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--- manual:subwaysim:vehicle_development:blender_rigging [2025/12/16 09:54] – dcs
+++ manual:subwaysim:vehicle_development:blender_rigging [2026/01/07 07:13] (current) – [Creating the Armature] dcs
@@ Line 11: / Line 11: @@
 </WRAP>
+----
-=====Why Rigging is Important=====
+===== What is Rigging in the Context of Vehicles =====
-Rigging allows us to create **animated** vehicles in Unreal Engine.
+Rigging is the process of defining how individual parts of a vehicle can move relative to each other.
-By adding bones to the mesh and setting up a proper skeleton, we enable each part of the vehicle to move independently. This is crucial for:
-  * Animated parts like doors opening/closing
-  * Movable components like wheels and suspension
-  * Fine-grained control of physics-based interactions (e.g., suspension movement, door animations, etc.)
-Once the vehicle is rigged correctly in Blender, we can export it to Unreal Engine with all bones and weights intact, allowing the parts to be manipulated via **Blueprints** and **Control Rigs**.
+Unlike characters, vehicles are mostly **mechanical objects**.
+This means we usually do not deform meshes smoothly, but instead rotate or move rigid parts such as:
+  * Doors
+  * Door handles
+  * Windshield wipers
+  * Pantographs
+  * Bogies and suspension parts
+To achieve this reliably and cleanly, SubwaySim 2 vehicles are rigged using an **Armature**.
+----
+===== Rigging with Armature (Recommended Workflow) =====
+An **Armature** is a skeleton made up of bones.
+Each bone controls one or more parts of the vehicle and defines how they move.
+All animated parts of the vehicle are rigged under a **single Armature**, similar to how a character is rigged.
+----
+===== Preparing the Mesh =====
+Before creating the Armature, make sure that:
+  * All movable parts are separate meshes
+  * Pivots are placed correctly at real-world rotation points
+  * Object rotations and scales are applied
+  * Mesh orientation is correct (X Forward, Z Up)
+A clean mesh setup is essential.
+Incorrect pivots or unapplied transforms will cause issues later in Unreal Engine.
+----
+===== Creating the Armature =====
+Create a new Armature object and begin adding bones.
+Important characteristics of Blender bones:
+  * Blender is **bone-based**, not joint-based
+  * The **start of a bone** defines the rotation point
+  * The **end of a bone** defines the orientation
+Bones should be placed so that:
+  * The bone origin sits exactly on the pivot of the mesh it controls
+  * The bone points in the same direction as the mesh’s local orientation
+There is **no need to create a separate root bone**.
+The Armature object itself already acts as a root.
+{{:manual:subwaysim:blender_rigging:rig1.png?direct&800|}}
+----
+===== Bone Orientation =====
+Bone orientation is critical for correct behavior in Unreal Engine.
+Important rules:
+  * Bone local forward axis is **Y Forward**
+  * Bone orientation must match the mesh orientation
+  * Bone roll must be adjusted correctly
+Bone roll can be adjusted in **Edit Mode** using the *Roll* settings to align the X and Z axes.
+Incorrect bone orientation will lead to:
+  * Inverted rotations
+  * Incorrect animation behavior
+  * Problems in Animation Blueprints and Control Rigs
+----
+===== Skinning the Mesh to the Armature =====
+Once the bones are placed correctly, the mesh must be skinned to the Armature.
+For mechanical vehicles, we generally avoid smooth deformation.
+Instead, each mesh or mesh part should be fully controlled by one bone.
+There are multiple ways to do this, but when using an Armature, the most common approaches are:
+  * Parenting meshes directly to bones
+  * Using Vertex Groups with matching bone names
+{{:manual:subwaysim:blender_rigging:rig2.png?direct&800|}}
+The exact method depends on the complexity of the vehicle and will be explained in later sections.
+----
+===== Animating with an Armature =====
+One major advantage of using an Armature is animation control.
+Because all moving parts are part of the same Armature:
+  * All animations can be stored in a single NLA strip
+  * Complex interactions (e.g. door + handle) can be animated together
+  * Runtime control in Unreal Engine becomes significantly easier
+This is essential for SubwaySim 2 vehicles, where multiple systems often move simultaneously.
+----
+===== Export .Fbx =====
+When exporting a rigged vehicle from Blender to Unreal Engine, it is important to note that **there is no single universal export setup**.
+Depending on what is being exported, **different FBX export settings are required**.
+For SubwaySim 2, we distinguish between:
+  * Export settings for **Exterior and Interior meshes**
+  * Export settings for **Cab meshes**
+  * Special export settings for **Animations**
+Each of these cases has its own specific requirements and options.
+----
+==== General Export Guidelines ====
+Before exporting any FBX file, always ensure the following:
+  * Only required bones are present in the Armature
+  * Bone orientation has been verified one last time
+  * Transforms (rotation and scale) are applied correctly
+For all vehicle-related exports, the option:
+**Add Leaf Bones**must be **disabled**.
+Blender automatically adds end bones when this option is enabled.
+Unreal Engine interprets these as additional bones, which leads to unwanted and confusing “ghost bones” in the skeleton.
+Disabling this option ensures a clean skeleton structure inside Unreal Engine.
+----
+==== Export Presets and Screenshots ====
+The exact FBX export settings differ depending on the asset type and are documented in detail using screenshots.
+Please refer to the corresponding screenshots in the following sections to ensure that:
+  * The correct export preset is used
+  * All required options are enabled
+  * No unnecessary data is exported
+Using the correct export settings is essential to avoid issues later when importing meshes, animations, or setting up Control Rigs and Animation Blueprints.
+**Exterior/Interior Export Settings:**
+{{:manual:subwaysim:blender_rigging:blender1.png?direct&100|}}
+**Cab Export Settings:**
+{{:manual:subwaysim:blender_rigging:blender2.png?direct&100|}}
+**Animation Export Settings:**
+{{:manual:subwaysim:blender_rigging:blender3.png?direct&100|}}
+----
+===== Summary =====
+Rigging vehicles using an Armature provides:
+  * Clean structure
+  * Reliable animation control
+  * Good performance
+  * Compatibility with Unreal Engine systems
+For SubwaySim 2 vehicles, this workflow is the recommended foundation for all further steps, including animation setup and vehicle Blueprint creation.
+{{page>manual:footer}}
-======The Rigging Process in Blender======