allbery@uunet.UU.NET (Brandon S. Allbery - comp.sources.misc) (01/30/89)
Posting-number: Volume 6, Issue 14
Submitted-by: jeff@ddsw1.MCS.COM (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/* jeff@ddsw1.mcs.com 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