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) sets 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 -- Set 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 -- Set 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 -- Set 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) sets 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

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