procedure sbfbkg

Sets the shading for the background. This routine should be called after SBFINT, and COLINT or COLTAB, but before any objects are plotted.

Syntax
sbfbkg IC1,IC2,ISHADE

Arguments

ARGUMENT    TYPE I/O DIMENSION DESCRIPTION

IC1,IC2:   I*4 I - Lowest & highest colour-index to be

   used for the shading.

ISHADE:   I*4 I - Order of shading (IC1-->IC2 - IC1):

   1 - Bottom to top.

   2 - Left to right.

   3 - Bottom-left to top-right.

   4 - Top-left to bottom-right.

   5 - Bottom, middle and top.

   6 - Left, middle and right.

   7 - Rectangular zoom to centre.

   8 - Elliptical zoom to centre.

ARGUMENT	TYPE I/O DIMENSION DESCRIPTION
IC1,IC2:	I*4 I - Lowest & highest colour-index to be
	used for the shading.
ISHADE:	I*4 I - Order of shading (IC1-->IC2 - IC1):
	1 - Bottom to top.
	2 - Left to right.
	3 - Bottom-left to top-right.
	4 - Top-left to bottom-right.
	5 - Bottom, middle and top.
	6 - Left, middle and right.
	7 - Rectangular zoom to centre.
	8 - Elliptical zoom to centre.