plscmap1a: Set semitransparent cmap1 RGBA colors.
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plscmap1a: Set semitransparent cmap1 RGBA colors.

plscmap1a ( r ,
  g ,
  b ,
  alpha ,
  ncol1 );
 

Set semitransparent cmap1 colors (see the section called “Color Map1”) using RGBA vector values. This function also sets the number of cmap1 colors. N.B. Continuous cmap1 colors are indexed with a floating-point index in the range from 0.0-1.0 which is linearly transformed (e.g., by plcol1) to an integer index of these RGBA vectors in the range from 0 to ncol1-1. So in order for this continuous color model to work properly, it is the responsibility of the user of plscmap1 to insure that these RGBA vectors are continuous functions of their integer indices.

r (PLINT_VECTOR, input)

A vector that represents (using unsigned 8-bit integers in the range from 0-255) the degree of red in the color as a continuous function of the integer index of the vector.

g (PLINT_VECTOR, input)

A vector that represents (using unsigned 8-bit integers in the range from 0-255) the degree of green in the color as a continuous function of the integer index of the vector.

b (PLINT_VECTOR, input)

A vector that represents (using unsigned 8-bit integers in the range from 0-255) the degree of blue in the color as a continuous function of the integer index of the vector.

alpha (PLFLT_VECTOR, input)

A vector that represents (using PLFLT values in the range from 0.0-1.0 where 0.0 corresponds to completely transparent and 1.0 corresponds to completely opaque) the alpha transparency of the color as a continuous function of the integer index of the vector.

ncol1 (PLINT, input)

Number of items in the r , g , b , and alpha vectors.

Redacted form: plscmap1a(r, g, b, alpha)

This function is used in example 31.

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plscmap1: Set opaque RGB cmap1 colors values  Home  plscmap1l: Set cmap1 colors using a piece-wise linear relationship