From 6ae65962287820b2e9c19a1bd46de815606740af Mon Sep 17 00:00:00 2001
From: johanengelen <johanengelen@users.sourceforge.net>
Date: Fri, 23 Nov 2007 23:18:12 +0000
Subject: [PATCH] LPE add experimental width control to bend path!

---
 src/live_effects/lpe-pathalongpath.cpp | 25 +++++++++++++++++--------
 src/live_effects/lpe-pathalongpath.h   |  5 ++---
 2 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/src/live_effects/lpe-pathalongpath.cpp b/src/live_effects/lpe-pathalongpath.cpp
index 7138b6faa..e552bdaad 100644
--- a/src/live_effects/lpe-pathalongpath.cpp
+++ b/src/live_effects/lpe-pathalongpath.cpp
@@ -63,22 +63,17 @@ static const Util::EnumDataConverter<PAPCopyType> PAPCopyTypeConverter(PAPCopyTy
 LPEPathAlongPath::LPEPathAlongPath(LivePathEffectObject *lpeobject) :
     Effect(lpeobject),
     bend_path(_("Bend path"), _("Path along which to bend the original path"), "bendpath", &wr, this, "M0,0 L1,0"),
+    width_path(_("Width path"), _("..."), "widthpath", &wr, this, "M0,0 L1,0"),
     copytype(_("Path copies"), _("How many copies to place along the skeleton path"), "copytype", PAPCopyTypeConverter, &wr, this, PAPCT_SINGLE_STRETCHED),
     prop_scale(_("Width"), _("Width of the path"), "prop_scale", &wr, this, 1),
     scale_y_rel(_("Width in units of length"), _("Scale the width of the path in units of its length"), "scale_y_rel", &wr, this, false),
-    spacing(_("Spacing"), _("Space between copies of the path"), "spacing", &wr, this, 0),
-    normal_offset(_("Normal offset"), "", "normal_offset", &wr, this, 0),
-    tang_offset(_("Tangential offset"), "", "tang_offset", &wr, this, 0),
     vertical_pattern(_("Original path is vertical"), "", "vertical", &wr, this, false)
 {
     registerParameter( dynamic_cast<Parameter *>(&bend_path) );
+    registerParameter( dynamic_cast<Parameter *>(&width_path) );
     registerParameter( dynamic_cast<Parameter *>(&copytype) );
     registerParameter( dynamic_cast<Parameter *>(&prop_scale) );
     registerParameter( dynamic_cast<Parameter *>(&scale_y_rel) );
-//These parameters have not been implemented yet:
-//    registerParameter( dynamic_cast<Parameter *>(&spacing) );
-//    registerParameter( dynamic_cast<Parameter *>(&normal_offset) );
-//    registerParameter( dynamic_cast<Parameter *>(&tang_offset) );
     registerParameter( dynamic_cast<Parameter *>(&vertical_pattern) );
 
     prop_scale.param_set_digits(3);
@@ -151,10 +146,15 @@ LPEPathAlongPath::doEffect_pwd2 (Geom::Piecewise<Geom::D2<Geom::SBasis> > & pwd2
         if (prop_scale != 1.0) y *= prop_scale;
     }
 
+    Piecewise<D2<SBasis> > widthpwd2 = arc_length_parametrization(Piecewise<D2<SBasis> >(width_path),2,.1);
+    D2<Piecewise<SBasis> > widthd2pw = make_cuts_independant(widthpwd2);
+    Piecewise<SBasis> width = (Piecewise<SBasis>(widthd2pw[Y]) - uskeletonbounds[Y].middle()) * wfactor;
+
+
     double offs = 0;
     Piecewise<D2<SBasis> > output;
     for (int i=0; i<nbCopies; i++){
-        output.concat(compose(uskeleton,x+offs)+y*compose(n,x+offs));
+        output.concat(compose(uskeleton,x+offs) + y*compose(width,x+offs)*compose(n,x+offs));
         offs+=pattWidth;
     }
 
@@ -187,6 +187,15 @@ LPEPathAlongPath::resetDefaults(SPItem * item)
     path.start( start );
     path.appendNew<Geom::LineSegment>( end );
     bend_path.param_set_and_write_new_value( path.toPwSb() );
+
+    Point startw(bndsX.min(), bndsY.max());
+    Point endw(bndsX.max(), bndsY.max());
+    Geom::Path pathw;
+    pathw.start( startw );
+    pathw.appendNew<Geom::LineSegment>( endw );
+    width_path.param_set_and_write_new_value( pathw.toPwSb() );
+    
+    wfactor = 1/(startw[Y]-start[Y]);
 }
 
 } // namespace LivePathEffect
diff --git a/src/live_effects/lpe-pathalongpath.h b/src/live_effects/lpe-pathalongpath.h
index d404e0f67..b75d5e227 100644
--- a/src/live_effects/lpe-pathalongpath.h
+++ b/src/live_effects/lpe-pathalongpath.h
@@ -36,13 +36,12 @@ public:
 
 private:
     PathParam  bend_path;
+    PathParam  width_path;
     EnumParam<PAPCopyType> copytype;
     ScalarParam  prop_scale;
     BoolParam scale_y_rel;
-    ScalarParam  spacing;
-    ScalarParam  normal_offset;
-    ScalarParam  tang_offset;
     BoolParam    vertical_pattern;
+    double wfactor;
 
     void on_pattern_pasted();
 
-- 
2.30.2