NAME

readRGB - returns values of specific pixels

SPECIFICATION

C
long readRGB(n, red, green, blue)
short n;
RGBvalue red[], green[], blue[];

FORTRAN
integer*4 function readRG(n, red, green, blue)
integer*4 n
character*(*) red, green, blue

Pascal
function readRGB(n: Short; var red, green, blue:
.B "RGBvalue): longint;"

DESCRIPTION

readRGB attempts to read up to n pixel values from the bitplanes.  They are read into the red, green, and blue arrays starting from the current character position along a single scan line (constant y) in the direction of increasing x.  readRGB returns the number of pixels actually read, which is only guaranteed to be the number requested if the starting point is at least that many away from the edge of the current viewport.  The values of pixels read outside the current viewport are undefined.  The current character position is updated to be one pixel to the right of the last one read, or is undefined if the new position is outside the viewport.  The IRIS must be in RGB mode for this command to work. 

SEE ALSO

readpixels, writeRGB

NOTE

This command can be used only in immediate mode. 

Version 2.4  —  May 08, 1986