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- /* $Id: x16c.c,v 1.4 1994/06/30 17:57:58 mjl Exp $
- * $Log: x16c.c,v $
- * Revision 1.4 1994/06/30 17:57:58 mjl
- * All C example programs: made another pass to eliminate warnings when using
- * gcc -Wall. Lots of cleaning up: got rid of includes of math.h or string.h
- * (now included by plplot.h), eliminated redundant casts, put in more
- * uniform comments, and other minor changes.
- *
- * Revision 1.3 1994/04/25 19:02:55 mjl
- * Increased the number of shade regions to make it a bit more interesting
- * when playing with the palette.
- *
- * Revision 1.2 1994/04/08 12:08:21 mjl
- * Cleaned up some, switched to more interesting test function.
- *
- * Revision 1.1 1994/03/30 07:22:55 mjl
- * Added to test specifically color fill capability of plshade, with optional
- * coordinate mapping.
- */
-
- /* x16c.c
-
- plshade demo, using color fill.
-
- Maurice LeBrun
- IFS, University of Texas at Austin
- 20 Mar 1994
- */
-
- #include <plplot.h>
-
- #define NCONTR 30 /* Number of contours */
- #define XPTS 35 /* Data points in x */
- #define YPTS 46 /* Datat points in y */
-
- #define XSPA 2./(XPTS-1)
- #define YSPA 2./(YPTS-1)
-
- static PLFLT clevel[NCONTR];
-
- /* Utility macros */
-
- #ifndef PI
- #define PI 3.1415926535897932384
- #endif
- #ifndef MAX
- #define MAX(a,b) (((a) > (b)) ? (a) : (b))
- #endif
- #ifndef MIN
- #define MIN(a,b) (((a) < (b)) ? (a) : (b))
- #endif
-
- /* Transformation function */
-
- PLFLT tr[6] =
- {XSPA, 0.0, -1.0, 0.0, YSPA, -1.0};
-
- static void
- mypltr(PLFLT x, PLFLT y, PLFLT *tx, PLFLT *ty, void *pltr_data)
- {
- *tx = tr[0] * x + tr[1] * y + tr[2];
- *ty = tr[3] * x + tr[4] * y + tr[5];
- }
-
- /* Function prototypes */
-
- static void
- f2mnmx(PLFLT **f, PLINT nx, PLINT ny, PLFLT *fmin, PLFLT *fmax);
-
- /*----------------------------------------------------------------------*\
- * main
- *
- * Does several shade plots using different coordinate mappings.
- \*----------------------------------------------------------------------*/
-
- int
- main(int argc, char *argv[])
- {
- int i, j;
- PLFLT x, y, argx, argy, distort;
-
- PLFLT **z, **w, zmin, zmax;
- PLFLT xg1[XPTS], yg1[YPTS];
- PLcGrid cgrid1;
- PLcGrid2 cgrid2;
-
- PLFLT shade_min, shade_max, sh_color;
- PLINT sh_cmap = 1, sh_width;
- PLINT min_color = 1, min_width = 0, max_color = 0, max_width = 0;
-
- /* Parse and process command line arguments */
-
- (void) plParseInternalOpts(&argc, argv, PL_PARSE_FULL);
-
- /* Reduce colors in cmap 0 so that cmap 1 is useful on a 16-color display */
-
- plscmap0n(3);
-
- /* Initialize plplot */
-
- plinit();
-
- /* Set up function arrays */
-
- plAlloc2dGrid(&z, XPTS, YPTS);
- plAlloc2dGrid(&w, XPTS, YPTS);
-
- /* Set up data array */
-
- for (i = 0; i < XPTS; i++) {
- x = (double) (i - (XPTS / 2)) / (double) (XPTS / 2);
- for (j = 0; j < YPTS; j++) {
- y = (double) (j - (YPTS / 2)) / (double) (YPTS / 2) - 1.0;
-
- z[i][j] = - sin(7.*x) * cos(7.*y) + x*x - y*y;
- w[i][j] = - cos(7.*x) * sin(7.*y) + 2 * x * y;
- }
- }
- f2mnmx(z, XPTS, YPTS, &zmin, &zmax);
- for (i = 0; i < NCONTR; i++)
- clevel[i] = zmin + (zmax - zmin) * (i + 0.5) / (float) NCONTR;
-
- /* Set up coordinate grids */
-
- cgrid1.xg = xg1;
- cgrid1.yg = yg1;
- cgrid1.nx = XPTS;
- cgrid1.ny = YPTS;
-
- plAlloc2dGrid(&cgrid2.xg, XPTS, YPTS);
- plAlloc2dGrid(&cgrid2.yg, XPTS, YPTS);
- cgrid2.nx = XPTS;
- cgrid2.ny = YPTS;
-
- for (i = 0; i < XPTS; i++) {
- for (j = 0; j < YPTS; j++) {
- mypltr((PLFLT) i, (PLFLT) j, &x, &y, NULL);
-
- argx = x * PI/2;
- argy = y * PI/2;
- distort = 0.4;
-
- cgrid1.xg[i] = x + distort * cos(argx);
- cgrid1.yg[j] = y - distort * cos(argy);
-
- cgrid2.xg[i][j] = x + distort * cos(argx) * cos(argy);
- cgrid2.yg[i][j] = y - distort * cos(argx) * cos(argy);
- }
- }
-
- /* Plot using identity transform */
-
- pladv(0);
- plvpor(0.1, 0.9, 0.1, 0.9);
- plwind(-1.0, 1.0, -1.0, 1.0);
-
- for (i = 0; i < NCONTR; i++) {
- shade_min = zmin + (zmax - zmin) * i / (float) NCONTR;
- shade_max = zmin + (zmax - zmin) * (i +1) / (float) NCONTR;
- sh_color = i / (float) (NCONTR-1);
- sh_width = 2;
- plpsty(0);
-
- plshade(z, XPTS, YPTS, NULL, -1., 1., -1., 1.,
- shade_min, shade_max,
- sh_cmap, sh_color, sh_width,
- min_color, min_width, max_color, max_width,
- plfill, 1, NULL, NULL);
- }
-
- plcol(1);
- plbox("bcnst", 0.0, 0, "bcnstv", 0.0, 0);
- plcol(2);
- /*
- plcont(w, XPTS, YPTS, 1, XPTS, 1, YPTS, clevel, NCONTR, mypltr, NULL);
- */
- pllab("distance", "altitude", "Bogon density");
-
- /* Plot using 1d coordinate transform */
-
- pladv(0);
- plvpor(0.1, 0.9, 0.1, 0.9);
- plwind(-1.0, 1.0, -1.0, 1.0);
-
- for (i = 0; i < NCONTR; i++) {
- shade_min = zmin + (zmax - zmin) * i / (float) NCONTR;
- shade_max = zmin + (zmax - zmin) * (i +1) / (float) NCONTR;
- sh_color = i / (float) (NCONTR-1);
- sh_width = 2;
- plpsty(0);
-
- plshade(z, XPTS, YPTS, NULL, -1., 1., -1., 1.,
- shade_min, shade_max,
- sh_cmap, sh_color, sh_width,
- min_color, min_width, max_color, max_width,
- plfill, 1, pltr1, (void *) &cgrid1);
- }
-
- plcol(1);
- plbox("bcnst", 0.0, 0, "bcnstv", 0.0, 0);
- plcol(2);
- /*
- plcont(w, XPTS, YPTS, 1, XPTS, 1, YPTS, clevel, NCONTR,
- pltr1, (void *) &cgrid1);
- */
- pllab("distance", "altitude", "Bogon density");
-
- /* Plot using 2d coordinate transform */
-
- pladv(0);
- plvpor(0.1, 0.9, 0.1, 0.9);
- plwind(-1.0, 1.0, -1.0, 1.0);
-
- for (i = 0; i < NCONTR; i++) {
- shade_min = zmin + (zmax - zmin) * i / (float) NCONTR;
- shade_max = zmin + (zmax - zmin) * (i +1) / (float) NCONTR;
- sh_color = i / (float) (NCONTR-1);
- sh_width = 2;
- plpsty(0);
-
- plshade(z, XPTS, YPTS, NULL, -1., 1., -1., 1.,
- shade_min, shade_max,
- sh_cmap, sh_color, sh_width,
- min_color, min_width, max_color, max_width,
- plfill, 0, pltr2, (void *) &cgrid2);
- }
-
- plcol(1);
- plbox("bcnst", 0.0, 0, "bcnstv", 0.0, 0);
- plcol(2);
-
- plcont(w, XPTS, YPTS, 1, XPTS, 1, YPTS, clevel, NCONTR,
- pltr2, (void *) &cgrid2);
-
- pllab("distance", "altitude", "Bogon density, with streamlines");
-
- /* Clean up */
-
- plend();
- free((void *) w);
- free((void *) z);
- exit(0);
- }
-
- /*----------------------------------------------------------------------*\
- * f2mnmx
- *
- * Returns min & max of input 2d array.
- \*----------------------------------------------------------------------*/
-
- static void
- f2mnmx(PLFLT **f, PLINT nx, PLINT ny, PLFLT *fmin, PLFLT *fmax)
- {
- int i, j;
-
- *fmax = f[0][0];
- *fmin = *fmax;
-
- for (i = 0; i < nx; i++) {
- for (j = 0; j < ny; j++) {
- *fmax = MAX(*fmax, f[i][j]);
- *fmin = MIN(*fmin, f[i][j]);
- }
- }
- }
-