Add yt volume rendering scripts for focus session

yt-volume_rendering/2_camera_and_lens.ipynb

@@ -0,0 +1,135 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "import yt\n",
+    "import numpy as np\n",
+    "from yt.testing import fake_vr_orientation_test_ds\n",
+    "\n",
+    "ds = fake_vr_orientation_test_ds()"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": true
+   },
+   "outputs": [],
+   "source": [
+    "# now we do volume rendering\n",
+    "sc = yt.create_scene(ds, field='density')\n",
+    "# Change transfer function\n",
+    "tf = yt.ColorTransferFunction((np.log10(0.1), np.log10(1.)))\n",
+    "tf.sample_colormap(np.log10(0.9), 0.01, colormap=\"spectral\")\n",
+    "tf.sample_colormap(np.log10(0.8), 0.01, colormap=\"spectral\")\n",
+    "tf.sample_colormap(np.log10(0.6), 0.01, colormap=\"spectral\")\n",
+    "tf.sample_colormap(np.log10(0.2), 0.01, colormap=\"spectral\")\n",
+    "render_source = sc.get_source(0)\n",
+    "render_source.transfer_function = tf"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# plane-parallel lens\n",
+    "cam = sc.add_camera(ds, lens_type='plane-parallel')\n",
+    "cam.resolution = (500, 500) # equivalent with cam.set_resolution()\n",
+    "cam.width = ds.quan(4, 'code_length') # equivalent with cam.set_width()\n",
+    "cam.position = ds.arr([2.5, 0, 0], 'code_length') # equivalent with cam.set_position()\n",
+    "cam.switch_orientation(normal_vector=[-1, 0, 0],\n",
+    "                       north_vector=[0, 0, 1])\n",
+    "sc.render()\n",
+    "sc.show(sigma_clip=2.0)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# perspective lens\n",
+    "cam = sc.add_camera(ds, lens_type='perspective')\n",
+    "cam.resolution = (500, 500)\n",
+    "cam.width = ds.arr([2, 2, 1], 'code_length')\n",
+    "cam.position = ds.arr([2.5, 0, 0], 'code_length')\n",
+    "cam.switch_orientation(normal_vector=[-1, 0, 0],\n",
+    "                       north_vector=[0 ,0, 1])\n",
+    "sc.render()\n",
+    "sc.show(sigma_clip=6.0)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# spherical lens\n",
+    "cam = sc.add_camera(ds, lens_type='spherical')\n",
+    "cam.resolution = (1000, 500)\n",
+    "cam.position = ds.arr([0.5, 0, 0], 'code_length')\n",
+    "cam.switch_orientation(normal_vector=[-1 ,0 ,0],\n",
+    "                       north_vector=[0 ,0 ,1])\n",
+    "sc.render()\n",
+    "sc.show(sigma_clip=6.0)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": [
+    "# stereo-spherical lens (another similar lens is stereo-perspective)\n",
+    "cam = sc.add_camera(ds, lens_type='stereo-spherical')\n",
+    "cam.disparity = ds.domain_width[0] * 1.5e-3 # separation between two eyes\n",
+    "cam.resolution = (1000, 1000)\n",
+    "cam.position = ds.arr([0.5, 0, 0], 'code_length')\n",
+    "cam.switch_orientation(normal_vector=[-1 ,0, 0],\n",
+    "                       north_vector=[0, 0, 1])\n",
+    "sc.render()\n",
+    "sc.show(sigma_clip=6.0)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.11"
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+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}