这实际上是我在stackoverflow上的第一个问题 :)
首先,我想说我是编程新手,想要了解一些语法。基本上,我正在按照codetrain的教程创建面向对象的分形树,我想知道如何使它更加“三维” ,一种方法是通过旋转向量来实现。我一直在寻找潜在的解决方案来旋转下面的向量以在3D空间中使用。codetrain使用的示例是创建一个方向向量:direction = p5.Vector.Sub(this.begin, this.end)。然后他使用代码direction.rotate(45)。我意识到你不能写direction.rotateY(45)。从p5.js语法中我看到.rotate()只能用于2D向量。因此,是否有某种语法我忽略了可以根据以下代码将该向量在3D空间内旋转?
这是草图的代码。Branch类控制树的构造,branchA和branchB函数是可能添加一些旋转的地方。
var tree = [];
var leaves = [];
var count = 0;
function setup() {
createCanvas(windowWidth, windowHeight, WEBGL);
angleMode(DEGREES)
var randomangle = random(0, 90)
var randomMinusAngle = random(0, -90)
var a = createVector(0, 0, 0);
var b = createVector(0, -100, 0);
var root = new Branch(a, b);
tree[0] = root;
}
//INPUT.
function mousePressed() {
for (var i = tree.length - 1; i >= 0; i--) {
if (!tree[i].finished) {
tree.push(tree[i].branchA())
tree.push(tree[i].branchB())
}
tree[i].finished = true;
}
count++
if (count === 8) {
for (var i = 0; i < tree.length; i++) {
if (!tree[i].finished) {
var leaf = tree[i].end.copy();
leaves.push(leaf);
}
}
}
}
function draw() {
background(51);
//orbitControl();
rotateY(frameCount);
translate(0, 200, 0);
for (var i = 0; i < tree.length; i++) {
tree[i].show();
tree[i].rotateBranches();
//tree[i].jitter();
}
//LEAVES
for (var i = 0; i < leaves.length; i++) { //should make the leaves an object in new script.
fill(255, 0, 100);
noStroke();
ellipse(leaves[i].x, leaves[i].y, 8, 8);
}
}
function Branch(begin, end) {
this.begin = begin;
this.end = end;
//bool to check whether it has finished spawning branch.
this.finishedGrowing = false;
this.show = function() {
stroke(255);
line(this.begin.x, this.begin.y, this.begin.z, this.end.x, this.end.y, this.end.z);
}
//var rotateValue = random(0, 45)
this.branchA = function() {
var direction = p5.Vector.sub(this.end, this.begin);
direction.rotate(45)
direction.mult(0.67);
var newEnd = p5.Vector.add(this.end, direction);
var randomss = p5.Vector.random3D(this.end, newEnd)
var b = new Branch(this.end, newEnd);
return b;
}
this.branchB = function() {
var direction = p5.Vector.sub(this.end, this.begin)
direction.rotate(-15);
direction.mult(0.67);
var newEnd = p5.Vector.add(this.end, direction);
var b = new Branch(this.end, newEnd);
return b;
}
this.rotateBranches = function() {
// TODO
}
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/p5.js/1.3.1/p5.min.js"></script>