New LPE: Circle (with center at the first point and passing through the last point of the original path).

This is just a proof-of-concept implementation for my tech drawing proposal for GSoC '08.

(bzr r5237)

5 files changed, 168 insertions, 2 deletions

diff --git a/src/live_effects/Makefile_insert b/src/live_effects/Makefile_insert
index fee34a9d6..0c6ba4a00 100644
--- a/src/live_effects/Makefile_insert
+++ b/src/live_effects/Makefile_insert
@@ -33,5 +33,7 @@ live_effects_liblive_effects_a_SOURCES = \
 	live_effects/lpe-test-doEffect-stack.cpp	\
 	live_effects/lpe-test-doEffect-stack.h	\
 	live_effects/lpe-slant.cpp	\
-	live_effects/lpe-slant.h
+	live_effects/lpe-slant.h	\
+	live_effects/lpe-circle_with_radius.cpp	\
+	live_effects/lpe-circle_with_radius.h
 
diff --git a/src/live_effects/effect.cpp b/src/live_effects/effect.cpp
index dc43af0d5..48a3ab9ff 100644
--- a/src/live_effects/effect.cpp
+++ b/src/live_effects/effect.cpp
@@ -42,6 +42,7 @@
 #include "live_effects/lpe-test-doEffect-stack.h"
 #include "live_effects/lpe-gears.h"
 #include "live_effects/lpe-curvestitch.h"
+#include "live_effects/lpe-circle_with_radius.h"
 
 #include "nodepath.h"
 
@@ -61,7 +62,8 @@ const Util::EnumData<EffectType> LPETypeData[INVALID_LPE] = {
     {DOEFFECTSTACK_TEST,    N_("doEffect stack test"),   "doeffectstacktest"},
 #endif
     {GEARS,                 N_("Gears"),                 "gears"},
-    {CURVE_STITCH,          N_("Stitch Sub-Paths"),       "curvestitching"},
+    {CURVE_STITCH,          N_("Stitch Sub-Paths"),      "curvestitching"},
+    {CIRCLE_WITH_RADIUS,    N_("Circle (center+radius)"), "circle_with_radius"},
 };
 const Util::EnumDataConverter<EffectType> LPETypeConverter(LPETypeData, INVALID_LPE);
 
@@ -100,6 +102,9 @@ Effect::New(EffectType lpenr, LivePathEffectObject *lpeobj)
         case CURVE_STITCH:
             neweffect = (Effect*) new LPECurveStitch(lpeobj);
             break;
+        case CIRCLE_WITH_RADIUS:
+            neweffect = (Effect*) new LPECircleWithRadius(lpeobj);
+            break;
         default:
             g_warning("LivePathEffect::Effect::New   called with invalid patheffect type (%d)", lpenr);
             neweffect = NULL;
diff --git a/src/live_effects/effect.h b/src/live_effects/effect.h
index b13ec5f6d..f3143124b 100644
--- a/src/live_effects/effect.h
+++ b/src/live_effects/effect.h
@@ -62,6 +62,7 @@ enum EffectType {
 #endif
     GEARS,
     CURVE_STITCH,
+    CIRCLE_WITH_RADIUS,
     INVALID_LPE // This must be last
 };
 
diff --git a/src/live_effects/lpe-circle_with_radius.cpp b/src/live_effects/lpe-circle_with_radius.cpp
new file mode 100644
index 000000000..63e3dfa8a
--- /dev/null
+++ b/src/live_effects/lpe-circle_with_radius.cpp
@@ -0,0 +1,113 @@
+#define INKSCAPE_LPE_CIRCLE_WITH_RADIUS_CPP
+/** \file
+ * LPE <circle_with_radius> 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/CIRCLE_WITH_RADIUS/YOURNAME/g
+ *   :%s/CircleWithRadius/Yourname/g
+ *   :%s/circle_with_radius/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-circle_with_radius.h"
+#include "display/curve.h"
+#include <libnr/n-art-bpath.h>
+
+// You might need to include other 2geom files. You can add them here:
+#include <2geom/path.h>
+#include <2geom/sbasis.h>
+#include <2geom/bezier-to-sbasis.h>
+#include <2geom/d2.h>
+
+using namespace Geom;
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+LPECircleWithRadius::LPECircleWithRadius(LivePathEffectObject *lpeobject) :
+    Effect(lpeobject)//,
+    // initialise your parameters here:
+    //radius(_("Float parameter"), _("just a real number like 1.4!"), "svgname", &wr, this, 50)
+{
+    // register all your parameters here, so Inkscape knows which parameters this effect has:
+    //registerParameter( dynamic_cast<Parameter *>(&radius) );
+}
+
+LPECircleWithRadius::~LPECircleWithRadius()
+{
+
+}
+
+
+/* ########################
+ *  Choose to implement one of the doEffect functions. You can delete or comment out the others.
+*/
+
+D2<SBasis> _circle(Geom::Point center, double radius) {
+    D2<SBasis> B;
+    Linear bo = Linear(0, 2 * M_PI);
+
+    B[0] = cos(bo,2);
+    B[1] = sin(bo,2);
+
+    B = B*radius + center;
+    return B;
+}
+
+std::vector<Geom::Path>
+LPECircleWithRadius::doEffect_path (std::vector<Geom::Path> & path_in)
+{
+    std::vector<Geom::Path> path_out = std::vector<Geom::Path>();
+    Geom::Path pb;
+
+    Geom::Point center = path_in[0].initialPoint();
+    Geom::Point pt = path_in[0].finalPoint();
+
+    double radius = Geom::L2(pt - center);
+
+    pb.append(SBasisCurve(_circle(center, radius)));
+
+    path_out.push_back(pb);
+
+    return path_out;
+}
+
+/*
+
+Geom::Piecewise<Geom::D2<Geom::SBasis> >
+LPECircleWithRadius::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > & pwd2_in)
+{
+    Geom::Piecewise<Geom::D2<Geom::SBasis> > output;
+
+    output = pwd2_in;   // spice this up to make the effect actually *do* something!
+
+    return output;
+}
+
+*/
+
+/* ######################## */
+
+} //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 :
diff --git a/src/live_effects/lpe-circle_with_radius.h b/src/live_effects/lpe-circle_with_radius.h
new file mode 100644
index 000000000..e783e0aab
--- /dev/null
+++ b/src/live_effects/lpe-circle_with_radius.h
@@ -0,0 +1,45 @@
+#ifndef INKSCAPE_LPE_CIRCLE_WITH_RADIUS_H
+#define INKSCAPE_LPE_CIRCLE_WITH_RADIUS_H
+
+/** \file
+ * LPE <circle_with_radius> implementation, see lpe-circle_with_radius.cpp.
+ */
+
+/*
+ * 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/effect.h"
+#include "live_effects/parameter/parameter.h"
+#include "live_effects/parameter/path.h"
+#include "live_effects/parameter/point.h"
+
+namespace Inkscape {
+namespace LivePathEffect {
+
+class LPECircleWithRadius : public Effect {
+public:
+    LPECircleWithRadius(LivePathEffectObject *lpeobject);
+    virtual ~LPECircleWithRadius();
+
+//  Choose to implement one of the doEffect functions. You can delete or comment out the others.
+    virtual std::vector<Geom::Path> doEffect_path (std::vector<Geom::Path> & path_in);
+
+private:
+    // add the parameters for your effect here:
+    //ScalarParam radius;
+    // there are all kinds of parameters. Check the /live_effects/parameter directory which types exist!
+
+    LPECircleWithRadius(const LPECircleWithRadius&);
+    LPECircleWithRadius& operator=(const LPECircleWithRadius&);
+};
+
+} //namespace LivePathEffect
+} //namespace Inkscape
+
+#endif