First stab at physics example for tutorial.

Former-commit-id: 904d556aa1b0beaaeb8adae67dedd63c57abb6da

docs/gallery.md

@@ -211,3 +211,18 @@ This file is auto-generated by docs/render_all.sh. DO NOT EDIT.
 
 <br/><hr><br/>
 
+## tut_glue_physics
+
+<details>
+  <summary>View tut_glue_physics.hs</summary>
+  <pre><code class="haskell">
+  {!examples/tut_glue_physics.hs!}
+  </code></pre>
+</details>
+<br/>
+<video width="640" height="360" autoplay loop>
+  <source src="https://github.com/Lemmih/reanimate/raw/master/docs/rendered/tut_glue_physics.mp4">
+</video>
+
+<br/><hr><br/>
+

docs/gen_gallery.sh

@@ -3,7 +3,8 @@
 ROOT=`stack path --project-root`
 EXAMPLES='boundingbox colormaps goo latex_basic latex_color latex_draw
           latex_wheel raster sphere blender_default_cube
-          tut_glue_svg tut_glue_animate tut_glue_keyframe tut_glue_fourier'
+          tut_glue_svg tut_glue_animate tut_glue_keyframe tut_glue_fourier
+          tut_glue_physics'
 
 WIDTH=640
 HEIGHT=$((WIDTH*9/16))

docs/glue_tut.md

@@ -86,6 +86,19 @@ The following examples shows how something as seemingly complicated as fourier s
 TODO: Write about how lots of libraries are available for Haskell. Use chiphunk
       as an example. Show SVG primitives with 2D physics.
 
+<details>
+  <summary>Toggle source code.</summary>
+  <pre><code class="haskell">
+  {!examples/tut_glue_physics.hs!}
+  </code></pre>
+</details>
+<br/>
+<video width="640" height="360" autoplay loop>
+  <source src="../rendered/tut_glue_physics.mp4">
+  <source src="https://github.com/Lemmih/reanimate/raw/master/docs/rendered/tut_glue_physics.mp4">
+</video>
+
+
 ## Pillar II: LaTeX
 
 TODO: Show that LaTeX is a provider of SVG graphics. It has the type