yt.visualization.volume_rendering.transfer_functions.ColorTransferFunction.add_gaussian

ColorTransferFunction.add_gaussian(location, width, height)[source]

Add a Gaussian distribution to the transfer function.

Typically, when rendering isocontours, a Guassian distribution is the easiest way to draw out features. The spread provides a softness. The values are calculated as f(x) = h \exp{-(x-x_0)^2 / w}.

Parameters:

location : float

The centroid of the Gaussian (x_0 in the above equation.)

width : float

The relative width (w in the above equation.)

height : list of 4 float

The peak height (h in the above equation.) Note that while values greater 1.0 will be accepted, the values of the transmission function are clipped at 1.0. This must be a list, and it is in the order of (red, green, blue, alpha).

Examples

This adds a red spike.

>>> tf = ColorTransferFunction( (-10.0, -5.0) )
>>> tf.add_gaussian(-9.0, 0.01, [1.0, 0.0, 0.0, 1.0])