ncl_hlsrgb man page

HLSRGB — Converts a color specification given as Hue, Lightness, and Saturation (HLS) values to Red, Green, and Blue (RGB) intensity values.

Synopsis

CALL HLSRGB ( H, L, S, R, G, B )

C-Binding Synopsis

#include <ncarg/ncargC.h>

void c_hlsrgb (float h, float l, float s, float *r,
float *g, float *b)

Description

H

(REAL, input, range [0.,360.) ) represents the hue of the input color in HLS color space. H=0. corresponds to blue.

L

(REAL, input, range [0.,100.])  represents the lightness value of the input color in HLS color space.  Lightness is a measure of the quantity of light - a lightness of 0. is black, and a lightness of 100. gives white. The pure hues occur at lightness value 50.

S

(REAL, input, range [0.,100.])  represents the saturation value of the input color in HLS color space.  Saturation is a measure of how much white light is mixed with the color. Colors having a saturation value of 0. represent grays with a gray intensity value equal to the lightness L.  Colors with a saturation value of 100. are fully saturated colors. The hue is undefined when S=0.  The fully saturated pure hues occur when S=100.  and L=50.

R

(REAL, output, range [0.,1.])  represents the red intensity component of the output color in RGB color space.

G

(REAL, output, range [0.,1.])  represents the green intensity component of the output color in RGB color space.

B

(REAL, output, range [0.,1.])  represents the blue intensity component of the output color in RGB color space.

C-Binding Description

The C-binding argument descriptions are the same as the FORTRAN  argument descriptions.

Examples

Use the ncargex command to see the following relevant examples:  ccpcldm, ccplbam, ccpllb, ccplll, ccpllw, colcon, fcce02.

Access

To use HLSRGB or c_hlsrgb, load the NCAR Graphics libraries ncarg, ncarg_gks, and ncarg_c, preferably in that order.  

Messages

See the colconv man page for a description of all Colconv error messages and/or informational messages.

See Also

Online: colconv, hlsrgb, hsvrgb, rgbhls, rgbhsv, rgbyiq, yiqrgb, ncarg_cbind.

Hardcopy: NCAR Graphics Fundamentals, UNIX Version

Info

March 1993 UNIX NCAR GRAPHICS