feat: Add rmesh structure docs

docs/pages/RMesh Structure.md

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+# RMesh Structure
+A Room Mesh (rmesh) file is the main room file in [SCP: Containment Breach](https://scpcbgame.com/). It is a basic mesh format designed to be house the room's mesh and baked entities.
+
+The rmesh comprises of 5 main chunks of data:
+- The header - Provides basic data about the mesh, such as whether or not it contains trigger boxes.
+- The drawn mesh - The visual part of the mesh.
+- The collision mesh - Not every room mesh has this, it's designed to add more collision for things like stairs or the HCZ tunnels.
+- Trigger boxes - A list of trigger boxes which are used by the game code to handle certain events.
+- Entities - Rooms have a specific list of entities that are baked in to the level, such as lights, models, sound emitters, screens and waypoints
+
+## Structure
+
+### Types
+#### Vertex
+A vertex is a struct that describes a mesh vertex.
+The structure of a vertex is:
+- X - float.
+- Y - float.
+- Z - float.
+- UV X - float.
+- UV Y - float.
+- Lightmap UV X - float.
+- Lightmap UV Y - float.
+- R - byte
+- G - byte
+- B - byte
+
+### Triangle
+A triangle is a struct of 3 uint32's that define what vertices are apart of the specified triangle.
+
+#### Surface
+A surface is a struct that describes a collection of triangles and vertices of the mesh. Surfaces are broken up
+by textures, meaning that all faces using the same texture are separated into 1 big surface.
+
+A surface structure is as followed:
+- Textures[2] - The first is usually the texture of the surface, and the second is usually the lightmap texture.
+- Vertex Count - The count of all the vertices. Type is uint32.
+- Vertices[Vertex Count] - An array of all the vertices for this surface.
+- Triangle Count - The count of all the triangles. Type is uint32.
+- Triangles[Triangle Count] - All the triangles for this surface.
+
+### Texture
+A texture is a basic struct containing a blend type and texture name.
+The texture name is only present when the blend type does not equal zero (0).
+
+NOTE: I'm not exactly sure what blend type is or what it's values are
+
+### Header
+The header is a size (uint32) prefixed string, usually it is either `RoomMesh` or `RoomMesh.HasTriggerBox`. (In SCP:CB NTF, they extended this to add `.HasNoColl`)
+
+```cpp
+std::uint32_t headerSize;
+std::string headerText;
+```
+
+### Drawn Mesh
+The drawn mesh is the visual mesh that is rendered with textures, but is also used for general collision geometry alongside the collision mesh.
+It comprises of an array of surfaces, each of which describes a collection of vertices and triangles broken up by texture.
+
+### Collision Mesh
+The collision mesh is similar to the drawn mesh, except it is not drawn and is used purely for collision. Not every room mesh has collision mesh
+surfaces, but notable rooms are 173's chamber for the stairs, and various HCZ rooms to stop the player from walking up the sides.
+
+An important difference between the drawn mesh and the collision mesh, is that the surface vertices are only the vertex positions. They do not contain any
+UV or color data.
+
+### Trigger boxes
+Trigger boxes are collision meshes with a name, they used by the same to handle starting certain events.
+A room mesh only has trigger boxes if the header contains `.HasTriggerBox.`
+
+Inside the rmesh, they are an array that starts with the size of the array, similar to how surfaces are defined.
+
+The structure for a trigger boxes is:
+- Collision Mesh - The actual mesh for the trigger box
+- Name - A length prefixed string containing the name that is used by the game code.
+
+### Entities
+Various entities are baked into the room mesh file. 
+They are defined in an array that starts with the entity count. The first value of an entity is always the entities class name (A length prefixed string),
+and the class name is used to dictate how to read the entity's binary data as they are not in any specific order.
+
+Below are the structure of various entities
+
+#### Screen
+A screen is a CB entity that displays a PNG on the player's view, usually hinting at lore for SCP:CB.
+
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Image path - A length prefixed string that contains the image path.
+
+#### Waypoint
+Waypoints are used the the in-game AI.
+
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+
+#### Light
+Despite lightmaps being baked, light entities are also baked into the room and spawned in game.
+If X, Y or Z is equal to zero, the light entity does not have range, color or intensity.
+
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Range - float. Range of the light. SCP:CB calculates this as `Range/2000.f` when creating the light in game.
+- Color - Length prefixed string containing the RGB values. (Yes it's a string, I'm not sure why..)
+- Intensity - float. Intensity value of the light. In-game, SCP:CB uses this as `Min(Intensity*0.8,1.0)`
+
+#### Spotlight
+Similar to lights, spotlights are also baked into the room mesh.
+If X, Y or Z is equal to zero, the spotlight entity does not have range, color, intensity, angles, inner or outer cone angles.
+
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Range - float. Range of the light. SCP:CB calculates this as `Range/2000.f` when creating the light in game.
+- Color - Length prefixed string containing the RGB values. (Yes it's a string, I'm not sure why..)
+- Intensity - float. Intensity value of the light. In-game, SCP:CB uses this as `Min(Intensity*0.8,1.0)`
+- Angle - Length prefixed string containing the pitch, yaw and roll. Only pitch and yaw are used in-game.
+- Inner cone angle - uint32. Defines the inner cone angle for the spotlight
+- Outer cone angle - uint32. Defines the outer cone angle for the spotlight
+
+#### Sound Emitter
+A sound emitter is an entity that plays a sound.
+NOTE: This isn't complete as I don't fully understand the code surrounding the sound emitter entities.
+
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Sound - uint32.
+- Range - float.
+
+#### Player start
+This entity is used to teleport the player when the room is loaded
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Angle - Length prefixed string containing the pitch, yaw and roll.
+
+#### Model
+A model entity that, when the room is loaded, spawns the mesh from the path and rotates, positions and scales it based on this entity's data.
+
+- Path - A length prefixed string that has a path to the model this entity uses.
+- Position X - float.
+- Position Y - float.
+- Position Z - float.
+- Pitch - float.
+- Yaw - float.
+- Roll - float.
+- Scale X - float.
+- Scale Y - float.
+- Scale Z - float.