Usenet 1994 October/usenetsourcesnewsgroupsinfomagicoctober1994disk2.iso/misc/volume6/liss

Internet Message Format | 1989-02-03 | 6KB

Path: xanth!nic.MR.NET!csd4.milw.wisc.edu!leah!itsgw!steinmetz!uunet!allbery
From: [e-mail] (Brandon S. Allbery - comp.sources.misc)
Newsgroups: comp.sources.misc
Subject: v06i014: liss - draw Lissajous figures on a Sun
Message-ID: <[e-mail]>
Date: 29 Jan 89 20:24:15 GMT
Sender: [e-mail]
Reply-To: [e-mail] (Jeff Haferman)
Distribution: na
Organization: ddsw1.MCS.COM, Mundelein, IL
Lines: 207
Approved: [e-mail] (Brandon S. Allbery - comp.sources.misc)

Posting-number: Volume 6, Issue 14
Submitted-by: [e-mail] (Jeff Haferman)
Archive-name: liss

[I had to "shar" this.  ++bsa]

The following program is something I adapted from an APL program
used as an example by the Professor of a Graphics course I took
last year.  I put it together to begin experimenting with Sunview
programming, so this is a first for me.  There are a couple of
sloppy things, but as far as I can tell, it should work on all
Suns, though I've only tested it on a 3/50.  Also, it should be
easy to port to any machine (I know a Macintosh port would be
simple.)

Anyway, this is a starting point for me to get more into Sun
programming.  Enjoy.

----------cut here---------cut here-----------cut here-----------cut here----
#! /bin/sh
# This file was wrapped with "dummyshar".  "sh" this file to extract.
# Contents:  liss.c
echo extracting 'liss.c'
if test -f 'liss.c' -a -z "$1"; then echo Not overwriting 'liss.c'; else
sed 's/^X//' << \EOF > 'liss.c'
X/*********************************************************************/
X/*                              liss                                 */
X/*      Purpose : Visual entertainment on a Sun.  Displays a         */
X/*                "Lissajous" figure, which is the connection        */
X/*                of points { cos(2*PI*x*i/n), sin(2*PI*y*i/n) }     */
X/*                for i=0,1,2,...,n and suitably chosen positive     */
X/*                integers x,y, and n.  Must use SunView.            */
X/*                                                                   */
X/*      Org :  Jeff Haferman 12/27/88                                */
X/*             [e-mail]  or ...!oddjob!ddsw1.mcs.com!jeff  */
X/*                                                                   */
X/*      Compile:                                                     */
X/*            cc liss.c -o liss -lsuntool -lsunwindow -lpixrect -lm  */
X/*                                                                   */
X/*      Sample:                                                      */
X/*            liss 100 200 359                                       */
X/*                                                                   */
X/*********************************************************************/
X
X#include <suntool/sunview.h>
X#include <suntool/canvas.h>
X#include <stdio.h>
X#include <math.h>
X
X#define X 1
X#define Y 2
X#define TRUE 1
X#define FALSE 0
X#define MAT(a) ((float *) a)
X
Xchar *progname;
X
Xmain (argc, argv)
Xchar **argv;
Xint argc;
X{
X    Frame frame;
X    Canvas canvas;
X    Pixwin *pw;
X    int x,y,n,i;
X    int plotx, ploty, plotx_last, ploty_last;
X    double dblx, dbly;
X    int first_pass=TRUE;
X    int width, height;
X    static float r2sun[3][3];
X    float *plot, *transform();
X
X    progname=argv[0];
X    if ( argc != 4 )
X        usage();
X
X    x= char2num(argv[1]);
X    y= char2num(argv[2]);
X    n= char2num(argv[3]);
X
X    frame = window_create(NULL, FRAME, 0);
X    canvas = window_create(frame, CANVAS,
X        CANVAS_FIXED_IMAGE, FALSE,
X        0);
X    pw= canvas_pixwin(canvas);
X
X    width = ((int) window_get(canvas, CANVAS_WIDTH))-1;
X    height = ((int) window_get(canvas, CANVAS_HEIGHT))-1;
X    get_transform(width,height,r2sun);
X
X    for (i=0; i<=n; i++) {
X        plotx_last = plotx;
X        ploty_last = ploty;
X        dblx = cos ((double)(2*M_PI*x*((float)i/(float)n)));
X          dbly = sin ((double)(2*M_PI*y*((float)i/(float)n)));
X          plot = transform((float)dblx,(float)dbly,r2sun);
X          plotx = (int) plot[X-1];
X          ploty = (int) plot[Y-1];
X        if (!first_pass)
X            pw_vector(pw,plotx_last,ploty_last,plotx,ploty,PIX_SRC,1);
X        else
X            first_pass=FALSE;
X    }
X
X    window_main_loop(frame);
X    exit(0);
X}
X
X
Xget_transform(w,h,tranmat)
X    int w,h;
X    float *tranmat;
X{
Xint i,j;
X    float w0,w1,h0,h1;
X    static float a[3][3]= { {-1,0,1},
X                             {-1,1,0},
X                             {1,0,0}};
X    static float b[3][3]= { {0,0,1},
X                             {0,0,1},
X                             {0,0,1}};
X    w0=(float)w;
X    w1=w0/2;
X    h0=(float)h;
X    h1=h0/2;
X
X    b[0][0]=w1;
X    b[0][1]=h1;
X    b[1][0]=w1;
X    b[2][0]=w0;
X    b[2][1]=h1;
X
X    m_mult(a,b,tranmat,3,3,3);
X}
X
X
Xfloat
X*transform(x,y,tranmat)
X    float x,y,*tranmat;
X{
Xint j;
X    static float a[3]={0,0,1};
X    float b[3];
X
X    a[0]=x;
X    a[1]=y;
X    m_mult(a,tranmat,b,1,3,3);
X
X    return(b);
X}
X
X
X/*------------------------------------------------------------*/
X/*                                                            */
X/*   m_mult(A,B,C,m,n,p)                                      */
X/*          A is  an (m x n) matrix of floats                 */
X/*          B is  an (n x p) matrix of floats                 */
X/*          C is  an (m x p) matrix of floats                 */
X/*                                                            */
X/*    A and B must be set before the call.  C is then set     */
X/*    here as the product of A and B.  No checking is done    */
X/*    here on the dimensions of A and B.                      */
X/*                                                            */
X/*------------------------------------------------------------*/
X
Xm_mult(A,B,C,m,n,p)
X    float **A, **B, **C;
X    int    m, n, p;
X
X/* for a good explantion on passing arbitrary sized matrices
X   to functions, see pp. 119-121 in C++                       */
X
X{
X    int i, j, k;
X
X    for(i=0; i<=m-1; i++)
X        for(j=0; j<=p-1; j++) {
X            MAT(C)[i*p+j]=0;
X            for(k=0; k<=n-1; k++)
X                MAT(C)[i*p+j]+= ( MAT(A)[i*n+k] * MAT(B)[k*p+j] );
X        }
X}
X
Xchar2num(c)
X    char *c;
X{
X    int i;
X
X    for (i = 0; *c >= '0' && *c <= '9'; c++)
X        i *= 10, i += *c - '0';
X    if (*c)
X        usage();
X    return (i);
X}
X
X
Xusage()
X{
X    fprintf(stderr, "usage: %s \<x\> \<y\> \<n\>\n", progname);
X    fprintf(stderr, "       where x, y, and n are positive integers.");
X    exit(1);
X}
EOF
chars=`wc -c < 'liss.c'`
if test $chars !=     4785; then echo 'liss.c' is $chars characters, should be     4785 characters!; fi
fi
exit 0