1 files changed, 311 insertions, 0 deletions
diff --git a/src/object/sp-conn-end.cpp b/src/object/sp-conn-end.cpp
new file mode 100644
index 0000000..a419ae1
--- /dev/null
+++ b/src/object/sp-conn-end.cpp
@@ -0,0 +1,311 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/** @file
+ * TODO: insert short description here
+ *//*
+ * Authors: see git history
+ *
+ * Copyright (C) 2018 Authors
+ * Released under GNU GPL v2+, read the file 'COPYING' for more information.
+ */
+#include "sp-conn-end.h"
+
+#include <cstring>
+#include <string>
+#include <limits>
+
+#include "bad-uri-exception.h"
+#include "display/curve.h"
+#include "xml/repr.h"
+#include "sp-path.h"
+#include "uri.h"
+#include "document.h"
+#include "sp-item-group.h"
+#include "2geom/path-intersection.h"
+
+
+static void change_endpts(SPCurve *const curve, double const endPos[2]);
+
+SPConnEnd::SPConnEnd(SPObject *const owner)
+    : ref(owner)
+    , sub_ref(owner)
+    , href(nullptr)
+    , sub_href(nullptr)
+    // Default to center connection endpoint
+    , _changed_connection()
+    , _delete_connection()
+    , _transformed_connection()
+    , _group_connection()
+{
+}
+
+static SPObject const *get_nearest_common_ancestor(SPObject const *const obj, SPItem const *const objs[2])
+{
+    SPObject const *anc_sofar = obj;
+    for (unsigned i = 0; i < 2; ++i) {
+        if ( objs[i] != nullptr ) {
+            anc_sofar = anc_sofar->nearestCommonAncestor(objs[i]);
+        }
+    }
+    return anc_sofar;
+}
+
+
+static bool try_get_intersect_point_with_item_recursive(Geom::PathVector& conn_pv, SPItem* item,
+        const Geom::Affine& item_transform, double& intersect_pos)
+{
+    double initial_pos = intersect_pos;
+    // if this is a group...
+    if (SP_IS_GROUP(item)) {
+        SPGroup* group = SP_GROUP(item);
+
+        // consider all first-order children
+        double child_pos = 0.0;
+        std::vector<SPItem*> g = sp_item_group_item_list(group);
+        for (auto child_item : g) {
+            try_get_intersect_point_with_item_recursive(conn_pv, child_item,
+                    item_transform * child_item->transform, child_pos);
+            if (intersect_pos < child_pos)
+                intersect_pos = child_pos;
+        }
+        return intersect_pos != initial_pos;
+    }
+
+    // if this is not a shape, nothing to be done
+    auto shape = dynamic_cast<SPShape const *>(item);
+    if (!shape)
+        return false;
+
+    // make sure it has an associated curve
+    auto item_curve = SPCurve::copy(shape->curve());
+    if (!item_curve) return false;
+
+    // apply transformations (up to common ancestor)
+    item_curve->transform(item_transform);
+
+    const Geom::PathVector& curve_pv = item_curve->get_pathvector();
+    Geom::CrossingSet cross = crossings(conn_pv, curve_pv);
+    // iterate over all Crossings
+    //TODO: check correctness of the following code: inner loop uses loop variable
+    //      with a name identical to the loop variable of the outer loop. Then rename.
+    for (const auto & cr : cross) {
+        for (const auto & cr_pt : cr) {
+            if ( intersect_pos < cr_pt.ta)
+                intersect_pos = cr_pt.ta;
+        }
+    }
+
+    return intersect_pos != initial_pos;
+}
+
+
+// This function returns the outermost intersection point between the path (a connector)
+// and the item given.  If the item is a group, then the component items are considered.
+// The transforms given should be to a common ancestor of both the path and item.
+//
+static bool try_get_intersect_point_with_item(SPPath* conn, SPItem* item,
+        const Geom::Affine& item_transform, const Geom::Affine& conn_transform,
+        const bool at_start, double& intersect_pos)
+{
+    // Copy the curve and apply transformations up to common ancestor.
+    auto conn_curve = conn->curve()->copy();
+    conn_curve->transform(conn_transform);
+
+    Geom::PathVector conn_pv = conn_curve->get_pathvector();
+
+    // If this is not the starting point, use Geom::Path::reverse() to reverse the path
+    if (!at_start) {
+        // connectors are actually a single path, so consider the first element from a Geom::PathVector
+        conn_pv[0] = conn_pv[0].reversed();
+    }
+
+    // We start with the intersection point at the beginning of the path
+    intersect_pos = 0.0;
+
+    // Find the intersection.
+    bool result = try_get_intersect_point_with_item_recursive(conn_pv, item, item_transform, intersect_pos);
+
+    if (!result) {
+        // No intersection point has been found (why?)
+        // just default to connector end
+        intersect_pos = 0;
+    }
+    // If not at the starting point, recompute position with respect to original path
+    if (!at_start) {
+        intersect_pos = conn_pv[0].size() - intersect_pos;
+    }
+
+    return result;
+}
+
+
+static void sp_conn_get_route_and_redraw(SPPath *const path, const bool updatePathRepr = true)
+{
+    // Get the new route around obstacles.
+    bool rerouted = path->connEndPair.reroutePathFromLibavoid();
+    if (!rerouted) {
+        return;
+    }
+
+    SPItem *h2attItem[2] = {nullptr};
+    path->connEndPair.getAttachedItems(h2attItem);
+
+    SPObject const *const ancestor = get_nearest_common_ancestor(path, h2attItem);
+    Geom::Affine const path2anc(i2anc_affine(path, ancestor));
+
+    // Set sensible values in case there the connector ends are not
+    // attached to any shapes.
+    Geom::PathVector conn_pv = path->curve()->get_pathvector();
+    double endPos[2] = { 0.0, static_cast<double>(conn_pv[0].size()) };
+
+    for (unsigned h = 0; h < 2; ++h) {
+        // Assume center point for all
+        if (h2attItem[h]) {
+            Geom::Affine h2i2anc = i2anc_affine(h2attItem[h], ancestor);
+            try_get_intersect_point_with_item(path, h2attItem[h], h2i2anc, path2anc,
+                        (h == 0), endPos[h]);
+        }
+    }
+    change_endpts(path->curve(), endPos);
+    if (updatePathRepr) {
+        path->updateRepr();
+        path->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+    }
+}
+
+
+static void sp_conn_end_shape_modified(SPObject */*moved_item*/, int /*flags*/, SPPath *const path)
+{
+    if (path->connEndPair.isAutoRoutingConn()) {
+        path->connEndPair.tellLibavoidNewEndpoints();
+    }
+}
+
+
+void sp_conn_reroute_path(SPPath *const path)
+{
+    if (path->connEndPair.isAutoRoutingConn()) {
+        path->connEndPair.tellLibavoidNewEndpoints();
+    }
+}
+
+
+void sp_conn_reroute_path_immediate(SPPath *const path)
+{
+    if (path->connEndPair.isAutoRoutingConn()) {
+        bool processTransaction = true;
+        path->connEndPair.tellLibavoidNewEndpoints(processTransaction);
+    }
+    // Don't update the path repr or else connector dragging is slowed by
+    // constant update of values to the xml editor, and each step is also
+    // needlessly remembered by undo/redo.
+    bool const updatePathRepr = false;
+    sp_conn_get_route_and_redraw(path, updatePathRepr);
+}
+
+void sp_conn_redraw_path(SPPath *const path)
+{
+    sp_conn_get_route_and_redraw(path);
+}
+
+
+static void change_endpts(SPCurve *const curve, double const endPos[2])
+{
+    // Use Geom::Path::portion to cut the curve at the end positions
+    if (endPos[0] > endPos[1]) {
+        // Path is "negative", reset the curve and return
+        curve->reset();
+        return;
+    }
+    const Geom::Path& old_path = curve->get_pathvector()[0];
+    Geom::PathVector new_path_vector;
+    new_path_vector.push_back(old_path.portion(endPos[0], endPos[1]));
+    curve->set_pathvector(new_path_vector);
+}
+
+static void sp_conn_end_deleted(SPObject *, SPObject *const owner, unsigned const handle_ix)
+{
+    char const * const attrs[] = {
+        "inkscape:connection-start", "inkscape:connection-end"};
+    owner->removeAttribute(attrs[handle_ix]);
+
+    char const * const point_attrs[] = {
+        "inkscape:connection-start-point", "inkscape:connection-end-point"};
+    owner->removeAttribute(point_attrs[handle_ix]);
+    /* I believe this will trigger sp_conn_end_href_changed. */
+}
+
+void sp_conn_end_detach(SPObject *const owner, unsigned const handle_ix)
+{
+    sp_conn_end_deleted(nullptr, owner, handle_ix);
+}
+
+void SPConnEnd::setAttacherHref(gchar const *value)
+{
+    if (g_strcmp0(value, href) != 0) {
+        g_free(href);
+        href = g_strdup(value);
+        if (!ref.try_attach(value)) {
+            g_free(href);
+            href = nullptr;
+        }
+    }
+}
+
+void SPConnEnd::setAttacherSubHref(gchar const *value)
+{
+    // TODO This could check the URI object is actually a sub-object
+    // of the set href. It should be done here and in setAttacherHref
+    if (g_strcmp0(value, sub_href) != 0) {
+        g_free(sub_href);
+        sub_href = g_strdup(value);
+        if (!sub_ref.try_attach(value)) {
+            g_free(sub_href);
+            sub_href = nullptr;
+        }
+    }
+}
+
+
+
+void sp_conn_end_href_changed(SPObject */*old_ref*/, SPObject */*ref*/,
+        SPConnEnd *connEndPtr, SPPath *const path, unsigned const handle_ix)
+{
+    g_return_if_fail(connEndPtr != nullptr);
+    SPConnEnd &connEnd = *connEndPtr;
+    connEnd._delete_connection.disconnect();
+    connEnd._transformed_connection.disconnect();
+    connEnd._group_connection.disconnect();
+
+    if (connEnd.href) {
+        SPObject *refobj = connEnd.ref.getObject();
+        if (refobj) {
+            connEnd._delete_connection
+                = refobj->connectDelete(sigc::bind(sigc::ptr_fun(&sp_conn_end_deleted),
+                                                   path, handle_ix));
+            // This allows the connector tool to dive into a group's children
+            // And connect to their children's centers.
+            SPObject *parent = refobj->parent;
+            if (SP_IS_GROUP(parent) && ! SP_IS_LAYER(parent)) {
+                connEnd._group_connection
+                    = SP_ITEM(parent)->connectModified(sigc::bind(sigc::ptr_fun(&sp_conn_end_shape_modified),
+                                                                 path));
+            }
+            connEnd._transformed_connection
+                = SP_ITEM(refobj)->connectModified(sigc::bind(sigc::ptr_fun(&sp_conn_end_shape_modified),
+                                                                 path));
+        }
+    }
+}
+
+
+
+/*
+  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 :