radius, y + height) ;
ctx.quadraticCurveTo(x + width, y + height, x + width, y + height - radius);
ctx.lineTo(x + width, y + radius);
ctx.quadraticCurveTo(x + width, y, x + width - radius, y);
ctx.lineTo(x + radius, y);
ctx.quadraticCurveTo(x, y, x, y + radius);
})(roundedRectShape, 0, 0, 200, 200, 20);
path = roundedRectShape;
var extrudeSettings = { amount: 20 }; // bevelSegments: 2, steps: 2 , bevelSegments: 5, bevelSize: 8, bevelThickness:5
extrudeSettings.bevelEnabled = true;
extrudeSettings.bevelSegments = 2;
extrudeSettings.steps = 2;
addShape(roundedRectShape, extrudeSettings, 0x000000, -150, 150, 0, 0, 0, 0, 1);
renderer = new THREE.WebGLRenderer({ antialias: true });
renderer.setSize(window.innerWidth, window.innerHeight);
container.appendChild(renderer.domElement);
stats = new Stats();
stats.domElement.style.position = 'absolute';
stats.domElement.style.top = '0px';
container.appendChild(stats.domElement);
document.addEventListener('mousedown', onDocumentMouseDown, false);
document.addEventListener('touchstart', onDocumentTouchStart, false);
document.addEventListener('touchmove', onDocumentTouchMove, false);
//
window.addEventListener('resize', onWindowResize, false);
}
function onWindowResize() {
windowHalfX = window.innerWidth/2;
windowHalfY = window.innerHeight/2;
camera.aspect = window.innerWidth/window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
//
function onDocumentMouseDown(event) {
event.preventDefault();
document.addEventListener('mousemove', onDocumentMouseMove, false);
document.addEventListener('mouseup', onDocumentMouseUp, false);
document.addEventListener('mouseout', onDocumentMouseOut, false);
mouseXOnMouseDown = event.clientX - windowHalfX;
targetRotationOnMouseDown = targetRotation;
}
function onDocumentMouseMove(event) {
mouseX = event.clientX - windowHalfX;
targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.02;
}
function onDocumentMouseUp(event) {
document.removeEventListener('mousemove', onDocumentMouseMove, false);
document.removeEventListener('mouseup', onDocumentMouseUp, false);
document.removeEventListener('mouseout', onDocumentMouseOut, false);
}
function onDocumentMouseOut(event) {
document.removeEventListener('mousemove', onDocumentMouseMove, false);
document.removeEventListener('mouseup', onDocumentMouseUp, false);
document.removeEventListener('mouseout', onDocumentMouseOut, false);
}
function onDocumentTouchStart(event) {
if (event.touches.length == 1) {
event.preventDefault();
mouseXOnMouseDown = event.touches[ 0 ].pageX - windowHalfX;
targetRotationOnMouseDown = targetRotation;
}
}
function onDocumentTouchMove(event) {
if (event.touches.length == 1) {
event.preventDefault();
mouseX = event.touches[ 0 ].pageX - windowHalfX;
targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.05;
}
}
//
function animate() {
requestAnimationFrame(animate);
render();
stats.update();
}
function render() {
t = (t + s)%1.0;//increment t while maintaining it between 0.0 and 1.0
var p = path.getPoint(t);//point at t
var pn = path.getPoint((t+s)%1.0);//point at next t iteration
if(p != null && pn != null){
//move to current position
arrow.position.x = p.x;
arrow.position.y = p.y;
//get orientation based on next position
arrow.rotation.z = Math.atan2(pn.y-p.y,pn.x-p.x);
}
parent.rotation.y += (targetRotation - parent.rotation.y) * 0.05;
renderer.render(scene, camera);
}
</script>
</body>
</html>
Думал бы добавить работоспособный фрагмент прямо на этой странице:
var container;
var camera, scene, renderer;
var text, plane;
var targetRotation = 0;
var targetRotationOnMouseDown = 0;
var mouseX = 0;
var mouseXOnMouseDown = 0;
var windowHalfX = window.innerWidth/2;
var windowHalfY = window.innerHeight/2;
init();
animate();
var t = 0.0;//traversal on path
var s = 0.001;//speed of traversal
var arrows;//mesh to move/rotate on path
var path;//Path object to traverse
function init() {
container = document.createElement('div');
document.body.appendChild(container);
camera = new THREE.PerspectiveCamera(50, window.innerWidth/window.innerHeight, 1, 1000);
camera.position.set(0, 150, 500);
scene = new THREE.Scene();
parent = new THREE.Object3D();
parent.position.y = 50;
scene.add(parent);
arrows = [];
for(var i = 0 ; i < 50; i++){
arrows[i] = new THREE.Mesh(new THREE.CubeGeometry(10,5,5),new THREE.MeshBasicMaterial({color: 0x009900}));
parent.add(arrows[i]);
}
//this is helpful as a visual aid but not crucial
function addShape(shape, extrudeSettings, color, x, y, z, rx, ry, rz, s) {
var points = shape.createPointsGeometry();
var spacedPoints = shape.createSpacedPointsGeometry(50);
// transparent line from equidistance sampled points
var line = new THREE.Line(spacedPoints, new THREE.LineBasicMaterial({ color: color, opacity: 0.2 }));
line.rotation.set(rx, ry, rz);
parent.add(line);
// equidistance sampled points
var pgeo = spacedPoints.clone();
var particles2 = new THREE.ParticleSystem(pgeo, new THREE.ParticleBasicMaterial({ color: color, size: 2, opacity: 0.5 }));
particles2.rotation.set(rx, ry, rz);
parent.add(particles2);
}
// Rounded rectangle
//generating the path and populating it is crucial tough
var roundedRectShape = new THREE.Shape();
(function roundedRect(ctx, x, y, width, height, radius){
ctx.moveTo(x, y + radius);
ctx.lineTo(x, y + height - radius);
ctx.quadraticCurveTo(x, y + height, x + radius, y + height);
ctx.lineTo(x + width - radius, y + height) ;
ctx.quadraticCurveTo(x + width, y + height, x + width, y + height - radius);
ctx.lineTo(x + width, y + radius);
ctx.quadraticCurveTo(x + width, y, x + width - radius, y);
ctx.lineTo(x + radius, y);
ctx.quadraticCurveTo(x, y, x, y + radius);
})(roundedRectShape, 0, 0, 200, 200, 20);
path = roundedRectShape;
var extrudeSettings = { amount: 20 }; // bevelSegments: 2, steps: 2 , bevelSegments: 5, bevelSize: 8, bevelThickness:5
extrudeSettings.bevelEnabled = true;
extrudeSettings.bevelSegments = 2;
extrudeSettings.steps = 2;
addShape(roundedRectShape, extrudeSettings, 0x000000, -150, 150, 0, 0, 0, 0, 1);
renderer = new THREE.WebGLRenderer({ antialias: true });
renderer.setSize(window.innerWidth, window.innerHeight);
container.appendChild(renderer.domElement);
document.addEventListener('mousedown', onDocumentMouseDown, false);
document.addEventListener('touchstart', onDocumentTouchStart, false);
document.addEventListener('touchmove', onDocumentTouchMove, false);
//
window.addEventListener('resize', onWindowResize, false);
}
function onWindowResize() {
windowHalfX = window.innerWidth/2;
windowHalfY = window.innerHeight/2;
camera.aspect = window.innerWidth/window.innerHeight;
camera.updateProjectionMatrix();
renderer.setSize(window.innerWidth, window.innerHeight);
}
//
function onDocumentMouseDown(event) {
event.preventDefault();
document.addEventListener('mousemove', onDocumentMouseMove, false);
document.addEventListener('mouseup', onDocumentMouseUp, false);
document.addEventListener('mouseout', onDocumentMouseOut, false);
mouseXOnMouseDown = event.clientX - windowHalfX;
targetRotationOnMouseDown = targetRotation;
}
function onDocumentMouseMove(event) {
mouseX = event.clientX - windowHalfX;
targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.02;
}
function onDocumentMouseUp(event) {
document.removeEventListener('mousemove', onDocumentMouseMove, false);
document.removeEventListener('mouseup', onDocumentMouseUp, false);
document.removeEventListener('mouseout', onDocumentMouseOut, false);
}
function onDocumentMouseOut(event) {
document.removeEventListener('mousemove', onDocumentMouseMove, false);
document.removeEventListener('mouseup', onDocumentMouseUp, false);
document.removeEventListener('mouseout', onDocumentMouseOut, false);
}
function onDocumentTouchStart(event) {
if (event.touches.length == 1) {
event.preventDefault();
mouseXOnMouseDown = event.touches[ 0 ].pageX - windowHalfX;
targetRotationOnMouseDown = targetRotation;
}
}
function onDocumentTouchMove(event) {
if (event.touches.length == 1) {
event.preventDefault();
mouseX = event.touches[ 0 ].pageX - windowHalfX;
targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.05;
}
}
//
function animate() {
requestAnimationFrame(animate);
render();
}
function render() {
t = (t + s)%1.0;//increment t while maintaining it between 0.0 and 1.0 - could map mouse x position/window width for fun :)
\t \t \t \t for(var i = 0 ; i < 50; i++){//for each box
\t \t \t \t \t var ti = ((i/50.0)+t)%1.0;//compute the traversval including each box's own offset on the path
\t \t \t \t \t
\t \t \t \t \t var p = path.getPoint(ti);//point at t
\t \t \t \t \t var pn = path.getPoint((ti+s)%1.0);//point at next t iteration
\t \t \t \t
\t \t \t \t \t if(p != null && pn != null){
\t \t \t \t \t \t //move to current position
\t \t \t \t \t \t arrows[i].position.x = p.x;
\t \t \t \t \t \t arrows[i].position.y = p.y;
\t \t \t \t \t \t //get orientation based on next position
\t \t \t \t \t \t arrows[i].rotation.z = Math.atan2(pn.y-p.y,pn.x-p.x);
\t \t \t \t \t
\t \t \t \t \t }
\t \t \t \t }
parent.rotation.y += (targetRotation - parent.rotation.y) * 0.05;
renderer.render(scene, camera);
}
body {
font-family: Monospace;
background-color: #f0f0f0;
margin: 0px;
overflow: hidden;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/three.js/r71/three.min.js"></script>
Связанный: http://stackoverflow.com/questions/11179327/orient-objects-rotation-to-a-spline-point-tangent-in-three-js/11181366 # 11181366 – WestLangley