1 files changed, 161 insertions, 0 deletions
diff --git a/src/live_effects/lpe-angle_bisector.cpp b/src/live_effects/lpe-angle_bisector.cpp
new file mode 100644
index 000000000..a69b6913d
--- /dev/null
+++ b/src/live_effects/lpe-angle_bisector.cpp
@@ -0,0 +1,161 @@
+#define INKSCAPE_LPE_ANGLE_BISECTOR_CPP
+/** \file
+ * LPE <angle_bisector> implementation, used as an example for a base starting class
+ * when implementing new LivePathEffects.
+ *
+ * In vi, three global search-and-replaces will let you rename everything
+ * in this and the .h file:
+ *
+ *   :%s/ANGLE_BISECTOR/YOURNAME/g
+ *   :%s/AngleBisector/Yourname/g
+ *   :%s/angle_bisector/yourname/g
+ */
+/*
+ * Authors:
+ *   Johan Engelen
+ *
+ * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include "live_effects/lpe-angle_bisector.h"
+
+// You might need to include other 2geom files. You can add them here:
+#include <2geom/path.h>
+#include <2geom/sbasis-to-bezier.h>
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+namespace AB {
+
+class KnotHolderEntityLeftEnd : public KnotHolderEntity
+{
+public:
+    virtual bool isLPEParam() { return true; }
+
+    virtual void knot_set(NR::Point const &p, NR::Point const &origin, guint state);
+    virtual NR::Point knot_get();
+};
+
+class KnotHolderEntityRightEnd : public KnotHolderEntity
+{
+public:
+    virtual bool isLPEParam() { return true; }
+
+    virtual void knot_set(NR::Point const &p, NR::Point const &origin, guint state);
+    virtual NR::Point knot_get();
+};
+
+} // namespace TtC
+
+LPEAngleBisector::LPEAngleBisector(LivePathEffectObject *lpeobject) :
+    Effect(lpeobject),
+    length_left(_("Length left"), _("Specifies the left end of the bisector"), "length-left", &wr, this, 0),
+    length_right(_("Length right"), _("Specifies the right end of the bisector"), "length-right", &wr, this, 250)
+{
+    show_orig_path = true;
+
+    registerParameter( dynamic_cast<Parameter *>(&length_left) );
+    registerParameter( dynamic_cast<Parameter *>(&length_right) );
+
+    /* we disable the handles until we support both knotholders and nodepaths */
+    //registerKnotHolderHandle(new AB::KnotHolderEntityLeftEnd(), _("Adjust the \"right\" end of the bisector"));
+    //registerKnotHolderHandle(new AB::KnotHolderEntityRightEnd(), _("Adjust the point of attachment of the bisector"));
+}
+
+LPEAngleBisector::~LPEAngleBisector()
+{
+}
+
+std::vector<Geom::Path>
+LPEAngleBisector::doEffect_path (std::vector<Geom::Path> const & path_in)
+{
+    using namespace Geom;
+
+    std::vector<Geom::Path> path_out;
+
+    // we assume that the path has >= 3 nodes
+    ptA = path_in[0].pointAt(1);
+    Point B = path_in[0].initialPoint();
+    Point C = path_in[0].pointAt(2);
+
+    double angle = angle_between(B - ptA, C - ptA);
+
+    dir = unit_vector(B - ptA) * Rotate(angle/2);
+
+    Geom::Point D = ptA - dir * length_left;
+    Geom::Point E = ptA + dir * length_right;
+
+    Piecewise<D2<SBasis> > output = Piecewise<D2<SBasis> >(D2<SBasis>(Linear(D[X], E[X]), Linear(D[Y], E[Y])));
+
+    return path_from_piecewise(output, LPE_CONVERSION_TOLERANCE);
+}
+namespace AB {
+
+// TODO: make this more generic
+static LPEAngleBisector *
+get_effect(SPItem *item)
+{
+    Effect *effect = sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item));
+    if (effect->effectType() != ANGLE_BISECTOR) {
+        g_print ("Warning: Effect is not of type LPEAngleBisector!\n");
+        return NULL;
+    }
+    return static_cast<LPEAngleBisector *>(effect);
+}
+
+void
+KnotHolderEntityLeftEnd::knot_set(NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/)
+{
+    LPEAngleBisector *lpe = get_effect(item);
+    
+    double lambda = Geom::nearest_point(p.to_2geom(), lpe->ptA, lpe->dir);
+    lpe->length_left.param_set_value(-lambda);
+
+    sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true);
+}
+
+void
+KnotHolderEntityRightEnd::knot_set(NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/)
+{
+    LPEAngleBisector *lpe = get_effect(item);
+    
+    double lambda = Geom::nearest_point(p.to_2geom(), lpe->ptA, lpe->dir);
+    lpe->length_right.param_set_value(lambda);
+
+    sp_lpe_item_update_patheffect (SP_LPE_ITEM(item), false, true);
+}
+
+NR::Point
+KnotHolderEntityLeftEnd::knot_get()
+{
+    LPEAngleBisector *lpe = get_effect(item);
+    return lpe->ptA - lpe->dir * lpe->length_left;
+}
+
+NR::Point
+KnotHolderEntityRightEnd::knot_get()
+{
+    LPEAngleBisector *lpe = get_effect(item);
+    return lpe->ptA + lpe->dir * lpe->length_right;
+}
+
+} // namespace AB
+
+/* ######################## */
+
+} //namespace LivePathEffect
+} /* namespace Inkscape */
+
+/*
+  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 :