R6 Class for glTF file objects

The glTF file spec is described here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html. This object encapsulates most of the data from those files.

Super class

rgl::Buffer -> gltf

Public fields

scene: The default scene number

Methods

Inherited methods

Method `new()`

Usage

Gltf$new(json = NULL, defaultbin = NULL)

Arguments

json: List read from glTF file.
defaultbin: Optional external binary file.

Method `addAccessor()`

Write values to accessor, including min and max.

The glTF standard requires min and max values in accessors, whereas other uses of buffers may not. This function stores in the usual way using the Buffer$addAccessor() method, and then adds min and max values.

The standard also doesn't support signed 4 byte integers or double precision values, so we test for those here.

Usage

Gltf$addAccessor(values, target = NULL, types = "anyGLTF", normalized = FALSE)

Arguments

values: Values to write.
target: Optional target use for values.
types: Allowed types (from names of rgl::gltfTypes), or c("any", "anyGLTF")).
normalized: Are these normalized integer values?

Returns

New accessor number.

Method `getScene()`

Get scene object.

Usage

Gltf$getScene(sc)

Arguments

sc: Scene number.

Returns

Scene object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-scene.

Method `setScene()`

Update scene record.

Usage

Gltf$setScene(sc, scene)

Arguments

sc: Which scene to update.
scene: New scene record.

Method `addScene()`

Add a scene object.

Usage

Gltf$addScene()

Returns

Scene number.

Method `addToScene()`

Add node to scene.

Usage

Gltf$addToScene(scene, node)

Arguments

scene: Scene number to modify.
node: Node number(s) to add.

Method `defaultScene()`

Get default scene, creating it if necessary.

Usage

Gltf$defaultScene()

Returns

Scene number.

Method `getNode()`

Get node object.

Usage

Gltf$getNode(n)

Arguments

n: Node number.

Returns

Node object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-node.

Method `setNode()`

Set node object.

Usage

Gltf$setNode(n, node)

Arguments

n: Node number.
node: New node object.

Method `addNode()`

Add a node object.

Usage

Gltf$addNode(mesh = NULL, matrix = NULL, extras = NULL)

Arguments

mesh: A mesh number.
matrix: A matrix transformation for the node.
extras: A list of extras, typically rgl objects.

Returns

Node number.

Method `addChild()`

Add node as child of another.

Usage

Gltf$addChild(parent, node)

Arguments

parent: Node number to modify.
node: Node number(s) to add as children.

Method `setParents()`

Set parent member for all nodes

Usage

Gltf$setParents()

Method `getSkin()`

Get skin object.

Usage

Gltf$getSkin(skin)

Arguments

skin: Skin number.

Returns

Skin object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-skin.

Method `setSkin()`

Set skin object.

Usage

Gltf$setSkin(n, skin)

Arguments

n: Skin number.
skin: New skin object.

Method `getJoint()`

Get joint node.

Usage

Gltf$getJoint(skin, num)

Arguments

skin: Skin number.
num: Joint number.

Returns

Node object

Method `getInverseBindMatrices()`

Get "inverse bind matrices".

These matrices undo the existing transformation before applying the skin transformations.

Usage

Gltf$getInverseBindMatrices(skin)

Arguments

skin: Skin number.

Returns

A 4x4xn array of matrices, one per joint.

Method `getForwardBindMatrices()`

Get "forward bind matrices".

These matrices applying the skin transformations.

Usage

Gltf$getForwardBindMatrices(skin)

Arguments

skin: Skin number.

Returns

A 4x4xn array of matrices, one per joint.

Method `getCamera()`

Get camera object.

Usage

Gltf$getCamera(cam)

Arguments

cam: Camera number.

Returns

Camera object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-camera.

Method `getExtras()`

Get top-level extras list.

Usage

Gltf$getExtras()

Returns

Extras list, including rgl objects.

Method `setExtras()`

Set extras list.

Usage

Gltf$setExtras(extras)

Arguments

extras: New extras list.

Method `getMesh()`

Get mesh object.

Usage

Gltf$getMesh(m)

Arguments

m: Mesh number.

Returns

Mesh object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-mesh.

Method `setMesh()`

Set mesh object.

Usage

Gltf$setMesh(m, mesh)

Arguments

m: Mesh number.
mesh: New mesh object

Method `addMesh()`

Add a mesh object.

Usage

Gltf$addMesh(primitives)

Arguments

primitives: A list of primitive objects.

Returns

Mesh number.

Method `getMaterial()`

Get material object.

Usage

Gltf$getMaterial(m)

Arguments

m: Material number.

Returns

Material object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-material.

Method `getTexture()`

Get texture object.

Usage

Gltf$getTexture(tex)

Arguments

tex: Texture number.

Returns

Texture object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-texture.

Method `getImage()`

Get image object.

Usage

Gltf$getImage(im)

Arguments

im: Image number.

Returns

Image object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-image.

Method `addMaterial()`

Construct and possibly add material.

This will return an existing material if possible.

Usage

Gltf$addMaterial(mat, defaultMaterial = list())

Arguments

mat: An rgl material record.
defaultMaterial: Default material properties.

Returns

Material number.

Method `addTexture()`

Add a texture.

Usage

Gltf$addTexture(mat)

Arguments

mat: An rgl material record.

Returns

Texture number.

Method `addImage()`

Add an image for a texture.

Usage

Gltf$addImage(mat)

Arguments

mat: An rgl material record.

Returns

Image number.

Method `addSampler()`

Add a sampler.

Usage

Gltf$addSampler(mat)

Arguments

mat: An rgl material record.

Returns

Sampler number.

Method `getMaterialNumber()`

Add or return a material.

Usage

Gltf$getMaterialNumber(material)

Arguments

material: A glTF material record.

Returns

Material number.

Method `writeVectors()`

Write data.

Usage

Gltf$writeVectors(
  coords,
  target = targetArray,
  types = "anyGLTF",
  normalized = FALSE
)

Arguments

coords: Data to write, or NULL.
target: Optional target use for data.
types: A character vector of allowed types, or "any" or "anyGLTF"
normalized: Are these integer values representing floats?

Returns

Accessor number, or NULL.

Method `makePrimitive()`

Create a primitive record.

Usage

Gltf$makePrimitive(inds, mode = NULL, attributes = NULL, matnum = NULL)

Arguments

inds: Indices of vertices.
mode: Mode of primitive.
attributes: Primitive attributes.
matnum: Material number.

Returns

Primitive record, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-primitive.

Method `getAsset()`

Get asset list.

Usage

Gltf$getAsset()

Returns

Asset object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-asset.

Method `setAsset()`

Set asset list.

Usage

Gltf$setAsset(version, generator)

Arguments

version: Version number of glTF format.
generator: Identifier of code generating it.

Method `getTransform()`

Get local transform.

Usage

Gltf$getTransform(n)

Arguments

n: Node number.

Returns

4x4 matrix of local transform.

Method `getRglMaterial()`

Reconstruct rgl material.

Usage

Gltf$getRglMaterial(n)

Arguments

n: Material number.

Returns

rgl material record.

Method `getAnimation()`

Get animation.

Usage

Gltf$getAnimation(ani)

Arguments

ani: Animation number

Returns

Animation object, documented here: https://www.khronos.org/registry/glTF/specs/2.0/glTF-2.0.html#reference-animation.

Method `setAnimation()`

Set animation.

Usage

Gltf$setAnimation(ani, animation)

Arguments

ani: Animation number
animation: New animation object

Method `timerange()`

Find time range of an animation

Usage

Gltf$timerange(ani)

Arguments

ani: Animation number

Returns

Min and max times from the samplers in the animation.

Method `initAnimation()`

Initialize animation.

This builds all of the interpolation functions in the samplers.

Usage

Gltf$initAnimation(ani)

Arguments

ani: Animation number

Returns

Modified animation object

Method `settime()`

Set time for an animation.

This evaluates all the interpolators and modifies self to reflect the specified time point.

Usage

Gltf$settime(time, ani = 0)

Arguments

time: Time to set.
ani: Animation number.

Returns

Vector of node numbers that were changed.

Method `print()`

Print gltf objects with various levels of detail.

Usage

Gltf$print(verbose = FALSE, names = FALSE, showExtras = TRUE, ...)

Arguments

verbose: Logical indicator of verbose printing, or character vector of components to print verbosely.
names: Print names for components.
showExtras: Logical: show extra fields?
...: Passed ... .

Examples

samples <- "https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Models/master/2.0"
gltf <- readGLB(paste0(samples, "/2CylinderEngine/glTF-Binary/2CylinderEngine.glb?raw=true"))
gltf$print(names = "meshes")

Method `listCount()`

Get number of items in private list.

Usage

Gltf$listCount(list)

Arguments

list: Name of list to get.

Method `clone()`

The objects of this class are cloneable with this method.

Usage

Gltf$clone(deep = FALSE)

Arguments

deep: Whether to make a deep clone.

Examples


## ------------------------------------------------
## Method `Gltf$print`
## ------------------------------------------------

samples <- "https://raw.githubusercontent.com/KhronosGroup/glTF-Sample-Models/master/2.0"
gltf <- readGLB(paste0(samples, "/2CylinderEngine/glTF-Binary/2CylinderEngine.glb?raw=true"))
gltf$print(names = "meshes")
#> asset fields:
#>   GLtf version 2.0 file.
#>   Generated by COLLADA2GLTF.
#> Scenes ( 1 )
#> Nodes ( 82 )
#> Buffers ( 1 )
#> Bufferviews ( 2 )
#> Meshes ( 29 )
#>   0: Piston_123-844_0_Parts_1
#>   1: body_24
#>   2: body_23
#>   3: body_22
#>   4: body_21
#>   5: body_20
#>   6: Spring_Link__0_Parts_1
#>   7: body_19
#>   8: body_18
#>   9: body_17
#>   10: body_16
#>   11: body_15
#>   12: body_14
#>   13: body_13
#>   14: body_12
#>   15: body_11
#>   16: body_10
#>   17: body_9
#>   18: body_8
#>   19: body_7
#>   20: body_6
#>   21: body_5
#>   22: body_4
#>   23: body
#>   24: body_3
#>   25: body_2
#>   26: body_1
#>   27: rod_123-699_0_Parts_1
#>   28: Lifter_123-923_0_Parts_1
#> Cameras ( 1 )
#> Accessors ( 102 )
#> Materials ( 34 )

Super class

Public fields

Methods

Public methods

Method new()

Usage

Arguments

Method addAccessor()

Usage

Arguments

Returns

Method getScene()

Usage

Arguments

Returns

Method setScene()

Usage

Arguments

Method addScene()

Usage

Returns

Method addToScene()

Usage

Arguments

Method defaultScene()

Usage

Returns

Method getNode()

Usage

Arguments

Returns

Method setNode()

Usage

Arguments

Method addNode()

Usage

Arguments

Returns

Method addChild()

Usage

Arguments

Method setParents()

Usage

Method getSkin()

Usage

Arguments

Returns

Method setSkin()

Usage

Arguments

Method getJoint()

Usage

Arguments

Returns

Method getInverseBindMatrices()

Usage

Arguments

Returns

Method getForwardBindMatrices()

Usage

Arguments

Returns

Method getCamera()

Usage

Arguments

Returns

Method getExtras()

Usage

Returns

Method setExtras()

Usage

Arguments

Method getMesh()

Usage

Arguments

Returns

Method setMesh()

Usage

Arguments

Method `new()`

Method `addAccessor()`

Method `getScene()`

Method `setScene()`

Method `addScene()`

Method `addToScene()`

Method `defaultScene()`

Method `getNode()`

Method `setNode()`

Method `addNode()`

Method `addChild()`

Method `setParents()`

Method `getSkin()`

Method `setSkin()`

Method `getJoint()`

Method `getInverseBindMatrices()`

Method `getForwardBindMatrices()`

Method `getCamera()`

Method `getExtras()`

Method `setExtras()`

Method `getMesh()`

Method `setMesh()`

Method `addMesh()`

Method `getMaterial()`

Method `getTexture()`

Method `getImage()`

Method `addMaterial()`

Method `addTexture()`

Method `addImage()`

Method `addSampler()`

Method `getMaterialNumber()`

Method `writeVectors()`

Method `makePrimitive()`

Method `getAsset()`

Method `setAsset()`

Method `getTransform()`

Method `getRglMaterial()`

Method `getAnimation()`

Method `setAnimation()`

Method `timerange()`

Method `initAnimation()`