/** updates point to the point on the arc at angle angle degrees */
void arc_get_point_at_angle(Arc *arc, Point* point, real angle)
{
Point vec;
vec.x = cos(angle/180.0*M_PI);
vec.y = -sin(angle/180.0*M_PI);
point_copy(point,&arc->center);
point_add_scaled(point,&vec,arc->radius);
}
void add_arrow_rectangle(Rectangle *rect,
const Point *vertex,
const Point *normed_dir,
double extra_long,double extra_trans)
{
Point vl,vt,pt;
vl = *normed_dir;
point_get_perp(&vt,&vl);
point_copy_add_scaled(&pt,vertex,&vl,extra_long);
point_add_scaled(&pt,&vt,extra_trans);
rectangle_add_point(rect,&pt);
point_add_scaled(&pt,&vt,-2.0 * extra_trans);
rectangle_add_point(rect,&pt);
point_add_scaled(&pt,&vl,-2.0 * extra_long);
rectangle_add_point(rect,&pt);
point_add_scaled(&pt,&vt,2.0 * extra_trans);
rectangle_add_point(rect,&pt);
}
void
point_convex(Point *dst, const Point *src1, const Point *src2, real alpha)
{
/* Make convex combination of src1 and src2:
dst = alpha * src1 + (1-alpha) * src2;
*/
point_copy(dst,src1);
point_scale(dst,alpha);
point_add_scaled(dst,src2,1.0 - alpha);
}
void
polyline_calculate_gap_endpoints(Polyline *polyline, Point *gap_endpoints)
{
Point start_vec, end_vec;
ConnectionPoint *start_cp, *end_cp;
int n = polyline->poly.numpoints;
gap_endpoints[0] = polyline->poly.points[0];
gap_endpoints[1] = polyline->poly.points[n-1];
start_cp = (polyline->poly.object.handles[0])->connected_to;
end_cp = (polyline->poly.object.handles[polyline->poly.object.num_handles-1])->connected_to;
if (connpoint_is_autogap(start_cp)) {
gap_endpoints[0] = calculate_object_edge(&gap_endpoints[0],
&polyline->poly.points[1],
start_cp->object);
}
if (connpoint_is_autogap(end_cp)) {
gap_endpoints[1] = calculate_object_edge(&gap_endpoints[1],
&polyline->poly.points[n-2],
end_cp->object);
}
start_vec = gap_endpoints[0];
point_sub(&start_vec, &polyline->poly.points[0]);
point_normalize(&start_vec);
end_vec = gap_endpoints[1];
point_sub(&end_vec, &polyline->poly.points[n-1]);
point_normalize(&end_vec);
/* add absolute gap */
point_add_scaled(&gap_endpoints[0], &start_vec, polyline->absolute_start_gap);
point_add_scaled(&gap_endpoints[1], &end_vec, polyline->absolute_end_gap);
}
/*!
* \brief Set the other point of the pattern
*
* The meaning of the point depends on the type of the pattern.
* For line gradient it is the second point giving the direction.
* With a radial gradient it is the focal point.
*
* \ingroup DiaPattern
*/
void
dia_pattern_set_point (DiaPattern *self, real x, real y)
{
self->other.x = x;
self->other.y = y;
/* with radial we have to ensure the point is in circle */
if (self->type == DIA_RADIAL_GRADIENT) {
real dist = distance_ellipse_point (&self->start, self->radius*2, self->radius*2, 0.0, &self->other);
if (dist > 0) {
/* If the point defined by ‘fx’ and ‘fy’ lies outside the circle defined
* by ‘cx’, ‘cy’ and ‘r’, then the user agent shall set the focal point to
* the intersection of the line from (‘cx’, ‘cy’) to (‘fx’, ‘fy’) with the
* circle defined by ‘cx’, ‘cy’ and ‘r’
*/
Point p1 = self->start;
Point p2 = self->other;
point_sub (&p2, &p1);
point_normalize (&p2);
point_add_scaled (&p1, &p2, self->radius);
self->other = p1;
}
}
}
static void
compute_gap_points(Bezierline *bezierline, Point *gap_points)
{
real bez_length;
BezierConn *bez = &bezierline->bez;
Point vec_start, vec_end;
gap_points[0] = bez->bezier.points[0].p1;
gap_points[1] = bez->bezier.points[1].p1;
gap_points[2] = bez->bezier.points[bez->bezier.num_points-1].p2;
gap_points[3] = bez->bezier.points[bez->bezier.num_points-1].p3;
point_copy(&vec_start, &gap_points[1]);
point_sub(&vec_start, &gap_points[0]);
point_normalize(&vec_start); /* unit vector pointing from first point */
point_copy(&vec_end, &gap_points[2]);
point_sub(&vec_end, &gap_points[3]);
point_normalize(&vec_end); /* unit vector pointing from last point */
bez_length = approx_bez_length(bez) ;
if (connpoint_is_autogap(bez->object.handles[0]->connected_to) &&
(bez->object.handles[0])->connected_to != NULL &&
(bez->object.handles[0])->connected_to->object != NULL ) {
Point end;
point_copy(&end, &gap_points[0]);
point_add_scaled(&end, &vec_start, bez_length); /* far away on the same slope */
end = calculate_object_edge(&gap_points[0], &end,
(bez->object.handles[0])->connected_to->object);
point_sub(&end, &gap_points[0]); /* vector from old start to new start */
/* move points */
point_add(&gap_points[0], &end);
point_add(&gap_points[1], &end);
}
if (connpoint_is_autogap(bez->object.handles[3*(bez->bezier.num_points-1)]->connected_to) &&
(bez->object.handles[3*(bez->bezier.num_points-1)])->connected_to != NULL &&
(bez->object.handles[3*(bez->bezier.num_points-1)])->connected_to->object != NULL) {
Point end;
point_copy(&end, &gap_points[3]);
point_add_scaled(&end, &vec_end, bez_length); /* far away on the same slope */
end = calculate_object_edge(&gap_points[3], &end,
(bez->object.handles[3*(bez->bezier.num_points-1)])->connected_to->object);
point_sub(&end, &gap_points[3]); /* vector from old end to new end */
/* move points */
point_add(&gap_points[3], &end);
point_add(&gap_points[2], &end);
}
/* adds the absolute start gap according to the slope at the first point */
point_add_scaled(&gap_points[0], &vec_start, bezierline->absolute_start_gap);
point_add_scaled(&gap_points[1], &vec_start, bezierline->absolute_start_gap);
/* adds the absolute end gap according to the slope at the last point */
point_add_scaled(&gap_points[2], &vec_end, bezierline->absolute_end_gap);
point_add_scaled(&gap_points[3], &vec_end, bezierline->absolute_end_gap);
}
