例如,我有一个包含3个航路点的数组:
[ [ 526, 1573, 24 ], [ 2224, 809, -1546 ], [ 6869, 96, -3074 ] ]
我也知道我想休息一下,直到到达第一个和最后一个航点之间的n
次。所以最后我想要一个n
点的数组。
如何在JS中找到这些n
个静止点?
谢谢!
编辑:请注意,这不是单个对象!想象每个轴是一个人。他们必须在相同的时间停止相同的时间,但不必明显地在同一地点。
答案 0 :(得分:1)
您要使用线性插值。
一个简单的例子:
const POINTS = [ [ 526, 1573, 24 ], [ 2224, 809, -1546 ], [ 6869, 96, -3074 ] ];
const N = 10;
function getDistance(point1, point2) {
// speed in 3d space is mutated according only to the X distance,
// to keep speed constant in X dimension
return Math.abs(point1[0] - point2[0]);
}
function go(points, n) {
const pointDistances = points.slice(1).map((point, index) => getDistance(points[index], point));
const fullDistance = pointDistances.reduce((sum, distance) => sum + distance, 0);
const distancePerSection = fullDistance / n;
return points.slice(1)
.reduce((last, point, index) => {
const thisDistance = pointDistances[index];
const numRestPoints = Math.max(0, Math.floor(thisDistance / distancePerSection) - 1);
if (!numRestPoints) {
return last.concat([point]);
}
const thisYVector = point[1] - points[index][1];
const thisZVector = point[2] - points[index][2];
return last.concat(new Array(numRestPoints).fill(0)
.reduce((section, item, restIndex) => {
return section.concat([[
points[index][0] + (restIndex + 1) * distancePerSection,
points[index][1] + (restIndex + 1) * thisYVector * distancePerSection / thisDistance,
points[index][2] + (restIndex + 1) * thisZVector * distancePerSection / thisDistance
]]);
}, [])
.concat([point])
);
}, points.slice(0, 1));
}
function test() {
const result = go(POINTS, N);
if (result.length !== N) {
throw new Error('Must be N length');
}
if (!result[0].every((value, index) => value === POINTS[0][index])) {
throw new Error('Doesn\'t start at the first point');
}
if (!result[N - 1].every((value, index) => value === POINTS[POINTS.length - 1][index])) {
throw new Error('Doesn\'t end at the last point');
}
if (!POINTS.slice(1, N - 1).every(point =>
result.some(resultPoint => resultPoint.every((value, index) => value === point[index]))
)) {
throw new Error('Doesn\'t go through every provided point');
}
console.log(result.slice(1).map((point, index) => getDistance(point, result[index])));
console.log('The result passed the tests!');
console.log(JSON.stringify(result, null, 2));
}
test();
我基本上要遍历点列表,并确定它们之间是否应存在任何休息点,如果有的话,请插入它们。
如果您想进一步澄清,请发表评论!
答案 1 :(得分:0)
我现在也通过线性插值解决了这个问题:
我的解决方案:
var waypoints = [[526,1573,24],[2224,809,-1546],[6869,96,-3074]];
var pauses = 20;
generateWaypopints();
function generateWaypopints(){
var newWaypoints = [];
var progressAtMainPoints = 1 / (waypoints.length - 1)
var pausesBetweenWaypoints = pauses * progressAtMainPoints;
var progressAtPauses = 1 / pausesBetweenWaypoints;
newWaypoints.push(waypoints[0]);
var sector = 0;
var pausesInSector = 0;
for(var i = 0; i < pauses; i++){
var progress = progressAtPauses * (pausesInSector + 1)
var x = Math.round(waypoints[sector][0] + (waypoints[sector + 1][0] - waypoints[sector][0]) * progress);
var y = Math.round(waypoints[sector][1] + (waypoints[sector + 1][1] - waypoints[sector][1]) * progress);
var z = Math.round(waypoints[sector][2] + (waypoints[sector + 1][2] - waypoints[sector][2]) * progress);
if(progress >= 1){
sector++;
pausesInSector = 0;
}else
pausesInSector++;
newWaypoints.push([x,y,z]);
}
console.log(newWaypoints);
return newWaypoints;
}