fsleyes.gl.textures.lookuptabletexture

This module provides the LookupTableTexture class, a 1D Texture which stores the colours of a LookupTable as an OpenGL texture.

class fsleyes.gl.textures.lookuptabletexture.LookupTableTexture(name)

Bases: fsleyes.gl.textures.texture.Texture

The LookupTableTexture class is a 1D Texture which stores the colours of a LookupTable as an OpenGL texture.

A LookupTable stores a collection of label values (assumed to be unsigned 16 bit integers), and colours associated with each label. This mapping of {label : colour} is converted into a numpy array of size \(max(labels)\times 3\) containing the lookup table, where a label value can be used as an array index to retrieve the corresponding colour. All aspects of a LookupTableTexture can be configured via the set() method.

As OpenGL textures are indexed by coordinates in the range [0.0, 1.0], you will need to divide label values by \(max(labels)\) to convert them into texture coordinates.

Note

Currently, the maximum label value in a lookup table cannot be greater than the maximum size of an OpenGL texture - this limit differs between platforms. In the future, if this class needs to be modified to support larger lookup tables, it will need to be changed to use a 2D texture, and users will need to ravel/unravel texture indices between 1D and 2D coordinates.

__init__(name)

Create a LookupTableTexture.

Parameters

name – A uniqe name for this LookupTableTexture.

set(**kwargs)

Set any parameters on this LookupTableTexture. Valid keyword arguments are:

lut	The LookupTable instance.
alpha	Transparency, a value between 0.0 and 1.0. Defaults to 1.0
brightness	Brightness, a value between 0.0 and 1.0. Defaults to 0.5.
contrast	Contrast, a value between 0.0 and 1.0. Defaults to 0.5.

refresh()

Forces a refresh of this LookupTableTexture. This method should be called when the LookupTable has changed, so that the underlying texture is kept consistent with it.

_LookupTableTexture__refresh(*a)

Configures the underlying OpenGL texture.

__module__ = 'fsleyes.gl.textures.lookuptabletexture'