Working with Deformers

Aspose.3D for .NET supports two deformation systems: skeletal deformation via SkinDeformer and Bone, which bind a skeleton to a mesh for character animation, and morph target deformation via MorphTargetDeformer, which blends between multiple mesh shapes.

Skeletal Deformation with SkinDeformer

A SkinDeformer attaches a set of Bone objects to a mesh. Each bone defines a weight for every vertex it influences. The mesh deforms when the bone transforms change.

using Aspose.ThreeD;
using Aspose.ThreeD.Deformers;
using Aspose.ThreeD.Entities;

var scene = new Scene();
var mesh = new Mesh("body");
Node meshNode = scene.RootNode.CreateChildNode("body", mesh);

// Create a SkinDeformer and attach it to the mesh
var skin = new SkinDeformer();
mesh.Deformers.Add(skin);

// Define a bone and assign per-vertex weights
var bone = new Bone("spine");
bone.BoneTransform = Matrix4.Identity;
bone.SetWeight(0, 1.0);
bone.SetWeight(1, 0.8);
skin.Bones.Add(bone);

Vertex indices passed to SetWeight must be valid indices in the mesh’s control-points array. Weights are typically normalized so they sum to 1.0 across all bones influencing a vertex.

Morph Target Deformation

MorphTargetDeformer blends the base mesh toward one or more target shapes. Each target is a separate mesh with the same topology but different vertex positions.

using Aspose.ThreeD;
using Aspose.ThreeD.Deformers;
using Aspose.ThreeD.Entities;

var scene = new Scene();
var baseMesh = new Mesh("face_neutral");
scene.RootNode.CreateChildNode("face", baseMesh);

// Target shape
var smileMesh = new Mesh("face_smile");

// Attach a MorphTargetDeformer
var morph = new MorphTargetDeformer();
baseMesh.Deformers.Add(morph);

// Add a morph channel targeting the smile mesh
var smileChannel = new MorphTargetChannel("smile");
smileChannel.Targets.Add(smileMesh);
morph.Channels.Add(smileChannel);

// At runtime, set the blend weight (0.0 = base, 1.0 = full target)
smileChannel.SetWeight(smileMesh, 0.75);

API Quick Reference

Member	Description
`new SkinDeformer()`	Create a skeletal deformer to attach to a mesh
`skin.Bones`	`IList<Bone>` of bones in this deformer
`new Bone(name)`	Create a named bone
`bone.SetWeight(vertexIndex, weight)`	Assign a blend weight to a vertex
`bone.BoneTransform`	Bind-pose offset matrix for this bone
`new MorphTargetDeformer()`	Create a morph target deformer
`morph.Channels`	`IList<MorphTargetChannel>` of blend channels
`new MorphTargetChannel(name)`	Create a named morph channel
`channel.Weight`	Blend weight: 0.0 = base, 1.0 = target
`channel.AddTarget(mesh, fullWeight)`	Register a target mesh for this channel
`mesh.Deformers`	Collection of deformers on a mesh

Working with Deformers