Merge pull request #24 from vcync/feat/expressions

feat(expressions): adds docs for expressions

docs/.vuepress/config.js

@@ -25,11 +25,12 @@ module.exports = {
           collapsable: false,
           children: [
             '/v3/guide/',
+            '/v3/guide/media',
             '/v3/guide/modules',
             '/v3/guide/groups',
             '/v3/guide/audioReactivity',
             '/v3/guide/inputLinks',
-            '/v3/guide/media',
+            '/v3/guide/expressions',
             '/v3/guide/shortcuts',
             '/v3/guide/writingA2dModule',
           ],

docs/v3/guide/expressions.md

@@ -0,0 +1,40 @@
+---
+sidebarDepth: 2
+---
+
+# Expressions
+
+Found in the Input Configuration panel, Expressions allow shaping of a Module's property value.
+
+Input from an Audio Feature, MIDI CC or Tween are all routed through the Expression, allowing Expressions to boost, dampen, shape or entirely change the incoming value.
+
+Expressions are JavaScript syntax, anything that can be sucessfully validated in the JavaScript console.
+
+e.g.
+
+`value` is the incoming value.
+
+`value * 2` doubles the incoming value.
+
+`value / 2` halves the incoming value.
+
+`value > 0.5 ? 10 : 0` sets the value to 10 if the incoming value is over 0.5. If under, the value will be 0.
+
+Methods from [Math.js](https://mathjs.org/) are available in Expressions.
+
+e.g.
+
+`sqrt(value)`
+
+Other variables in the scope:
+
+|Variable|Type|Detail|
+|---|---|---|
+|`time`|Number|The time returned from `Date.now()`|
+
+
+::: tip
+Expressions get evaluated when the Module's property will update, through UI interaction or incoming value from an Input Configuration assignment.
+
+You cannot use Expressions to create oscillating values.
+:::