ObjectChange *
beziershape_move_handle(BezierShape *bezier, Handle *handle,
Point *to, ConnectionPoint *cp,
HandleMoveReason reason, ModifierKeys modifiers)
{
int handle_nr, comp_nr, next_nr, prev_nr;
Point delta, pt;
delta = *to;
point_sub(&delta, &handle->pos);
handle_nr = get_handle_nr(bezier, handle);
comp_nr = get_comp_nr(handle_nr);
next_nr = comp_nr + 1;
prev_nr = comp_nr - 1;
if (comp_nr == bezier->numpoints - 1)
next_nr = 1;
if (comp_nr == 1)
prev_nr = bezier->numpoints - 1;
switch(handle->id) {
case HANDLE_BEZMAJOR:
if (comp_nr == bezier->numpoints - 1) {
bezier->points[comp_nr].p3 = *to;
bezier->points[0].p1 = bezier->points[0].p3 = *to;
point_add(&bezier->points[comp_nr].p2, &delta);
point_add(&bezier->points[1].p1, &delta);
} else {
bezier->points[comp_nr].p3 = *to;
point_add(&bezier->points[comp_nr].p2, &delta);
point_add(&bezier->points[comp_nr+1].p1, &delta);
}
break;
case HANDLE_LEFTCTRL:
bezier->points[comp_nr].p2 = *to;
switch (bezier->corner_types[comp_nr]) {
case BEZ_CORNER_SYMMETRIC:
pt = bezier->points[comp_nr].p3;
point_sub(&pt, &bezier->points[comp_nr].p2);
point_add(&pt, &bezier->points[comp_nr].p3);
bezier->points[next_nr].p1 = pt;
break;
case BEZ_CORNER_SMOOTH: {
real len;
pt = bezier->points[next_nr].p1;
point_sub(&pt, &bezier->points[comp_nr].p3);
len = point_len(&pt);
pt = bezier->points[comp_nr].p3;
point_sub(&pt, &bezier->points[comp_nr].p2);
if (point_len(&pt) > 0)
point_normalize(&pt);
else {
pt.x = 1.0; pt.y = 0.0;
}
point_scale(&pt, len);
point_add(&pt, &bezier->points[comp_nr].p3);
bezier->points[next_nr].p1 = pt;
break;
}
case BEZ_CORNER_CUSP:
/* no mirror point movement required */
break;
}
break;
case HANDLE_RIGHTCTRL:
bezier->points[comp_nr].p1 = *to;
switch (bezier->corner_types[prev_nr]) {
case BEZ_CORNER_SYMMETRIC:
pt = bezier->points[prev_nr].p3;
point_sub(&pt, &bezier->points[comp_nr].p1);
point_add(&pt, &bezier->points[prev_nr].p3);
bezier->points[prev_nr].p2 = pt;
break;
case BEZ_CORNER_SMOOTH: {
real len;
pt = bezier->points[prev_nr].p2;
point_sub(&pt, &bezier->points[prev_nr].p3);
len = point_len(&pt);
pt = bezier->points[prev_nr].p3;
point_sub(&pt, &bezier->points[comp_nr].p1);
if (point_len(&pt) > 0)
point_normalize(&pt);
else {
pt.x = 1.0; pt.y = 0.0;
}
point_scale(&pt, len);
point_add(&pt, &bezier->points[prev_nr].p3);
bezier->points[prev_nr].p2 = pt;
break;
}
case BEZ_CORNER_CUSP:
/* no mirror point movement required */
break;
}
break;
default:
message_error("Internal error in beziershape_move_handle.");
break;
}
return NULL;
}
/*!
* \brief Move one of the handles associated with the
* @param bezier The object whose handle is being moved.
* @param handle The handle being moved.
* @param to The position it has been moved to (corrected for
* vertical/horizontal only movement).
* @param cp If non-NULL, the connectionpoint found at this position.
* If @a cp is NULL, there may or may not be a connectionpoint.
* @param reason ignored
* @param modifiers ignored
* @return NULL
* \memberof BezierConn
*/
ObjectChange*
bezierconn_move_handle (BezierConn *bezier,
Handle *handle,
Point *to,
ConnectionPoint *cp,
HandleMoveReason reason,
ModifierKeys modifiers)
{
int handle_nr, comp_nr;
Point delta, pt;
delta = *to;
point_sub(&delta, &handle->pos);
handle_nr = get_handle_nr(bezier, handle);
comp_nr = get_comp_nr(handle_nr);
switch(handle->id) {
case HANDLE_MOVE_STARTPOINT:
bezier->bezier.points[0].p1 = *to;
/* shift adjacent point */
point_add(&bezier->bezier.points[1].p1, &delta);
break;
case HANDLE_MOVE_ENDPOINT:
bezier->bezier.points[bezier->bezier.num_points-1].p3 = *to;
/* shift adjacent point */
point_add(&bezier->bezier.points[bezier->bezier.num_points-1].p2, &delta);
break;
case HANDLE_BEZMAJOR:
bezier->bezier.points[comp_nr].p3 = *to;
/* shift adjacent point */
point_add(&bezier->bezier.points[comp_nr].p2, &delta);
point_add(&bezier->bezier.points[comp_nr+1].p1, &delta);
break;
case HANDLE_LEFTCTRL:
bezier->bezier.points[comp_nr].p2 = *to;
if (comp_nr < bezier->bezier.num_points - 1) {
switch (bezier->bezier.corner_types[comp_nr]) {
case BEZ_CORNER_SYMMETRIC:
pt = bezier->bezier.points[comp_nr].p3;
point_sub(&pt, &bezier->bezier.points[comp_nr].p2);
point_add(&pt, &bezier->bezier.points[comp_nr].p3);
bezier->bezier.points[comp_nr+1].p1 = pt;
break;
case BEZ_CORNER_SMOOTH: {
real len;
pt = bezier->bezier.points[comp_nr+1].p1;
point_sub(&pt, &bezier->bezier.points[comp_nr].p3);
len = point_len(&pt);
pt = bezier->bezier.points[comp_nr].p2;
point_sub(&pt, &bezier->bezier.points[comp_nr].p3);
if (point_len(&pt) > 0)
point_normalize(&pt);
else { pt.x = 1.0; pt.y = 0.0; }
point_scale(&pt, -len);
point_add(&pt, &bezier->bezier.points[comp_nr].p3);
bezier->bezier.points[comp_nr+1].p1 = pt;
break;
}
case BEZ_CORNER_CUSP:
/* Do nothing to the other guy */
break;
}
}
break;
case HANDLE_RIGHTCTRL:
bezier->bezier.points[comp_nr].p1 = *to;
if (comp_nr > 1) {
switch (bezier->bezier.corner_types[comp_nr-1]) {
case BEZ_CORNER_SYMMETRIC:
pt = bezier->bezier.points[comp_nr - 1].p3;
point_sub(&pt, &bezier->bezier.points[comp_nr].p1);
point_add(&pt, &bezier->bezier.points[comp_nr - 1].p3);
bezier->bezier.points[comp_nr-1].p2 = pt;
break;
case BEZ_CORNER_SMOOTH: {
real len;
pt = bezier->bezier.points[comp_nr-1].p2;
point_sub(&pt, &bezier->bezier.points[comp_nr-1].p3);
len = point_len(&pt);
pt = bezier->bezier.points[comp_nr].p1;
point_sub(&pt, &bezier->bezier.points[comp_nr-1].p3);
if (point_len(&pt) > 0)
point_normalize(&pt);
else { pt.x = 1.0; pt.y = 0.0; }
point_scale(&pt, -len);
point_add(&pt, &bezier->bezier.points[comp_nr-1].p3);
bezier->bezier.points[comp_nr-1].p2 = pt;
break;
}
case BEZ_CORNER_CUSP:
/* Do nothing to the other guy */
break;
}
}
break;
default:
g_warning("Internal error in bezierconn_move_handle.\n");
break;
}
return NULL;
}
