object-snapper.cpp revision 6fc0952fcafd54a656fdc8257ebb44bad58af163
/**
* \file object-snapper.cpp
* \brief Snapping things to objects.
*
* Authors:
* Carl Hetherington <inkscape@carlh.net>
* Diederik van Lierop <mail@diedenrezi.nl>
*
* Copyright (C) 2005 - 2008 Authors
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include "libnr/n-art-bpath.h"
#include "libnr/nr-rect-ops.h"
#include "libnr/nr-point-fns.h"
#include "libnr/n-art-bpath-2geom.h"
#include "document.h"
#include "sp-namedview.h"
#include "sp-image.h"
#include "sp-item-group.h"
#include "sp-item.h"
#include "sp-use.h"
#include "desktop.h"
#include "inkscape.h"
#include "prefs-utils.h"
#include "sp-text.h"
#include "sp-flowtext.h"
#include "text-editing.h"
#include "sp-clippath.h"
#include "sp-mask.h"
Inkscape::SnapCandidate::SnapCandidate(SPItem* item, bool clip_or_mask, NR::Matrix additional_affine)
{
}
{
}
_strict_snapping(true), _include_item_center(false)
{
}
{
_candidates->clear();
delete _candidates;
delete _points_to_snap_to;
_clear_paths();
delete _paths_to_snap_to;
delete _bpaths_to_snap_to;
}
/**
* Find all items within snapping range.
* \param parent Pointer to the document's root, or to a clipped path or mask object
* \param it List of items to ignore
* \param first_point If true then this point is the first one from a whole bunch of points
* \param bbox_to_snap Bounding box hulling the whole bunch of points, all from the same selection and having the same transformation
* \param DimensionToSnap Snap in X, Y, or both directions.
*/
bool const &first_point,
DimensionToSnap const snap_dim,
bool const clip_or_mask,
{
return;
}
if (first_point) {
_candidates->clear();
}
if (SP_IS_ITEM(o) && !SP_ITEM(o)->isLocked() && !(desktop->itemIsHidden(SP_ITEM(o)) && !clip_or_mask)) {
// Don't snap to locked items, and
// don't snap to hidden objects, unless they're a clipped path or a mask
/* See if this item is on the ignore list */
i++;
}
}
if (item) {
if (clip_or_mask) { // If the current item is a clipping path or a mask
// then store the transformation of the clipped path or mask itself
// but also take into account the additional affine of the object
// being clipped / masked
} else { // cannot clip or mask more than once
// The current item is not a clipping path or a mask, but might
// still be the subject of clipping or masking itself ; if so, then
// we should also consider that path or mask for snapping to
if (obj) {
}
if (obj) {
}
}
}
if (SP_IS_GROUP(o)) {
} else {
if (clip_or_mask) {
// Oh oh, this will get ugly. We cannot use sp_item_i2d_affine directly because we need to
// insert an additional transformation in document coordinates (code copied from sp_item_i2d_affine)
true);
} else {
}
// See if the item is within range
if (bbox_of_item) {
// This item is within snapping range, so record it as a candidate
}
}
}
}
}
}
}
bool const &first_point) const
{
// Now, let's first collect all points to snap to. If we have a whole bunch of points to snap,
// e.g. when translating an item using the selector tool, then we will only do this for the
// first point and store the collection for later use. This significantly improves the performance
if (first_point) {
// Determine the type of bounding box we should snap to
// A point considered for snapping should be either a node, a bbox corner or a guide. Pick only ONE!
g_assert(!(p_is_a_node && p_is_a_bbox || p_is_a_bbox && p_is_a_guide || p_is_a_node && p_is_a_guide));
if (_snap_to_bboxnode) {
bbox_type = (prefs_bbox == 0)?
}
for (std::vector<SnapCandidate>::const_iterator i = _candidates->begin(); i != _candidates->end(); i++) {
//NR::Matrix i2doc(NR::identity());
}
//Collect all nodes so we can snap to them
if (_snap_to_itemnode) {
}
}
//Collect the bounding box's corners so we can snap to them
if (_snap_to_bboxnode) {
// Discard the bbox of a clipped path / mask, because we don't want to snap to both the bbox
// of the item AND the bbox of the clipping path at the same time
if (!(*i).clip_or_mask) {
if (b) {
for ( unsigned k = 0 ; k < 4 ; k++ ) {
}
}
}
}
}
}
}
}
bool const &first_point,
{
// Iterate through all nodes, find out which one is the closest to p, and snap to it!
_collectNodes(t, first_point);
if (unselected_nodes != NULL) {
_points_to_snap_to->insert(_points_to_snap_to->end(), unselected_nodes->begin(), unselected_nodes->end());
}
SnappedPoint s;
bool success = false;
for (std::vector<NR::Point>::const_iterator k = _points_to_snap_to->begin(); k != _points_to_snap_to->end(); k++) {
success = true;
}
}
if (success) {
}
}
{
// Iterate through all nodes, find out which one is the closest to this guide, and snap to it!
_collectNodes(t, true);
SnappedPoint s;
bool success = false;
for (std::vector<NR::Point>::const_iterator k = _points_to_snap_to->begin(); k != _points_to_snap_to->end(); k++) {
// Project each node (*k) on the guide line (running through point p)
NR::Coord dist2 = NR::L2(p - p_proj); // distance from projection of node on the guide, to the mouse location
success = true;
}
}
if (success) {
}
}
/**
* Returns index of first NR_END bpath in array.
*/
{
unsigned ret = 0;
++ret;
}
++ret;
return ret;
}
bool const &first_point,
NArtBpath const *border_bpath) const
{
// Now, let's first collect all paths to snap to. If we have a whole bunch of points to snap,
// e.g. when translating an item using the selector tool, then we will only do this for the
// first point and store the collection for later use. This significantly improves the performance
if (first_point) {
_clear_paths();
// Determine the type of bounding box we should snap to
if (_snap_to_bboxpath) {
bbox_type = (prefs_bbox ==0)?
}
// Consider the page border for snapping
if (border_bpath != NULL) {
// make our own copy of the const*
}
for (std::vector<SnapCandidate>::const_iterator i = _candidates->begin(); i != _candidates->end(); i++) {
/* Transform the requested snap point to this item's coordinates */
/* We might have a clone at hand, so make sure we get the root item */
} else {
}
//Build a list of all paths considered for snapping to
//Add the item's path to snap to
if (_snap_to_itempath) {
if (!(_strict_snapping && !p_is_a_node)) {
// Snapping to the path of characters is very cool, but for a large
// chunk of text this will take ages! So limit snapping to text paths
// containing max. 240 characters. Snapping the bbox will not be affected
bool very_lenghty_prose = false;
}
// On my AMD 3000+, the snapping lag becomes annoying at approx. 240 chars
// which corresponds to a lag of 500 msec. This is for snapping a rect
// to a single line of text.
// Snapping for example to a traced bitmap is also very stressing for
// the CPU, so we'll only snap to paths having no more than 500 nodes
// This also leads to a lag of approx. 500 msec (in my lousy test set-up).
bool very_complex_path = false;
if (SP_IS_PATH(root_item)) {
}
if (!very_lenghty_prose && !very_complex_path) {
if (curve) {
(*i).additional_affine);
// Perhaps for speed, get a reference to the Geom::pathvector, and store the transformation besides it.
_bpaths_to_snap_to->push_back(bpath); // we will get a dupe of the path, which must be freed at some point
/*std::vector<Geom::Path> pathv;
char *svgpath = sp_svg_write_path(bpath);
if (svgpath) {
std::cout << "path = " << svgpath << std::endl;
}
g_free(svgpath);
*/
}
}
}
}
//Add the item's bounding box to snap to
if (_snap_to_bboxpath) {
if (!(_strict_snapping && p_is_a_node)) {
// Discard the bbox of a clipped path / mask, because we don't want to snap to both the bbox
// of the item AND the bbox of the clipping path at the same time
if (!(*i).clip_or_mask) {
}
}
}
}
}
}
bool const &first_point,
SPPath const *selected_path,
NArtBpath const *border_bpath) const
{
// Now we can finally do the real snapping, using the paths collected above
SnappedPoint s;
bool success = false;
/* FIXME: this seems like a hack. Perhaps Snappers should be
** in SPDesktop rather than SPNamedView?
*/
if (first_point) {
/* While editing a path in the node tool, findCandidates must ignore that path because
* of the node snapping requirements (i.e. only unselected nodes must be snapable).
* This path must not be ignored however when snapping to the paths, so we add it here
* manually when applicable.
*
* Note that this path must be the last in line!
* */
if (node_tool_active) {
if (curve) {
NArtBpath *bpath = bpath_for_curve(SP_ITEM(selected_path), curve, true, true, NR::identity(), NR::identity());
_bpaths_to_snap_to->push_back(bpath); // we will get a dupe of the path, which must be freed at some point
}
}
// Convert all bpaths to Paths, because here we really must have Paths
// (whereas in _snapPathsConstrained we will use the original bpaths)
for (std::vector<NArtBpath*>::const_iterator k = _bpaths_to_snap_to->begin(); k != _bpaths_to_snap_to->end(); k++) {
if (path) {
}
}
}
for (std::vector<Path*>::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); k++) {
if (*k) {
//if true then this path k is currently being edited in the node tool
//pts describes a polyline approximation, which might consist of 1000s of points!
if (being_edited) {
/* If the path is being edited, then we will try to snap to each piece of the
* path individually. We should only snap though to stationary pieces of the paths
* and not to the pieces that are being dragged around. This way we avoid
* self-snapping. For this we check whether the nodes at both ends of the current
* piece are unselected; if they are then this piece must be stationary
*/
// Example: a cubic spline is a single piece within a path; it will be drawn using
// a polyline, which is described by the collection of lines between the points pts[i]
o = get_nearest_position_on_Path(*k, p_doc, i);
}
} else {
/* If the path is NOT being edited, then we will try to snap to the path as a
* whole, so we need to do this only once and we will break out at the end of
* this for-loop iteration */
/* Look for the nearest position on this SPItem to our snap point */
o = get_nearest_position_on_Path(*k, p_doc);
}
if (o && o->t >= 0 && o->t <= 1) {
/* Convert the nearest point back to desktop coordinates */
/* IF YOU'RE BUG HUNTING: IT LOOKS LIKE get_point_on_Path SOMETIMES
* RETURNS THE WRONG POINT (WITH AN OFFSET, BUT STILL ON THE PATH.
* THIS BUG WILL NO LONGER BE ENCOUNTERED ONCE WE'VE SWITCHED TO
* 2GEOM FOR THE OBJECT SNAPPER
*/
if (dist < getSnapperTolerance()) {
// if we snap to a straight line segment (within a path), then return this line segment
if ((*k)->IsLineSegment(o->piece)) {
sc.lines.push_back(Inkscape::SnappedLineSegment(o_dt, dist, getSnapperTolerance(), getSnapperAlwaysSnap(), start_point, end_point));
} else {
// for segments other than straight lines of a path, we'll return just the closest snapped point
if (dist < s.getDistance()) {
success = true;
}
}
}
}
// If the path is NOT being edited, then we will try to snap to the path as a whole
// so we need to do this only once
if (!being_edited) break;
}
}
}
if (success) {
}
}
/* Returns true if point is coincident with one of the unselected nodes */
bool Inkscape::ObjectSnapper::isUnselectedNode(NR::Point const &point, std::vector<NR::Point> const *unselected_nodes) const
{
if (unselected_nodes == NULL) {
return false;
}
if (unselected_nodes->size() == 0) {
return false;
}
for (std::vector<NR::Point>::const_iterator i = unselected_nodes->begin(); i != unselected_nodes->end(); i++) {
return true;
}
}
return false;
}
bool const &first_point,
ConstraintLine const &c) const
{
// Consider the page's border for snapping to
// Now we can finally do the real snapping, using the paths collected above
/* FIXME: this seems like a hack. Perhaps Snappers should be
** in SPDesktop rather than SPNamedView?
*/
if (!is_zero(direction_vector)) {
}
// The intersection point of the constraint line with any path,
// must lie within two points on the constraintline: p_min_on_cl and p_max_on_cl
// The distance between those points is twice the snapping tolerance
NR::Point const p_min_on_cl = desktop->dt2doc(p_proj_on_cl - getSnapperTolerance() * direction_vector);
NR::Point const p_max_on_cl = desktop->dt2doc(p_proj_on_cl + getSnapperTolerance() * direction_vector);
for (std::vector<NArtBpath*>::const_iterator k = _bpaths_to_snap_to->begin(); k != _bpaths_to_snap_to->end(); k++) {
if (*k) {
// TODO: (Diederik) Only do this once for the first point, needs some storage of pointers in a member variable
// We need only the first element of cs, because cl is only a single straight linesegment
// This first element contains a vector filled with crossings of cl with path_2geom
// Reconstruct the point of intersection
// When it's within snapping range, then return it
// (within snapping range == between p_min_on_cl and p_max_on_cl == 0 < ta < 1)
SnappedPoint s(desktop->doc2dt(p_inters), SNAPTARGET_PATH, dist, getSnapperTolerance(), getSnapperAlwaysSnap());
}
}
}
}
}
}
bool const &first_point,
{
return;
}
/* Get a list of all the SPItems that we will try to snap to */
if (first_point) {
_findCandidates(sp_document_root(_named_view->document), it, first_point, local_bbox_to_snap, TRANSL_SNAP_XY, false, NR::identity());
}
if (_snap_to_itemnode || _snap_to_bboxnode) {
}
// Consider the page's border for snapping to
if (n > 0) {
/* While editing a path in the node tool, findCandidates must ignore that path because
* of the node snapping requirements (i.e. only unselected nodes must be snapable).
* That path must not be ignored however when snapping to the paths, so we add it here
* manually when applicable
*/
}
} else {
}
}
}
bool const &first_point,
ConstraintLine const &c,
{
return;
}
/* Get a list of all the SPItems that we will try to snap to */
if (first_point) {
_findCandidates(sp_document_root(_named_view->document), it, first_point, local_bbox_to_snap, TRANSL_SNAP_XY, false, NR::identity());
}
// A constrained snap, is a snap in only one degree of freedom (specified by the constraint line).
// This is usefull for example when scaling an object while maintaining a fixed aspect ratio. It's
// nodes are only allowed to move in one direction (i.e. in one degree of freedom).
// When snapping to objects, we either snap to their nodes or their paths. It is however very
// unlikely that any node will be exactly at the constrained line, so for a constrained snap
// to objects we will only consider the object's paths. Beside, the nodes will be at these paths,
// so we will more or less snap to them anyhow.
}
}
// This method is used to snap a guide to nodes, while dragging the guide around
{
if ( NULL == _named_view ) {
return;
}
/* Get a list of all the SPItems that we will try to snap to */
} else {
}
// We don't support ANGLED_GUIDE_ROT_SNAP yet.
// It would be cool to allow the user to rotate a guide by dragging it, instead of
// only translating it. (For example when CTRL is pressed). We will need an UI part
// for that first; and some important usability choices need to be made:
// E.g. which point should be used for pivoting? A previously snapped point,
// or a transformation center (which can be moved after clicking for the
// second time on an object; but should this point then be constrained to the
// line, or can it be located anywhere?)
_findCandidates(sp_document_root(_named_view->document), &it, true, NR::Rect(p, p), snap_dim, false, NR::identity());
// _snapRotatingGuideToNodes has not been implemented yet.
}
/**
* \return true if this Snapper will snap at least one kind of point.
*/
{
bool snap_to_something = _snap_to_itempath || _snap_to_itemnode || _snap_to_bboxpath || _snap_to_bboxnode || _snap_to_page_border;
}
{
}
{
for (std::vector<NArtBpath*>::const_iterator k = _bpaths_to_snap_to->begin(); k != _bpaths_to_snap_to->end(); k++) {
g_free(*k);
}
for (std::vector<Path*>::const_iterator k = _paths_to_snap_to->begin(); k != _paths_to_snap_to->end(); k++) {
delete *k;
}
}
{
Geom::Rect const border_rect = Geom::Rect(Geom::Point(0,0), Geom::Point(sp_document_width(_named_view->document),sp_document_height(_named_view->document)));
if (border_curve) {
}
return border_bpath;
}
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4 :