Question

我正在尝试提出一个迭代函数，为六边形网格生成xyz坐标。使用起始十六进制位置（简单来说就是0,0,0），我想计算每个连续“六边形”环的坐标，如下所示：

到目前为止，我设法想出的就是这个（javascript中的例子）：

var radius = 3
var xyz = [0,0,0];

// for each ring
for (var i = 0; i < radius; i++) {
    var tpRing = i*6;
    var tpVect = tpRing/3;
    // for each vector of ring
    for (var j = 0; j < 3; j++) {
        // for each tile in vector
        for(var k = 0; k < tpVect; k++) {
            xyz[0] = ???;
            xyz[1] = ???;
            xyz[2] = ???;
            console.log(xyz);
        }
    }
}

我知道每个环比前一个包含六个点，每个120°向量包含从中心开始的每个步骤的一个附加点。我也知道所有瓷砖x + y + z = 0。但是，如何生成遵循以下顺序的坐标列表？

    0, 0, 0

    0,-1, 1
    1,-1, 0
    1, 0,-1
    0, 1,-1
   -1, 1, 0
   -1, 0, 1

    0,-2, 2
    1,-2, 1
    2,-2, 0
    2,-1,-1
    2, 0,-2
    1, 1,-2
    0, 2,-2
   -1, 2,-1
   -2, 2, 0
   -2, 1, 1
   -2, 0, 2
   -1,-1, 2

Answer 1

另一种可能的解决方案，在 O（半径²）中运行，与 O（半径⁴）不同 > tehMick's solution（以很多风格为代价）是：

radius = 4
for r in range(radius):
    print "radius %d" % r
    x = 0
    y = -r
    z = +r
    print x,y,z
    for i in range(r):
        x = x+1
        z = z-1
        print x,y,z
    for i in range(r):
        y = y+1
        z = z-1
        print x,y,z
    for i in range(r):
        x = x-1
        y = y+1
        print x,y,z
    for i in range(r):
        x = x-1
        z = z+1
        print x,y,z
    for i in range(r):
        y = y-1
        z = z+1
        print x,y,z
    for i in range(r-1):
        x = x+1
        y = y-1
        print x,y,z

或写得更简洁：

radius = 4
deltas = [[1,0,-1],[0,1,-1],[-1,1,0],[-1,0,1],[0,-1,1],[1,-1,0]]
for r in range(radius):
    print "radius %d" % r
    x = 0
    y = -r
    z = +r
    print x,y,z
    for j in range(6):
        if j==5:
            num_of_hexas_in_edge = r-1
        else:
            num_of_hexas_in_edge = r
        for i in range(num_of_hexas_in_edge):
            x = x+deltas[j][0]
            y = y+deltas[j][1]
            z = z+deltas[j][2]            
            print x,y,z

它的灵感来自于六边形实际上位于六边形的外部，因此您可以找到其中1个点的坐标，然后通过移动其6个边来计算其他坐标。

Answer 2

不仅是x + y + z = 0，而且x，y和z的绝对值等于环的半径的两倍。这应该足以识别每个连续环上的每个六边形：

var radius = 4;
for(var i = 0; i < radius; i++)
{
    for(var j = -i; j <= i; j++)
    for(var k = -i; k <= i; k++)
    for(var l = -i; l <= i; l++)
        if(Math.abs(j) + Math.abs(k) + Math.abs(l) == i*2 && j + k + l == 0)
            console.log(j + "," + k + "," + l);
    console.log("");
}

Answer 3

这是一个有趣的谜题。

O（半径²）但是（希望）比Ofri's solution.更多样式我觉得可以生成坐标，就好像你是使用方向（移动）向量在环上“行走”，并且转弯相当于在移动向量周围移动零点。

这个版本还具有优于Eric's solution的优势，因为它永远不会触及无效坐标（Eric拒绝它们，但是这个甚至不必测试它们。）

# enumerate coords in rings 1..n-1; this doesn't work for the origin
for ring in range(1,4):
    # start in the upper right corner ...
    (x,y,z) = (0,-ring,ring)
    # ... moving clockwise (south-east, or +x,-z)
    move = [1,0,-1]         

    # each ring has six more coordinates than the last
    for i in range(6*ring):
        # print first to get the starting hex for this ring
        print "%d/%d: (%d,%d,%d) " % (ring,i,x,y,z)
        # then move to the next hex
        (x,y,z) = map(sum, zip((x,y,z), move))

        # when a coordinate has a zero in it, we're in a corner of
        # the ring, so we need to turn right
        if 0 in (x,y,z):
            # left shift the zero through the move vector for a
            # right turn
            i = move.index(0)
            (move[i-1],move[i]) = (move[i],move[i-1])

    print # blank line between rings

为python的序列切片提供三种欢呼。

Answer 4

好的，在尝试了两种选项之后，我已经确定了Ofri的解决方案，因为它更快一点，并且很容易提供初始偏移值。我的代码现在看起来像这样：

var xyz = [-2,2,0];
var radius = 16;
var deltas = [[1,0,-1],[0,1,-1],[-1,1,0],[-1,0,1],[0,-1,1],[1,-1,0]];
for(var i = 0; i < radius; i++) {
        var x = xyz[0];
        var y = xyz[1]-i;
        var z = xyz[2]+i;
        for(var j = 0; j < 6; j++) {
                for(var k = 0; k < i; k++) {
                        x = x+deltas[j][0]
                        y = y+deltas[j][1]
                        z = z+deltas[j][2]
                        placeTile([x,y,z]);
                }
        }
}

“placeTile”方法使用cloneNode复制预定义的svg元素，每个tile需要大约0.5ms才能执行，这已经足够了。非常感谢tehMick和Ofri的帮助！

JS

Answer 5

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');
ctx.textAlign = "center";

const radius = 20;
const altitude = Math.sqrt(3) * radius;
const total = 3;
for (let x = -total; x <= total; x++) {
    let y1 = Math.max(-total, -x-total);
    let y2 = Math.min(total, -x+total);
    for (let y = y1; y <= y2; y++) {
        let xx = x * altitude + Math.cos(1/3*Math.PI) * y * altitude;
        let yy = y * radius * 1.5;
        xx += canvas.width/2;
        yy += canvas.height/2;
        drawHex(xx, yy, radius);
        ctx.fillText(x+","+y, xx, yy);
    }
}

function drawHex(x, y, radius){
    ctx.beginPath();
    for(let a = 0; a < Math.PI*2; a+=Math.PI/3){
        let xx = Math.sin(a) * radius + x;
        let yy = Math.cos(a) * radius + y;
        if(a == 0) ctx.moveTo(xx, yy);
        else ctx.lineTo(xx, yy);
    }
    ctx.stroke();
}

<canvas id="canvas" width=250 height=250>

生成三角形/六边形坐标（xyz）

5 个答案: