🔺 三角龙分形Draw a Triangle Dragon Fractal
绘制三角龙（terdragon）曲线：每条线段换成三段、转 120°，是海威龙的三角变体，可调迭代与颜色，导出 PNG。Draw the triangle dragon (terdragon): every segment becomes three with 120° turns, a triangular variant of the Heighway dragon. Set iterations and colours; export PNG.
使用说明与常见问题How-to & FAQ
「三角龙分形」是什么？What is the Draw a Triangle Dragon Fractal tool?
绘制三角龙（terdragon）曲线：每条线段换成三段、转 120°，是海威龙的三角变体，可调迭代与颜色，导出 PNG。Draw the triangle dragon (terdragon): every segment becomes three with 120° turns, a triangular variant of the Heighway dragon. Set iterations and colours; export PNG.
如何使用「三角龙分形」？How do I use the Draw a Triangle Dragon Fractal tool?
在「三角龙分形」中，按需设置「宽度」、「高度」、「边距」、「线宽」、「迭代次数」等选项，然后点击「绘制」、「下载 PNG」按钮即可。Set the canvas "Width" and "Height", the "Padding" around the drawing and the "Line width", choose how many "Iterations" to draw, pick the "Background", "Line" and "Fill" colours, then click "Draw". "Download PNG" saves the picture at the canvas size.
三角龙和海威龙有何不同？How does this differ from the Heighway dragon?
海威龙每步把线段换成两段、转 90°；三角龙（terdragon）用 L 系统 F → F+F-F，每步换成三段、转 120°，轮廓更接近三角形。和海威龙一样，它从不重复走同一条边（顶点可以相碰），多次迭代后铺满一块区域。The Heighway dragon replaces each segment with two and turns 90°; the terdragon uses the L-system F → F+F-F, replacing each segment with three and turning 120°, so the outline is more triangular. Like the Heighway dragon it never runs along the same edge twice (corners may touch) and fills a region after many iterations.
迭代建议？Suggested iterations?
线段数是 3^n：6 次（默认）729 段，10 次（上限）59049 段，已经很密。There are 3^n segments: 729 at the default 6 and 59,049 at the maximum 10, which is already very dense.
有哪些选项可以调整？What options can I adjust?
「三角龙分形」的设置：「宽度」默认 512，范围 64–2048；「高度」默认 512，范围 64–2048；「边距」默认 20，范围 0–256；「线宽」默认 2，范围 0.5–40；「迭代次数」默认 6，范围 1–10；「背景」默认 #ffffff；「线条」默认 #1e3a8a。改动任一选项后结果会按新设置重新生成。Settings in the Draw a Triangle Dragon Fractal — "Width" default 512, range 64–2048; "Height" default 512, range 64–2048; "Padding" default 20, range 0–256; "Line width" default 2, range 0.5–40; "Iterations" default 6, range 1–10; "Background" default #ffffff; "Line" default #1e3a8a. Changing any option regenerates the result with the new setting.
「三角龙分形」免费吗？需要注册吗？Is the Draw a Triangle Dragon Fractal free? Do I need an account?
「三角龙分形」完全免费，无需注册或安装，打开网页即可使用，手机和电脑都能用；输入的内容只在你的浏览器本地处理。The Draw a Triangle Dragon Fractal is completely free with no sign-up or install and works on phones and desktops; what you enter is processed only in your browser.