.\" Copyright (c) 1980, 1993.\"	The Regents of the University of California.  All rights reserved..\".\" Redistribution and use in source and binary forms, with or without.\" modification, are permitted provided that the following conditions.\" are met:.\" 1. Redistributions of source code must retain the above copyright.\"    notice, this list of conditions and the following disclaimer..\" 2. Redistributions in binary form must reproduce the above copyright.\"    notice, this list of conditions and the following disclaimer in the.\"    documentation and/or other materials provided with the distribution..\" 3. All advertising materials mentioning features or use of this software.\"    must display the following acknowledgement:.\"	This product includes software developed by the University of.\"	California, Berkeley and its contributors..\" 4. Neither the name of the University nor the names of its contributors.\"    may be used to endorse or promote products derived from this software.\"    without specific prior written permission..\".\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION).\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF.\" SUCH DAMAGE..\".\"	@(#)appen.C	8.1 (Berkeley) 6/8/93.\".ie t .oh '\*(Ln Appendix A''PS1:19-%'.eh 'PS1:19-%''\*(Ln Appendix A'.el .he ''\fIAppendix A\fR''.bp.(x.ti 0.b "Appendix A".)x.sh 1 "Examples" 1.ppHere we present a few examplesof how to use the package.They attempt to be representative,though not comprehensive.  Further examples can be found in the games sectionof the source tree and in various utilities that use the screen such as .i systat(1) ..sh 2 "Screen Updating".ppThe following examples are intended to demonstratethe basic structure of a programusing the screen updating sections of the package.Several of the programs require calculational sectionswhich are irrelevant of to the example,and are therefore usually not included.It is hoped that the data structure definitionsgive enough of an idea to allow understandingof what the relevant portions do..sh 3 "Simple Character Output".ppThis program demonstrates how to set up a window and output characters to it.Also, it demonstrates how one might control the output to the window.  Ifyou run this program, you will get a demonstration of the character outputchracteristics discussed in the above Character Output section..(l I.so t2.gr.)l.sh 3 "A Small Screen Manipulator".ppThe next example follows the lines of the previous one but extends then to demonstrate the various othe uses of the package.  Make sure you understand how this program works as it encompasses most of anything you willneed to do with the package..(l I.so t3.gr.)l.sh 3 "Twinkle".ppThis is a moderately simple program which printspatterns on the screen.It switches between patterns of asterisks,putting them on one by one in random order,and then taking them off in the same fashion.It is more efficient to write thisusing only the motion optimization,as is demonstrated below..(l I.so twinkle1.gr.)l.sh 3 "Life".ppThis program fragment models the famous computer pattern game of life(Scientific American, May, 1974).The calculational routines create a linked list of structuresdefining where each piece is.Nothing here claims to be optimal,merely demonstrative.This code, however,is a very good place to use the screen updating routines,as it allows them to worry about what the last position looked like,so you don't have to.It also demonstrates some of the input routines..(l I.so life.gr.)l.sh 2 "Motion optimization".ppThe following example shows how motion optimizationis written on its own.Programs which flit from one place to another withoutregard for what is already thereusually do not need the overhead of both space and timeassociated with screen updating.They should instead use motion optimization..sh 3 "Twinkle".ppThe.b twinkleprogramis a good candidate for simple motion optimization.Here is how it could be written(only the routines that have been changed are shown):.(l.so twinkle2.gr.)l