glTF Models

Cocos Creator supports glTF 2.0 and earlier file formats.

URI Parsing

Creator supports URIs in the following form specified in glTF:

• Data URI

• Relative URI path

• File URL

• File path

Conversion Relationships

When importing a glTF model into Creator, the assets in glTF will be converted to assets in Creator according to the following relationships:

glTF Scene

After import, the glTF scene will be converted to a prefab asset in Creator, and the nodes recursively contained in the glTF scene will be converted to nodes in the prefab one by one according to the same hierarchical relationship.

Scene Root Node

The prefab will use a node without any spatial transformation information as the root node, and all root nodes of the glTF scene will be the children of this node.

Node Conversion

The properties in the glTF node will be converted to properties in the prefab node according to the texture relationships in the following table:

MeshRenderer

If the glTF node references a mesh, then the corresponding prefab node will also have a MeshRenderer component added to it after import. If the glTF node also references a skin, then the corresponding prefab node will also have a SkinnedMeshRenderer added to it.

The mesh, skeletons, and materials in the SkinnedMeshRenderer component correspond to the transformed glTF mesh, skin, and material assets.

If the glTF node specifies an initial weight, the converted (skinned) MeshRenderer will also carry this weight.

glTF Mesh

After import, the glTF mesh will be converted to a mesh asset in Cocos Creator.

All primitives in the glTF mesh will be converted to sub-meshes in the Creator one by one.

If weight is specified for the glTF mesh, the corresponding weights will be stored in the converted Creator mesh.

glTF Primitive

The index arrays of the glTF primitives will correspond to the index arrays of the converted Cocos Creator sub-meshes.

The glTF primitive schema will be converted to the Cocos Creator primitive schema according to the texture in the following table.

glTF vertex attributes will be converted to Cocos Creator vertex attributes, and the attribute names will be converted as shown in the following table:

Note: if there are other JOINTS, WEIGHTS vertex attributes in the glTF primitive, such as JOINTS_1, WEIGHTS_1, it means that the vertices of this glTF mesh may be affected by more than 4 skeletons.

For each vertex, all the weight information determined by JOINTS_{}, WEIGHTS_{} will be sorted by weight value and the four skeletons with the highest influence weight will be taken as gfx.AttributeName.ATTR_JOINTS and gfx.AttributeName.ATTR_WEIGHTS.

glTF deformation targets will be converted to Cocos Creator sub-mesh deformation data.

glTF Skins

After import, glTF skins will be converted to skeletal assets in Cocos Creator.

glTF Material

After import, glTF materials will be converted to material assets in Cocos Creator.

glTF Texture

After import, glTF texture will be converted to a texture asset in Cocos Creator.

The glTF image referenced in the glTF texture will be converted to a reference to the corresponding converted Cocos Creator image.

glTF texture properties will be converted to Cocos Creator texture properties according to the texture in the following table:

The glTF texture magnification filter will be converted to the Cocos Creator texture magnification filter according to the texture in the following table:

The glTF Texture Minification Filter will be converted to Cocos Creator Texture Minification Filter and Cocos Creator Texture Mip Map Filter according to the texture relationships in the following table:

glTF Texture Wrap mode will be converted to Cocos Creator Texture Wrap mode according to the texture in the following table:

glTF Image

After import, the glTF image will be converted to an image asset in Cocos Creator.

When the URI of the glTF image is a Data URI, the image data will be fetched from the Data URI. Otherwise, the image data will be resolved from the Data URI according to the Cocos Creator Image Location Resolution Algorithm, where url is the URI of the glTF image and startDir is the directory where the glTF file is located.

glTF Animation

After import, glTF animations will be converted to Cocos Creator animation assets.