Support for ?presentation query param (#36)

* Support for ?presentation query param

* Use the existing pattern for param parsing

* Add a note in the readme

README.md

@@ -12,6 +12,10 @@ Example: https://dreampuf.github.io/GraphvizOnline/?url=https://gist.githubuserc
 
 Using https://gist.github.com/ allows you to share and version your graph definitions.
 
+## Presentation mode
+
+If you would like to display just the graph and not the graph input, you can add a `?presentation` query param. This can be helpful when generating links with the graph already prefilled.
+
 # How to implement this
 
 - [viz.js](https://github.com/mdaines/viz.js) This repo has compile graphviz(C) to javascript via [emscripten](https://github.com/kripken/emscripten).

index.html

@@ -10,6 +10,18 @@
             margin: 0 0;
         }
 
+        body.presentation #editor {
+            display: none;
+        }
+
+        body.presentation #options {
+            left: 0;
+        }
+
+        body.presentation #review {
+            left: 0;
+        }
+
         #editor {
             margin: 0;
             position: absolute;
@@ -497,6 +509,10 @@
       }
     }
 
+    if (params.has("presentation")) {
+      document.body.classList.add("presentation");
+    }
+
     if (params.has('raw')) {
       editor.getSession().setValue(params.get('raw'));
       renderGraph();