improve doc, adaptation of #250

Co-authored-by: JadAbouHawili <jad-abou-hawili@hotmail.com>

doc/create_game.md

@@ -194,7 +194,7 @@ You can but a `Statement` inside namespaces like you would with `theorem`.
 
 #### Doc String / Exercise statement
 
-Add a docstring that contains the exercise statement in natural language. If you do this, it will appear at the top of the exercise. It supports Latex.
+Add a docstring that contains the exercise statement in natural language. If you do this, it will appear at the top of the exercise. See [LaTeX in Games](latex.md) for more details on formatting.
 
 ```lean
 /-- The exercise statement in natural language using latex: $\iff$. -/
@@ -265,13 +265,21 @@ CoverImage "images/cover.png"
 * `Prerequisites` a list of other games you should play before this one, e.g. `Prerequisites "NNG" "STG"`. The game names are free-text.
 * `CoverImage`: You can create a folder `images/` and put images there for the game to use. The maximal ratio is ca. 500x200 (W x H) but it might be cropped horizontally on narrow screens.
 
-## Further Notes
+## 10. Advanced Topics
 
-Here are some random further things you should consider designing a new game:
+### Escaping
 
-* Inside strings, you need to escape backslashes, but not inside doc-strings, therefore you
+Inside strings, you need to escape backslashes, but not inside doc-strings, therefore you
   would write `Introduction "some latex here: $\\iff$."` but
   `/-- some latex here: $\iff$. -/ Statement ...`
-* A world with more than 16 levels will be displayed with the levels spiraling outwards,
-  it might be desirable to stay below that bound. Above 22 levels the spiral starts getting out
-  of control.
+
+### LaTeX support
+
+LaTeX is rendered using the [KaTeX library](https://katex.org/),
+see [Using LaTeX in the Game](latex.md) for details.
+
+### Number Of Levels Limit
+
+A world with more than 16 levels will be displayed with the levels spiraling outwards,
+it might be desirable to stay below that bound. Above 22 levels the spiral starts getting out
+of control.

doc/hints.md

@@ -49,6 +49,9 @@ Statement .... := by
 Put variables in the hint text inside brackets like this: `{h}`! This way the server can replace
 the variable's name with the one the user actually used.
 
+*Note*: This means you need to escape any other uses of **opening** curly brackets (i.e. `\{`). See also [LaTeX in Games](latex.md) for
+examples of this.
+
 For example, if the sample proof contains
 
 ```
@@ -84,39 +87,19 @@ create new assumptions.
 
 ## 6. Formatting
 
-You can add use markdown to format your hints, for example you can use KaTex: `$\\iff$`
-
-**Escaping**: Generally, if you add text inside quotes `" "` (e.g. in `Hint`) you need to escape
-backslashes, but if you provide text inside a doc comment
-`/-- -/` (e.g. in the `Statement` description) you do not!
-Further, inside `Hint` you need to escape all opening curly brackets as `\{` since `{h}` is syntax for inserting a variable name `h`.
+You can use Markdown to format your hints and you can
+use LaTeX. See [LaTeX in Games](latex.md) for more details.
 
-TODO: Write a doc about latex/markdown options available.
+### Images
 
-### Commutative diagrams
+Hints and introductions/conclusions can also contain images.
 
-Here is an example of how to write a commutative diagram in KaTeX:
-
-$$
-\begin{CD}
-      A  @>{f}>> B @<{g}<< C    \\
-  @V{h}VV    @V{i}VV   @V{j}VV \\
-      D  @<{k}<< E @>{l}>> F    \\
-  @A{m}AA    @A{n}AA   @V{p}VV \\
-      G  @<{q}<< H @>{r}>> I
-\end{CD}
-$$
+For remote images, simply add:
 
 ```
-$$
-\\begin{CD}
-      A  @>{f}>> B @<{g}<< C    \\\\
-  @V{h}VV    @V{i}VV   @V{j}VV \\\\
-      D  @<{k}<< E @>{l}>> F    \\\\
-  @A{m}AA    @A{n}AA   @V{p}VV \\\\
-      G  @<{q}<< H @>{r}>> I
-\\end{CD}
-$$
+<img src=\"https://url.com/to/image\"/>
 ```
 
-See https://www.jmilne.org/not/Mamscd.pdf
+Local images can currently only be included with a hack:
+
+Images in the game's `images/` folder will be accessible at `data/g/[user]/[repo]/[image].[png|jpg|…]` and thus can be included as if they were external images.

doc/latex.md

@@ -0,0 +1,78 @@
+There are multiple ways how to format the text content of your game. Notably Markdown with KaTeX.
+
+# Escaping
+Generally, if you add text inside quotes `" "` (e.g. in `Hint`) you need to escape
+backslashes, but if you provide text inside a doc comment
+`/-- -/` (e.g. in the `Statement` description) you do not!
+
+This means for example you'd write `/-- $\iff$ -/` but `"$\\iff$"`.
+
+Furthermore, inside `Hint` you need to escape all opening curly brackets as `\{` since `{h}` is syntax for inserting a variable name `h`.
+
+# KaTeX
+
+LaTeX syntax is provided trough the [KaTeX library](https://katex.org). KateX supports most but not all of latex and its packages.
+See [supported](https://katex.org/docs/supported.html).
+
+## Examples
+
+### Commutative diagrams
+
+Here is an example of how to write a commutative diagram in KaTeX:
+
+$$
+\begin{CD}
+      A  @>{f}>> B @<{g}<< C    \\
+  @V{h}VV    @V{i}VV   @V{j}VV \\
+      D  @<{k}<< E @>{l}>> F    \\
+  @A{m}AA    @A{n}AA   @V{p}VV \\
+      G  @<{q}<< H @>{r}>> I
+\end{CD}
+$$
+
+```
+$$
+\begin{CD}
+      A  @>{f}>> B @<{g}<< C    \\
+  @V{h}VV    @V{i}VV   @V{j}VV \\
+      D  @<{k}<< E @>{l}>> F    \\
+  @A{m}AA    @A{n}AA   @V{p}VV \\
+      G  @<{q}<< H @>{r}>> I
+\end{CD}
+$$
+```
+
+Again, note that inside a string like `Hint`/`Introduction`/`Conclusion`/etc. you need to escape `\` and potentially `{`.
+
+E.g. `\begin` as `\\begin`, `\\` as `\\\\` and inside a
+`Hint`, `@>{f}>>` as `@>\{f}>>`.
+
+See https://www.jmilne.org/not/Mamscd.pdf
+
+### Truth Tables
+
+KaTeX does not support the tabular environment. You can use the array environment instead.
+
+$$
+\begin{array}{|c|c|}
+  \hline
+  P & ¬P \\
+  \hline
+  T & F  \\
+  F & T  \\
+  \hline
+\end{array}
+$$
+
+```
+$$
+\begin{array}{|c|c|}
+  \hline
+  P & ¬P \\
+  \hline
+  T & F  \\
+  F & T  \\
+  \hline
+\end{array}
+$$
+```