New LPE: Parallel

(bzr r5975)

1 files changed, 170 insertions, 0 deletions

diff --git a/src/live_effects/lpe-parallel.cpp b/src/live_effects/lpe-parallel.cpp
new file mode 100644
index 000000000..51f3d3ac1
--- /dev/null
+++ b/src/live_effects/lpe-parallel.cpp
@@ -0,0 +1,170 @@
+#define INKSCAPE_LPE_PARALLEL_CPP
+/** \file
+ * LPE <parallel> implementation
+ */
+/*
+ * Authors:
+ *   Maximilian Albert
+ *
+ * Copyright (C) Johan Engelen 2007 <j.b.c.engelen@utwente.nl>
+ * Copyright (C) Maximilian Albert 2008 <maximilian.albert@gmail.com>
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include "live_effects/lpe-parallel.h"
+#include "sp-shape.h"
+#include "display/curve.h"
+
+#include <2geom/path.h>
+#include <2geom/transforms.h>
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+namespace Pl {
+
+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 Pl
+
+LPEParallel::LPEParallel(LivePathEffectObject *lpeobject) :
+    Effect(lpeobject),
+    // initialise your parameters here:
+    offset_pt(_("Offset"), _("Tadah"), "offset_pt", &wr, this),
+    length_left(_("Length left"), _("Specifies the left end of the parallel"), "length-left", &wr, this, 150),
+    length_right(_("Length right"), _("Specifies the right end of the parallel"), "length-right", &wr, this, 150)
+{
+    show_orig_path = true;
+
+    registerParameter(dynamic_cast<Parameter *>(&offset_pt));
+    registerParameter( dynamic_cast<Parameter *>(&length_left) );
+    registerParameter( dynamic_cast<Parameter *>(&length_right) );
+
+    registerKnotHolderHandle(new Pl::KnotHolderEntityLeftEnd(), _("Adjust the \"left\" end of the parallel"));
+    registerKnotHolderHandle(new Pl::KnotHolderEntityRightEnd(), _("Adjust the \"right\" end of the parallel"));
+}
+
+LPEParallel::~LPEParallel()
+{
+
+}
+
+void
+LPEParallel::doOnApply (SPLPEItem *lpeitem)
+{
+    SPCurve *curve = SP_SHAPE(lpeitem)->curve;
+
+    A = curve->first_point().to_2geom();
+    B = curve->last_point().to_2geom();
+    dir = unit_vector(B - A);
+
+    offset_pt.param_set_and_write_new_value((A + B)/2 + dir.ccw() * 100);
+}
+
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+LPEParallel::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > const & pwd2_in)
+{
+    using namespace Geom;
+
+    Piecewise<D2<SBasis> > output;
+
+    A = pwd2_in.firstValue();
+    B = pwd2_in.lastValue();
+    dir = unit_vector(B - A);
+
+    C = offset_pt - dir * length_left;
+    D = offset_pt + dir * length_right;
+
+    output = Piecewise<D2<SBasis> >(D2<SBasis>(Linear(C[X], D[X]), Linear(C[Y], D[Y])));
+    
+    return output + dir;
+}
+
+namespace Pl {
+
+// TODO: make this more generic
+static LPEParallel *
+get_effect(SPItem *item)
+{
+    Effect *effect = sp_lpe_item_get_current_lpe(SP_LPE_ITEM(item));
+    if (effect->effectType() != PARALLEL) {
+        g_print ("Warning: Effect is not of type LPEParallel!\n");
+        return NULL;
+    }
+    return static_cast<LPEParallel *>(effect);
+}
+
+void
+KnotHolderEntityLeftEnd::knot_set(NR::Point const &p, NR::Point const &/*origin*/, guint /*state*/)
+{
+    using namespace Geom;
+
+    LPEParallel *lpe = get_effect(item);
+    
+    double lambda = L2(p - lpe->offset_pt) * sgn(dot(p.to_2geom() - lpe->offset_pt, 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*/)
+{
+    using namespace Geom;
+
+    LPEParallel *lpe = get_effect(item);
+    
+    double lambda = L2(p - lpe->offset_pt) * sgn(dot(p.to_2geom() - lpe->offset_pt, 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()
+{
+    LPEParallel *lpe = get_effect(item);
+    return lpe->C;
+}
+
+NR::Point
+KnotHolderEntityRightEnd::knot_get()
+{
+    LPEParallel *lpe = get_effect(item);
+    return lpe->D;
+}
+
+} // namespace Pl
+
+/* ######################## */
+
+} //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 :