R: Get information about shapes

rgl.attrib {rgl} | R Documentation

## Get information about shapes

### Description

Retrieves information about the shapes in a scene.

### Usage

    rgl.attrib(id, attrib, first = 1,
    	last = rgl.attrib.count(id, attrib))

### Arguments

`id` | A shape identifier, as returned by `rgl.ids`.
`attrib` | An attribute of a shape. Currently supported: one of `"vertices"`, `"normals"`, `"colors"`, `"texcoords"`, `"dim"`, `"texts"`, `"cex"`, `"adj"`, `"radii"`, `"centers"`, `"ids"`, `"usermatrix"`, `"types"`, `"flags"`, `"offsets"`, `"family"`, `"font"` or unique prefixes to one of those.
`first, last` | Specify these to retrieve only those rows of the result.

### Details

If the identifier is not found or is not a shape that has the given attribute, zero will be returned by `rgl.attrib.count`, and an empty matrix will be returned by `rgl.attrib`.

The first four `attrib` names correspond to the usual OpenGL properties; `"dim"` is used just for surfaces, defining the rows and columns in the rectangular grid; `"cex"`, `"adj"`, `"family"` and `"font"` apply only to text objects.

### Value

`rgl.attrib` returns the values of the attribute. Attributes are mostly real-valued, with the following sizes:

`"vertices"` | 3 values | x, y, z
`"normals"` | 3 values | x, y, z
`"centers"` | 3 values | x, y, z
`"colors"` | 4 values | r, g, b, a
`"texcoords"` | 2 values | s, t
`"dim"` | 2 values | r, c
`"cex"` | 1 value | cex
`"adj"` | 2 values | x, y
`"radii"` | 1 value | r
`"ids"` | 1 value | id
`"usermatrix"` | 4 values | x, y, z, w
`"texts"` | 1 value | text
`"types"` | 1 value | type
`"flags"` | 1 value | flag
`"family"` | 1 value | family
`"font"` | 1 value | font

The `"texts"`, `"types"` and `"family"` attributes are character-valued; the `"flags"` attribute is logical valued, with named rows.

These are returned as matrices with the row count equal to the count for the attribute, and the columns as listed above.

### Author(s)

Duncan Murdoch

### See Also

`rgl.ids`, `rgl.attrib.info`

### Examples

    p <- plot3d(rnorm(100), rnorm(100), rnorm(100), type = "s", col = "red")
    rgl.attrib(p["data"], "vertices", last = 10)

[Package rgl version 0.99.9 Index]