Ce site est optimisé pour être consulté depuis un navigateur moderne dans lequel JavaScript est activé.

spine-c - spBone and spBoneData fields

Irbis

I debug an application which uses spine-c. spBoneData contains the following fields:

float x, y, rotation, scaleX, scaleY, shearX, shearY;

The same fields are present in spBone struct. During animation the mentioned spBoneData fields remain the same.
Moreover spBone contains the following fields:

float ax, ay, arotation, ascaleX, ascaleY, ashearX, ashearY;

During animation those fields contains the same values as fields without a-prefix from spBone struct.

What is the difference between those fields, for example spBoneData::x vs spBone::x vs spBone::ax ?

Nate

The a fields are the "applied" values, in the docs here: Bone aRotation

Also see Bone isAppliedValid and Bone updateAppliedTransform. They are used by IkConstraint and TransformConstraint but are seldom needed by user code.

Irbis

spBone struct contains a pointer to spBoneData struct but both structs contains the same fields:

float x, y, rotation, scaleX, scaleY, shearX, shearY;

What is difference between them ? It's doesn't look like a clear design.

spBone struct contains a pointer to spBoneData struct but both structs contains the same fields:

float x, y, rotation, scaleX, scaleY, shearX, shearY;

What is difference between them ? It's doesn't look like a clear design.

Nate

*Data classes are shared across skeleton instances while classes without the Data suffix are per instance. BoneData is storing the setup pose transform while Bone is storing the skeleton instance's transform. Please see:
Runtime Architecture - Spine Runtimes Guide: Class diagram