Function gmtplot_z_gridlines

src/gmt_plot.c:1912–1968

}

GMT_LOCAL void gmtplot_z_gridlines (struct GMT_CTRL *GMT, struct PSL_CTRL *PSL, double zmin, double zmax, int plane, unsigned int mode3d, int quadrant) {
	unsigned int k, i, nz, n, item[2] = {GMT_GRID_UPPER, GMT_GRID_LOWER};
	int qplane = 1 - plane;
	double dz, zz, dd, min, max, z0, z1, xx, dummy, value, *z = NULL, *d = NULL;
	char *plane_name[2] = {"y-z", "x-z"};

	if (qplane == GMT_X) {
		value = (quadrant == 4) ? GMT->common.R.wesn[YHI] : GMT->common.R.wesn[YLO];
		min = GMT->current.proj.rect[XLO];	max = GMT->current.proj.rect[XHI];
	}
	else {
		value = (quadrant == 3) ? GMT->common.R.wesn[XHI] : GMT->common.R.wesn[XLO];
		min = GMT->current.proj.rect[YLO];	max = GMT->current.proj.rect[YHI];
	}

	for (k = 0; k < 2; k++) {
		if (fabs (GMT->current.setting.map_grid_cross_size[k]) > 0.0) continue;

		dz = gmtlib_get_map_interval (GMT, GMT->current.map.frame.axis[GMT_Z].type, &GMT->current.map.frame.axis[GMT_Z].item[item[k]]);	/* Gridline spacing in z */

		if (!GMT->current.map.frame.axis[GMT_Z].item[item[k]].active || fabs(dz) == 0.0) continue;

		PSL_comment (PSL, "%s gridlines %s\n", plane_name[plane], k ? "(secondary)" : "(primary)");

		gmt_setpen (GMT, &GMT->current.setting.map_grid_pen[k]);

		nz = gmtlib_coordinate_array (GMT, zmin, zmax, &GMT->current.map.frame.axis[GMT_Z].item[item[k]], &z, NULL);
		for (i = 0; i < nz; i++) {	/* Here z acts as y and x|y acts as x */
			/* Draw one horizontal line */
			zz = gmt_z_to_zz (GMT, z[i]);
			PSL_plotsegment (PSL, min, zz, max, zz);
		}
		z0 = gmt_z_to_zz (GMT, zmin);	/* These are the projected min and max z values, i.e., the ends of vertical gridlines on the back walls */
		z1 = gmt_z_to_zz (GMT, zmax);

		dd = gmtlib_get_map_interval (GMT, GMT->current.map.frame.axis[qplane].type, &GMT->current.map.frame.axis[qplane].item[item[k]]);
		if (!GMT->current.map.frame.axis[qplane].item[item[k]].active || fabs(dd) == 0.0) continue;
		n = gmtlib_coordinate_array (GMT, GMT->common.R.wesn[2*qplane], GMT->common.R.wesn[2*qplane+1], &GMT->current.map.frame.axis[qplane].item[item[k]], &d, NULL);
		for (i = 0; i < n; i++) {	/* Here z acts as y and x|y acts as x */
			/* Draw one horizontal line */
			if (qplane == GMT_X)	/* The "x" are projection x or longitude */
				gmt_geo_to_xy (GMT, d[i], value, &xx, &dummy);
			else	/* The "x" are projection y or latitude */
				gmt_geo_to_xy (GMT, value, d[i], &dummy, &xx);

			PSL_plotsegment (PSL, xx, z0, xx, z1);
		}
		gmt_M_free (GMT, d);

		PSL_setdash (PSL, NULL, 0);
	}
	if (!GMT->current.map.frame.draw_wall && z && (mode3d & GMT_3D_BOX) == 0) {
		PSL_plotsegment (PSL, min, z0, min, z1);
		PSL_plotsegment (PSL, max, z0, max, z1);
	}
	gmt_M_free (GMT, z);
}