SHADE_RANGE(3G)

NAME

shade_range − set intensity-to-frame-buffer-index mapping

SYNOPSIS

C Syntax:

void shade_range(fildes,min,max);
int fildes,min,max;

FORTRAN77 Syntax:

subroutine shade_range(fildes,min,max)
integer*4 fildes,min,max

Pascal Syntax:

procedure shade_range(fildes,min,max:integer);

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by open when an I/O path to a graphics device is opened.

min Frame buffer index that intensity 0.0 maps to.

max Frame buffer index that intensity 1.0 maps to.

Discussion

When CMAP_MONOTONIC is specified in shade_mode the red, green, blue values are converted to an intensity, then mapped into the frame buffer using min and max . The min value must be less than the max value. It is left to the user to make sure the color map is set up in a monotonically increasing intensity between the two values. See shade_mode(3G) for the formula used to convert red,green,blue values to intensity.

DEFAULTS

min = 0; max is set to highest available index value.

Museum