Merge pull request #185 from ondravondra/clockexample

added simple clock to the examples

Author: martinRenou

examples/clock.ipynb

@@ -0,0 +1,164 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "jupyter": {
+     "source_hidden": true
+    }
+   },
+   "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "31f9b1480ccd4389a39a82ac519b436c",
+       "version_major": 2,
+       "version_minor": 0
+      },
+      "text/plain": [
+       "Canvas(height=250, width=250)"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "from ipycanvas import Canvas, hold_canvas\n",
+    "import numpy as np\n",
+    "\n",
+    "CLOCK_RADIUS = 100\n",
+    "\n",
+    "canvas = Canvas(width=CLOCK_RADIUS*2.5, height=CLOCK_RADIUS*2.5)\n",
+    "canvas.translate(CLOCK_RADIUS * 1.2, CLOCK_RADIUS * 1.2)\n",
+    "display(canvas)\n",
+    "\n",
+    "def clear_drawing():\n",
+    "    canvas.clear_rect(-CLOCK_RADIUS * 1.2, -CLOCK_RADIUS * 1.2, canvas.width, canvas.height)\n",
+    "\n",
+    "def minutes_vec(minutes):\n",
+    "    a = minutes * np.pi/30\n",
+    "    return [np.sin(a), -np.cos(a)]\n",
+    "\n",
+    "def draw_dial():\n",
+    "    ht = 10\n",
+    "    mt = 6\n",
+    "    ho = 20\n",
+    "    mo = 10\n",
+    "\n",
+    "    canvas.text_align = 'center'\n",
+    "    canvas.text_baseline = 'middle'\n",
+    "\n",
+    "    canvas.line_width = 2\n",
+    "    canvas.stroke_circle(0, 0, CLOCK_RADIUS)\n",
+    "\n",
+    "    for m in range(60):\n",
+    "        a = m * np.pi/30\n",
+    "        x, y = np.sin(a), -np.cos(a)\n",
+    "\n",
+    "        canvas.line_width = 1\n",
+    "        if m % 5 == 0:\n",
+    "            canvas.stroke_line(x * (CLOCK_RADIUS - ht), y * (CLOCK_RADIUS - ht), x * CLOCK_RADIUS, y * CLOCK_RADIUS)\n",
+    "            canvas.font = '12px serif'\n",
+    "            canvas.stroke_text(str(m), x * (CLOCK_RADIUS + mo), y * (CLOCK_RADIUS + mo))\n",
+    "            canvas.font = '16px serif'\n",
+    "            canvas.stroke_text(str(m//5 if m > 0 else 12), x * (CLOCK_RADIUS - ho), y * (CLOCK_RADIUS - ho))\n",
+    "        else:\n",
+    "            canvas.stroke_line(x * (CLOCK_RADIUS - mt), y * (CLOCK_RADIUS - mt), x * CLOCK_RADIUS, y * CLOCK_RADIUS)\n",
+    "\n",
+    "def draw_hands(minutes):\n",
+    "    ms = 35\n",
+    "    hs = 50\n",
+    "\n",
+    "    hrs = minutes // 60\n",
+    "    mins = minutes % 60\n",
+    "\n",
+    "    mv = minutes_vec(mins)\n",
+    "    hv = minutes_vec(hrs * 5 + (mins / 12))\n",
+    "\n",
+    "    canvas.line_width = 5\n",
+    "    canvas.stroke_line(0, 0, mv[0] * (CLOCK_RADIUS - ms), mv[1] * (CLOCK_RADIUS - ms))\n",
+    "    canvas.stroke_line(0, 0, hv[0] * (CLOCK_RADIUS - hs), hv[1] * (CLOCK_RADIUS - hs))\n",
+    "\n",
+    "def draw_clock(hours, minutes):\n",
+    "    with hold_canvas(canvas):\n",
+    "        clear_drawing()\n",
+    "        draw_dial()\n",
+    "        draw_hands((hours % 12) * 60 + minutes)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "jupyter": {
+     "source_hidden": true
+    }
+   },
+   "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "230151983b1d45389070a9016d0c37fc",
+       "version_major": 2,
+       "version_minor": 0
+      },
+      "text/plain": [
+       "HBox(children=(IntText(value=21, continuous_update=True, layout=Layout(width='50px')), Label(value=':'), IntTe…"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "import datetime\n",
+    "import ipywidgets as widgets\n",
+    "\n",
+    "now = datetime.datetime.now()\n",
+    "\n",
+    "hour_text = widgets.IntText(value = now.hour, continuous_update=True, layout={'width': '50px'})\n",
+    "minute_text = widgets.IntText(value = now.minute, continuous_update=True, layout={'width': '50px'})\n",
+    "\n",
+    "def on_text_change(change):\n",
+    "    draw_clock(int(hour_text.value), int(minute_text.value))\n",
+    "\n",
+    "hour_text.observe(on_text_change, names='value')\n",
+    "minute_text.observe(on_text_change, names='value')\n",
+    "\n",
+    "display(widgets.HBox([hour_text, widgets.Label(value=':'), minute_text]))\n",
+    "\n",
+    "on_text_change(0)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "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": "3.8.6"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 4
+}