Added Model Liquid documentation

Author: FriskTheFallenHuman

docs/engine/fileformats/models/liquid.md

@@ -0,0 +1,63 @@
+---
+description: Liquid Model (.liquid)
+---
+
+import Tabs from '@theme/Tabs';
+import TabItem from '@theme/TabItem';
+import ReactPlayer from "react-player";
+
+# Liquid Model (.liquid)
+
+---
+
+## Overview
+
+---
+
+:::note
+
+Not to be confused by Liquid Physics, this article its for the rather unused Model Liquid
+
+:::
+
+Model Liquids are a rather special mode, they don't use a model mesh per say, but uses a `.liquid` file in the `liquid/` folder under
+the game folder.
+
+Liquid models are unique in the sense that they are create in runtime under the contents of the `.liquid` file:
+
+```C
+seed 1337420
+
+size_x 256
+size_y 256
+verts_x 16
+verts_y 16
+liquid_type 2
+density 0.97
+drop_height 4
+drop_radius 4
+drop_delay 1.0
+update_rate 30
+shader textures/base_floor/conc_panel02
+```
+
+Would create something like this:
+
+`testModel models/water2.liquid`
+
+<ReactPlayer controls src='https://www.youtube.com/watch?v=uxGFbWrluTA' />
+    
+## Breakdown
+
+A `.liquid` file consist of the next :
+
+- **size_x/size_y**: In Units, defines the size of the liquid plane.
+- **verts_x**: Must be at least two per axis.
+- **verts_y**: `scale_y = size_y / ( verts_y - 1 )`
+- **liquid_type**: defines the deform; must be 1, 2 or 3.
+- **density**: The actual "density" of a liquid, but rather a percentage of time of animation in which it deforms?
+- **drop_height**:
+- **drop_radius**:
+- **drop_delay**: In Seconds, controls how many second it takes for the liquid to rest.
+- **update_rate**: Dictates how fast the animation is. in hz [60 >= val > 0].
+- **shader**: The texture to be use for this liquid.