MATLAB Function Reference

alpha

Set transparency properties for objects in current axes

Syntax

• alpha(face_alpha)
  alpha(alpha_data)
  alpha(alpha_data_mapping)
  alpha(object_handle,...)
  

Description

alpha sets one of three transparency properties, depending on what arguments you specify with the call to this function.

FaceAlpha

alpha(face_alpha) set the FaceAlpha property of all image, patch, and surface objects in the current axes. You can set face_alpha to:

• a scalar - set the FaceAlpha property to the specified value (for images, set the AlphaData property to the specified value)
• 'flat' - set the FaceAlpha property to flat
• 'interp' - set the FaceAlpha property to interp
• 'texture' - set the FaceAlpha property to texture
• 'opaque' - set the FaceAlpha property to 1
• 'clear' - set the FaceAlpha property to 0

See Specifying a Single Transparency Value for more information.

AlphaData (Surface Objects)

alpha(alpha_data) sets the AlphaData property of all surface objects in the current axes. You can set alpha_data to:

• a matrix the same size as CData - sets the AlphaData property to the specified values
• 'x' - set the AlphaData property to be the same as XData
• 'y' - set the AlphaData property to be the same as YData
• 'z' - set the AlphaData property to be the same as ZData
• 'color' - set the AlphaData property to be the same as CData
• 'rand' - set the AlphaData property to a matrix of random values equal in size to CData

AlphaData (Image Objects)

alpha(alpha_data) sets the AlphaData property of all image objects in the current axes. You can set alpha_data to:

• a matrix the same size as CData - sets the AlphaData property to the specified value
• 'x' - ignored
• 'y' - ignored
• 'z' - ignored
• 'color' - set the AlphaData property to be the same as CData
• 'rand' - set the AlphaData property to a matrix of random values equal in size to CData

FaceVertexAlphaData (Patch Objects)

alpha(alpha_data) sets the FaceVertexAlphaData property of all patch objects in the current axes. You can set alpha_data to:

• a matrix the same size as FaceVertexCData - sets the FaceVertexAlphaData property to the specified value
• 'x' - set the FaceVertexAlphaData property to be the same as Vertices(:,1)
• 'y' - set the FaceVertexAlphaData property to be the same as Vertices(:,2)
• 'z' - set the FaceVertexAlphaData property to be the same as Vertices(:,3)
• 'color' - set the FaceVertexAlphaData property to be the same as FaceVertexCData
• 'rand' - set the FaceVertexAlphaData property to random values

See Mapping Data to Transparency for more information.

AlphaDataMapping

alpha(alpha_data_mapping) sets the AlphaDataMapping property of all image, patch, and surface objects in the current axes. You can set alpha_data_mapping to:

• 'scaled' - set the AlphaDataMapping property to scaled
• 'direct' - set the AlphaDataMapping property to direct
• 'none' - set the AlphaDataMapping property to none

alpha(object_handle,value) set the transparency property only on the object identified by object_handle

See Also

alim, alphamap

Image: AlphaData, AlphaDataMapping

Patch: FaceAlpha, FaceVertexAlphaData, AlphaDataMapping

Surface: FaceAlpha, AlphaData, AlphaDataMapping

Transparency for related functions

Transparency in 3-D Visualization for examples

allchild

alphamap