Skinned Mesh Renderer component

The Skinned Mesh Renderer component renders a deformable meshThe main graphics primitive of Unity. Meshes make up a large part of your 3D worlds. Unity supports triangulated or Quadrangulated polygon meshes. Nurbs, Nurms, Subdiv surfaces must be converted to polygons. More info
See in Glossary. Deformable meshes include skinned meshes (meshes that have bones and bind poses), meshes that have blend shapes, and meshes that run cloth simulation.

To render a regular mesh, use a Mesh RendererA mesh component that takes the geometry from the Mesh Filter and renders it at the position defined by the object’s Transform component. More info
See in Glossary and a Mesh FilterA mesh component that takes a mesh from your assets and passes it to the Mesh Renderer for rendering on the screen. More info
See in Glossary instead.

When you add a deformable mesh or a model with a deformable mesh to a sceneA Scene contains the environments and menus of your game. Think of each unique Scene file as a unique level. In each Scene, you place your environments, obstacles, and decorations, essentially designing and building your game in pieces. More info
See in Glossary, Unity adds a Skinned Mesh Renderer component to the resulting GameObjectThe fundamental object in Unity scenes, which can represent characters, props, scenery, cameras, waypoints, and more. A GameObject’s functionality is defined by the Components attached to it. More info
See in Glossary.

In C# code, the SkinnedMeshRenderer class represents a Skinned Mesh Renderer component. The SkinnedMeshRenderer class inherits much of its functionality from the Renderer class. As such, this component has a lot in common with other components that inherit from Renderer, such as Line RendererA component that takes an array of two or more points in 3D space and draws a straight line between each one. You can use a single Line Renderer component to draw anything from a simple straight line to a complex spiral. More info
See in Glossary, and Trail RendererA visual effect that lets you to make trails behind GameObjects in the Scene as they move. More info
See in Glossary.

Troubleshooting Skinned Mesh Renderer visibility

Unity uses the mesh’s bounds to determine whether to render it. If the entire bounding volumeA closed shape representing the edges and faces of a collider or trigger. More info
See in Glossary is outside the view of any active CameraA component which creates an image of a particular viewpoint in your scene. The output is either drawn to the screen or captured as a texture. More info
See in Glossary, Unity does not render the mesh.

In the case of a Skinned Mesh Renderer, its mesh bounds change as it deforms. Unity accounts for all animations present at import time when it calculates the maximum bounding volume, and uses this value to determine visibility; however, the following situations that occur after import might push vertices or bones outside of the maximum known bounds:

Additive animations
Changing the positions of bones from a script at runtime
Using vertex shadersA program that runs on the GPU. More info
See in Glossary that change vertex positions
Using ragdolls

If this happens, Unity might not correctly determine the visibility of the mesh, and might fail to show it when expected.

In these cases, you can try either of the following solutions to fix the problem:

Modify the bounds to match the maximum potential bounding volume of your mesh. Use this option if possible, because it is better for performance.
Enable Update When Offscreen, so that Unity continues to calculate the mesh bounds at all times, even when the mesh is not visible. Use this option if performance is not a major concern, or if you can’t predict the size of your bounding volume (for example, if you use ragdolls).

Skinned Mesh Renderer Inspector reference

The Skinned Mesh Renderer component as it appears in the Inspector window.

A: Properties
B: MaterialsAn asset that defines how a surface should be rendered. More info
See in Glossary

C: Lighting
D: Probes
E: Additional Settings

Properties

Property		Description
Bounds		Sets the bounding volume that Unity uses to determine when the mesh is offscreen. Unity pre-calculates the bounds when importing the mesh and animations in the Model file, and displays the bounds as a wireframe around the Model in the Scene view. If you set Update When Offscreen to True, Unity recalculates these bounds every frame and uses those calculated values to overwrite this property. This property corresponds to the Mesh.Bounds API.
BlendShapes		Stores the weight values that Unity uses with the blend shapes defined in the mesh.
Quality		Sets a runtime cap for the maximum number of bones that can affect a vertex. When Unity imports a mesh, Unity can skin every vertex with a number of bones from one to 32. A higher number of influential bones improves results during movement. However, this also increases the computational resources required, and therefore might affect performance. For performance reasons, it’s better to set the number of bones that affect a vertex on import, rather than using a runtime cap. To do this, use the Rig tab of the Model Import Settings window and adjust the Skin Weights setting. In addition to using this setting to set a runtime cap per-component, you can also set a global limit for your project under Edit > Project Settings > Quality > Other > Skin Weights. This property corresponds to the SkinnedMeshRenderer.quality API.
	Auto	Use the global limit set in Quality Settings > Skin Weights. Note: If you import a custom number of skin weights and you want to allow more than four bones of influence, you must choose this option and make sure you set Skin Weights to Unlimited.
	1 Bone	Use only one bone per vertex.
	2 Bones	Use up to two bones per vertex.
	4 Bones	Use up to four bones per vertex. To allow more than four bones to influence a single vertex, use the Auto setting.
Update When Offscreen		Enable this option to calculate the bounding volume at every frame, even when the mesh is not visible by any Camera. Disable this option to stop skinning when the GameObject is off-screen and resume it when the GameObject is visible again. This is disabled by default, for performance reasons. This property corresponds to the SkinnedMeshRenderer.updateWhenOffscreen API.
Mesh		Set the mesh that this Renderer uses. The mesh should either contain a valid bind pose and skin weights, use blend shapes, or run cloth simulation. If the mesh does not use any of these techniques, consider using a Mesh Renderer and a Mesh Filter. Corresponds to the SkinnedMeshRenderer.sharedMesh property.
Root bone		Set the transform that is the “root” of the skeleton. The bounds move along with this transform.
Rendering Layer Mask		This property determines which rendering layer Unity assigns this renderer to. You can use this property to specify an additional rendering-specific layer mask. This filters the renderers based on the mask the renderer has. This property corresponds to the Renderer.renderingLayerMask API. Unity only displays this property when you use a Scriptable Render Pipeline.
Renderer Priority		Sort renderers by priority. Lower values are rendered first and higher values are rendered last. This property corresponds to the Renderer.rendererPriority API. Unity only displays this property when you use the High Definition Render Pipeline.

Materials

Wireframe view of the meshes in Unity’s 2020.1 HDRP template example project

The Materials section lists all the materials that this component uses.

Property	Description
Size	The number of elements in the material list. If you decrease the number of elements, Unity deletes the elements at the end of the list. If you increase the number of elements, Unity adds new elements to the end of the list. Unity populates new elements with the same material that the element at the end of the list uses.
Element	The materials in the list. You can assign a material asset to each element. By default, Unity orders the list alphabetically based on the name of the materials. This list is reorderable, and Unity updates the number of the elements automatically as you change their order.

Note: If there are more materials than there are sub-meshes, Unity renders the last sub-mesh with each of the remaining materials, one on top of the next. If the materials are not fully opaque, you can layer different materials and create interesting visual effects. However, fully opaque materials overwrite previous layers, so any additional opaque materials that Unity applies to the last sub-mesh negatively affect performance and produce no benefit.

Lighting

The Lighting section contains properties that relate to lighting.

Property		Description
Cast Shadows		Specify if and how this Renderer casts shadows when a suitable Light shines on it. This property corresponds to the Renderer.shadowCastingMode API.
	On	This Renderer casts a shadow when a shadow-casting Light shines on it.
	Off	This Renderer does not cast shadows.
	Two-sided	This Renderer casts two-sided shadows. This means that single-sided objects like a plane or a quad can cast shadows, even if the light source is behind the mesh. For Baked Global Illumination or Enlighten Realtime Global Illumination to support two-sided shadows, the material must support Double Sided Global Illumination.
	Shadows Only	This Renderer casts shadows, but the Renderer itself isn’t visible.
Receive Shadows		Specify if Unity displays shadows cast onto this Renderer. This property only has an effect if you enable Baked Global Illumination or Enlighten Realtime Global Illumination for this scene. This property corresponds to the Renderer.receiveShadows API.
Contribute Global Illumination		Include this Renderer in global illumination calculations, which take place at bake time. This property only has an effect if you enable Baked Global Illumination or Enlighten Realtime Global Illumination for this scene. Enabling this property enables the Contribute GI flag in the GameObject’s Static Editor Flags. It corresponds to the StaticEditorFlags.ContributeGI API.
Receive Global Illumination		Whether Unity provides global illumination data to this Renderer from baked lightmaps, or from runtime Light Probes. This property is only editable if you enable Contribute Global Illumination. It only has an effect if you enable Baked Global Illumination or Enlighten Realtime Global Illumination for this scene. This property corresponds to the MeshRenderer.receiveGI API.
	Lightmaps	Unity provides global illumination data to this Renderer from lightmaps.
	Light Probes	Unity provides global illumination data to this Renderer from Light ProbesLight probes store information about how light passes through space in your scene. A collection of light probes arranged within a given space can improve lighting on moving objects and static LOD scenery within that space. More info See in Glossary in the scene.
Prioritize Illumination		Enable this property to always include this Renderer in Enlighten Realtime Global Illumination calculations. This ensures that the Renderer is affected by distant emissives, even those which are normally excluded from Global Illumination calculations for performance reasons. This property is visible only if Contribute GI is enabled in the GameObject’s Static Editor Flags, your project uses the Built-in Render Pipeline, and Enlighten Realtime Global Illumination is enabled in your scene.

Probes

The Probes section contains properties relating to Light Probe and Reflection ProbesA rendering component that captures a spherical view of its surroundings in all directions, rather like a camera. The captured image is then stored as a Cubemap that can be used by objects with reflective materials. More info
See in Glossary
.

Property		Description
Light Probes		Set how this Renderer receives light from the Light Probes system. This property corresponds to the Renderer.lightProbeUsage API.
	Off	The Renderer doesn’t use any interpolated Light Probes.
	Blend Probes	The Renderer uses one interpolated Light Probe. This is the default value.
	Use Proxy Volume	The Renderer uses a 3D grid of interpolated Light Probes.
	Custom Provided	The Renderer extracts Light Probe shader uniform values from the MaterialPropertyBlock.
Proxy Volume Override		Set a reference to another GameObject that has a Light Probe Proxy Volume component. This property is only visible when Light Probes is set to Use Proxy Volume.
Reflection Probes		Set how the Renderer receives reflections from the Reflection Probe system. This property corresponds to the Renderer.probeAnchor API.
	Off	Disables Reflection Probes. Unity uses a skybox for reflection.
	Blend Probes	Enables Reflection Probes. Blending occurs only between Reflection Probes. This is useful in indoor environments where the character may transition between areas with different lighting settings.
	Blend Probes and Skybox	Enables Reflection Probes. Blending occurs between Reflection Probes, or between Reflection Probes and the default reflection. This is useful for outdoor environments.
	Simple	Enables Reflection Probes, but no blending occurs between Reflection Probes when there are two overlapping volumes.
Anchor Override		Set the Transform that Unity uses to determine the interpolation position when using the Light Probe or Reflection Probe systems. By default, this is the centre of the bounding box of the Renderer’s geometry. This property corresponds to the Renderer.probeAnchor API.

Additional Settings

The Additional Settings section contains additional properties.

Property		Description
Skinned Motion Vectors		Enable this option to double-buffer the Mesh skinning data, so Unity can interpolate the skinned motion and place it into the motion vector Texture. This uses more GPU memory, but leads to more correct motion vectors.
Dynamic Occlusion		When Dynamic Occlusion is enabled, Unity’s occlusion cullingA feature that disables rendering of objects when they are not currently seen by the camera because they are obscured (occluded) by other objects. More info See in Glossary system culls this Renderer when it is blocked from a Camera’s view by a Static Occluder. Otherwise, the system does not cull this Renderer when it is blocked from a Camera’s view by a Static Occluder. Dynamic Occlusion is enabled by default. Disable it for effects such as drawing the outline of a character behind a wall.

Mesh Renderer component

Mesh Filter component