DRAWING_MODE(3G)

NAME

drawing_mode − select the pixel replacement rules for subsequent raster operations and output primitives.

SYNOPSIS

C Syntax:

void drawing_mode(fildes,replacement_rule);
int fildes,replacement_rule;

FORTRAN77 Syntax:

subroutine drawing_mode(fildes,replacement_rule)
integer*4 fildes,replacement_rule

Pascal Syntax:

procedure drawing_mode(fildes,replacement_rule:integer);

DESCRIPTION

Input Parameters

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

replacement_rule
Defines the combination of source and destination pixel values:

    ReplacementResulting Destination Value
   Rules
     0       ZERO
    1       Source AND Destination
    2       Source AND NOT Destination
    3       Source (the default rule)
    4       NOT Source AND Destination
    5       Destination
    6       Source EXCLUSIVE OR Destination
    7       Source OR Destination
    8       NOT source AND NOT Destination
    9       Source EXCLUSIVE NOR Destination
   10       NOT Destination
   11       Source OR NOT Destination
   12       NOT Source
   13       NOT Source OR Destination
   14       NOT Source OR NOT Destination
   15       ONE

Discussion

Drawing_mode sets the replacement rule used by both the raster operation functions and all the output primitives.

This procedure only applies to raster devices. Some raster devices may not support all drawing modes.

DEFAULTS

Replacement_rule = 3 (source).

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