doc: Fix formatting of curve docs and reformulate array docs a bit.

Author: heinezen

doc/code/curves.md

@@ -17,6 +17,7 @@ Curves are an integral part of openage's event-based game simulation.
    2. [Container](#container)
       1. [Queue](#queue)
       2. [Unordered Map](#unordered-map)
+      3. [Array](#array)
 
 
 ## Motivation
@@ -256,33 +257,38 @@ allows access to all key-value pairs that were in the map at time `t`.
 
 
 #### Array
-Array curve containers are the equivalent to the `std::array` C++ containers. Unlike other curve containers, 
-each element of the underlying std::array is a `keyframecontainer` and when a value is added to the `Array curve`
-at a given index they are added to the respective `keyframecontainer` at that index as a keyframe. 
+
+Array curve containers store a fixed number of `n` elements where `n` is determined at compile-time.
+They are the curve equivalent to the `std::array` C++ containers. In comparison to `std::array` each
+element in the array curve container is tracked individually over time. Hence, each index is associated
+with its own `KeyframeContainer` whose keyframes can be updated independent from other indices.
+When a value is added to the `Array` curve at a given index, a new keyframe is added to the respective
+`KeyframeContainer` stored at that index.
 
 **Read**
 
 Read operations retrieve values for a specific point in time.
 
-| Method            | Description                                                              |
-| ----------------- | --------------------------------------- ---------------------------------|
-| `get(t, i)`       | Get value of index `i` at time <= `t`                                    |
-| `get(t)`          | Get array of keyframes at time <= `t`                                    |
-| `size()`          | Get size of the array                                                    |
-| `frame(t, i)`     | Get the time and value of the keyframe at index `i` with time <= `t`     |
-| `next_frame(t, i)`| Get the time and value of the first keyframe at index `i` with time > `t`|
+| Method             | Description                                                              |
+| ------------------ | ------------------------------------------------------------------------ |
+| `get(t, i)`        | Get value of element at index `i` at time <= `t`                         |
+| `get(t)`           | Get array of values at time <= `t`                                       |
+| `size()`           | Get the number of elements in the array                                  |
+| `frame(t, i)`      | Get the previous keyframe (time and value) at index `i` before or at `t` |
+| `next_frame(t, i)` | Get the next keyframe (time and value) at index `i` after `t`            |
 
 **Modify**
 
 Modify operations insert values for a specific point in time.
 
-| Method                    | Description                                                                               |
-| ------------------------- | ------------------------------------------------------------------------------------------|
-| `set_insert(t, i, value)` | Insert a new keyframe(`t`, `value`) at index `i`                                          |
-| `set_last(t, i, value)`   | Insert a new keyframe(`t`, `value`) at index `i`; delete all keyframes after time `t`     |
-| `set_replace(t, i, value)`| Insert a new keyframe(`t`, `value`) at index `i`; remove all other keyframes with time `t`|
+| Method                     | Description                                                                                |
+| -------------------------- | ------------------------------------------------------------------------------------------ |
+| `set_insert(t, i, value)`  | Insert a new keyframe(`t`, `value`) at index `i`                                           |
+| `set_last(t, i, value)`    | Insert a new keyframe(`t`, `value`) at index `i`; delete all keyframes after time `t`      |
+| `set_replace(t, i, value)` | Insert a new keyframe(`t`, `value`) at index `i`; remove all other keyframes with time `t` |
 
 **Copy**
+
 | Method           | Description                                                                                      |
-| ---------------- | ------------------------------------------------------------------------------------------------ | 
+| ---------------- | ------------------------------------------------------------------------------------------------ |
 | `sync(Curve, t)` | Replace all keyframes from self after time `t` with keyframes from source `Curve` after time `t` |