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/*
* example1.c: oscillating mesh
*
* This example module is distributed with the geomview manual.
* If you are not reading this in the manual, see the "External
* Modules" chapter of the manual for more details.
*
* This module creates an oscillating mesh.
*/
#include <math.h>
#include <stdio.h>
/* F is the function that we plot
*/
float F(x,y,t)
float x,y,t;
{
float r = sqrt(x*x+y*y);
return(sin(r + t)*sqrt(r));
}
main(argc, argv)
char **argv;
{
int xdim, ydim;
float xmin, xmax, ymin, ymax, dx, dy, t, dt;
xmin = ymin = -5; /* Set x and y */
xmax = ymax = 5; /* plot ranges */
xdim = ydim = 24; /* Set x and y resolution */
dt = 0.1; /* Time increment is 0.1 */
/* Geomview setup. We begin by sending the command
* (geometry example { : foo})
* to geomview. This tells geomview to create a geom called
* "example" which is an instance of the handle "foo".
*/
printf("(geometry example { : foo })\n");
fflush(stdout);
/* Loop until killed.
*/
for (t=0; ; t+=dt) {
UpdateMesh(xmin, xmax, ymin, ymax, xdim, ydim, t);
}
}
/* UpdateMesh sends one mesh iteration to geomview. This consists of
* a command of the form
* (read geometry { define foo
* MESH
* ...
* })
* where ... is the actual data of the mesh. This command tells
* geomview to make the value of the handle "foo" be the specified
* mesh.
*/
UpdateMesh(xmin, xmax, ymin, ymax, xdim, ydim, t)
float xmin, xmax, ymin, ymax, t;
int xdim, ydim;
{
int i,j;
float x,y, dx,dy;
dx = (xmax-xmin)/(xdim-1);
dy = (ymax-ymin)/(ydim-1);
printf("(read geometry { define foo \n");
printf("MESH\n");
printf("%1d %1d\n", xdim, ydim);
for (j=0, y = ymin; j<ydim; ++j, y += dy) {
for (i=0, x = xmin; i<xdim; ++i, x += dx) {
printf("%f %f %f\t", x, y, F(x,y,t));
}
printf("\n");
}
printf("})\n");
fflush(stdout);
}
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