Merge pull request #220 from martinRenou/fractals_forest

Add Fractals forest example

Author: martinRenou

examples/fractals_forest.ipynb

@@ -0,0 +1,90 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "364e2f77",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "from math import pi\n",
+    "from random import choice, uniform, randint\n",
+    "\n",
+    "from ipycanvas import Canvas, hold_canvas\n",
+    "from ipywidgets import Button\n",
+    "\n",
+    "\n",
+    "def draw_tree(canvas, start_x, start_y, length, angle, branch_width):\n",
+    "    canvas.begin_path()\n",
+    "    canvas.save()\n",
+    "    canvas.line_width = branch_width\n",
+    "    canvas.translate(start_x, start_y)\n",
+    "    canvas.rotate(angle * pi / 180)\n",
+    "    canvas.move_to(0, 0)\n",
+    "    canvas.line_to(0, -length)\n",
+    "\n",
+    "    if length > 25:\n",
+    "        canvas.stroke_style = '#c68a47'\n",
+    "    else:\n",
+    "        canvas.stroke_style = choice(['#559b37', '#379b4b', '#879b37'])\n",
+    "\n",
+    "    canvas.stroke()\n",
+    "\n",
+    "    if length < 10:\n",
+    "        canvas.restore()\n",
+    "        return\n",
+    "\n",
+    "    draw_tree(canvas, 0, -length, length * uniform(0.8, 0.9), angle + uniform(-1, 10), branch_width * 0.7)\n",
+    "    draw_tree(canvas, 0, -length, length * uniform(0.8, 0.9), angle + uniform(-10, 1), branch_width * 0.7)\n",
+    "    canvas.restore()\n",
+    "\n",
+    "canvas = Canvas()\n",
+    "\n",
+    "canvas.shadow_color = 'black'\n",
+    "canvas.shadow_offset_x = 1\n",
+    "canvas.shadow_offset_y = 0\n",
+    "canvas.shadow_blur = 3\n",
+    "canvas.line_cap = 'round'\n",
+    "\n",
+    "\n",
+    "def draw_random_forest(*args):\n",
+    "    global canvas\n",
+    "\n",
+    "    with hold_canvas(canvas):\n",
+    "        canvas.clear()\n",
+    "        for tree in range(randint(6, 10)):\n",
+    "            draw_tree(canvas, uniform(0, canvas.width), canvas.height, uniform(40, 70), uniform(-10, 10), uniform(8, 15))\n",
+    "        canvas.fill_style = '#559b37'\n",
+    "        canvas.fill_rect(0, canvas.height - 5, canvas.width, canvas.height)\n",
+    "\n",
+    "draw_random_forest()\n",
+    "\n",
+    "button = Button(description='Generate new forest')\n",
+    "button.on_click(draw_random_forest)\n",
+    "\n",
+    "display(canvas, button)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}