static
void label_line(int n, double *xpts, double *ypts, double *zpts, char *label)
{
int i, j, k;
int error_ind;
int n_pts;
double dist;
double r_sqr;
double a, b, c;
double ox, oy;
double dx, dy, t;
double xtpt1, ytpt1, xtpt2, ytpt2;
double cpx, cpy, tx[4], ty[4];
double x_up_val, y_up_val;
double x_text_pos, y_text_pos;
double d, e;
/*--------------------------------------------------------------------------
/ Find out how large the label is so we will know how much room to leave
/ for it.
/-------------------------------------------------------------------------*/
x_up_val = 0.0;
y_up_val = 1.0;
gks_set_text_upvec(x_up_val, y_up_val);
d = 0.0;
e = 0.0;
gks_select_xform(contour_vars.ndc);
gks_inq_text_extent(contour_vars.wkid, d, e, label,
&error_ind, &cpx, &cpy, tx, ty);
gks_select_xform(contour_vars.tnr);
a = (tx[2] - tx[0]) / contour_vars.scale_factor;
b = (ty[2] - ty[0]) / contour_vars.scale_factor;
r_sqr = (a * a + b * b) / 4.0; /* Gap in line reduced to half size */
/*--------------------------------------------------------------------------
/ Try to find a good place to put the label on the contour line.
/-------------------------------------------------------------------------*/
k = find_good_place(n, xpts, ypts, r_sqr);
if (k != -1)
{
/*----------------------------------------------------------------------
/ Find the first point outside of the circle centered at 'pts[k]'
/---------------------------------------------------------------------*/
i = k;
do
{
if (--i < 0)
{
i = n - 2;
}
dx = xpts[i] - xpts[k];
dy = (ypts[i] - ypts[k]) * contour_vars.aspect_ratio;
dist = dx * dx + dy * dy;
}
while (dist < r_sqr);
/*----------------------------------------------------------------------
/ Find the intersection of line segment p[i]--p[i+1] with the circle
/---------------------------------------------------------------------*/
dx = xpts[i + 1] - xpts[i];
dy = (ypts[i + 1] - ypts[i]) * contour_vars.aspect_ratio;
ox = xpts[i] - xpts[k];
oy = (ypts[i] - ypts[k]) * contour_vars.aspect_ratio;
a = dx * dx + dy * dy;
b = ox * dx + oy * dy;
c = ox * ox + oy * oy - r_sqr;
t = -(b + sqrt(b * b - a * c)) / a;
xtpt1 = xpts[i] + t * dx;
ytpt1 = ypts[i] + t * (ypts[i + 1] - ypts[i]);
/*----------------------------------------------------------------------
/ Same as above but in the other direction
/---------------------------------------------------------------------*/
j = k;
do
{
if (++j >= n)
{
j = 1;
}
dx = xpts[j] - xpts[k];
dy = (ypts[j] - ypts[k]) * contour_vars.aspect_ratio;
dist = dx * dx + dy * dy;
}
while (dist < r_sqr);
/*----------------------------------------------------------------------
/ Find the intersection of line segment p[j]--p[j-1] with the circle
/---------------------------------------------------------------------*/
dx = xpts[j - 1] - xpts[j];
dy = (ypts[j - 1] - ypts[j]) * contour_vars.aspect_ratio;
ox = xpts[j] - xpts[k];
oy = (ypts[j] - ypts[k]) * contour_vars.aspect_ratio;
a = dx * dx + dy * dy;
b = ox * dx + oy * dy;
c = ox * ox + oy * oy - r_sqr;
t = -(b + sqrt(b * b - a * c)) / a;
xtpt2 = xpts[j] + t * dx;
ytpt2 = ypts[j] + t * (ypts[j - 1] - ypts[j]);
/*----------------------------------------------------------------------
/ Calculate the character up vector.
/---------------------------------------------------------------------*/
x_up_val = (ytpt1 - ytpt2) * contour_vars.aspect_ratio;
y_up_val = xtpt2 - xtpt1;
if (y_up_val < 0.0)
{
x_up_val = -x_up_val;
y_up_val = -y_up_val;
}
gks_set_text_upvec(x_up_val, y_up_val);
x_text_pos = (xpts[k] - contour_vars.wn[0]) * contour_vars.scale_factor
+ contour_vars.vp[0];
y_text_pos = (ypts[k] - contour_vars.wn[2]) * contour_vars.scale_factor
* contour_vars.aspect_ratio + contour_vars.vp[2];
gks_select_xform(contour_vars.ndc);
gks_text(x_text_pos, y_text_pos, label);
gks_select_xform(contour_vars.tnr);
/*---------------------------------------------------------------------/
/ Draw the contour line leaving a gap for the text.
/---------------------------------------------------------------------*/
if (i >= j)
{
xpts[i + 1] = xtpt1;
ypts[i + 1] = ytpt1;
xpts[j - 1] = xtpt2;
ypts[j - 1] = ytpt2;
/* zpts remain the same */
n_pts = i - j + 3;
gr_polyline3d(n_pts, xpts + j - 1, ypts + j - 1, zpts + j - 1);
}
else
{
xpts[i + 1] = xtpt1;
ypts[i + 1] = ytpt1;
n_pts = i + 2;
gr_polyline3d(n_pts, xpts, ypts, zpts);
xpts[j - 1] = xtpt2;
ypts[j - 1] = ytpt2;
n_pts = n - j + 1;
gr_polyline3d(n_pts, xpts + j - 1, ypts + j - 1, zpts + j - 1);
}
}
else
{
n_pts = n;
gr_polyline3d(n_pts, xpts, ypts, zpts);
}
}
static
void draw(double x, double y, double z, int iflag)
{
static int n = 0;
static double xpts[contour_max_pts];
static double ypts[contour_max_pts];
static double zpts[contour_max_pts];
static double line_length = 0;
static int z_exept_flag = 0;
double dx, dy;
int linetype;
char label[20];
switch (iflag % 10)
{
case 1: /* Continue polyline */
if (z_exept_flag == 0)
{
xpts[n] = x;
ypts[n] = y;
zpts[n] = z;
if ((contour_vars.txtflg == 1) &&
((contour_vars.lblmjh == 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1)))
{
dx = xpts[n] - xpts[n - 1];
dy = (ypts[n] - ypts[n - 1]) * contour_vars.aspect_ratio;
line_length += contour_vars.scale_factor *
sqrt(dx * dx + dy * dy);
}
n++;
if ((line_length >= contour_max_length) || (n >= contour_max_pts))
{
if ((contour_vars.txtflg == 1) &&
((contour_vars.lblmjh == 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1)))
{
linetype = GKS_K_LINETYPE_SOLID;
if (contour_vars.lblmjh > 1)
{
gks_set_pline_linetype(linetype);
}
sprintf(label, contour_vars.lblfmt, z);
label_line(n, xpts, ypts, zpts, label);
}
else
{
if ((contour_vars.lblmjh <= 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1))
{
linetype = GKS_K_LINETYPE_SOLID;
}
else
{
linetype = GKS_K_LINETYPE_DOTTED;
}
if (contour_vars.lblmjh > 1)
{
gks_set_pline_linetype(linetype);
}
gr_polyline3d(n, xpts, ypts, zpts);
}
xpts[0] = x;
ypts[0] = y;
zpts[0] = z;
line_length = 0.0;
n = 1;
}
}
break;
case 2: /* New polyline */
case 3:
if ((z > contour_vars.zmin) && (z < contour_vars.zmax))
{
z_exept_flag = 0;
xpts[0] = x;
ypts[0] = y;
zpts[0] = z;
line_length = 0.0;
n = 1;
}
else
z_exept_flag = 1;
break;
case 4: /* End polyline */
case 5:
if (z_exept_flag == 0)
{
xpts[n] = x;
ypts[n] = y;
zpts[n] = z;
if ((contour_vars.txtflg == 1) &&
((contour_vars.lblmjh == 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1)))
{
dx = xpts[n] - xpts[n - 1];
dy = (ypts[n] - ypts[n - 1]) * contour_vars.aspect_ratio;
line_length += contour_vars.scale_factor *
sqrt(dx * dx + dy * dy);
}
n++;
if ((line_length >= contour_min_length) &&
(contour_vars.txtflg == 1) &&
((contour_vars.lblmjh == 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1)))
{
linetype = GKS_K_LINETYPE_SOLID;
if (contour_vars.lblmjh > 1)
{
gks_set_pline_linetype(linetype);
}
sprintf(label, contour_vars.lblfmt, z);
label_line(n, xpts, ypts, zpts, label);
}
else
{
if ((contour_vars.lblmjh <= 1) ||
(((iflag / 10 - 1) % contour_vars.lblmjh) == 1))
{
linetype = GKS_K_LINETYPE_SOLID;
}
else
{
linetype = GKS_K_LINETYPE_DOTTED;
}
if (contour_vars.lblmjh > 1)
{
gks_set_pline_linetype(linetype);
}
gr_polyline3d(n, xpts, ypts, zpts);
}
}
break;
}
}
void FORTRAN(gr_polyline3d)(int *n, double *px, double *py, double *pz)
{
gr_polyline3d(*n, px, py, pz);
}
