move transform from CGALEvaluator to Nef_polyhedron - reuse in resize(). also

move ZRemover code to cgalutils, also cleanup SVG code

9 files changed, 201 insertions, 237 deletions

diff --git a/src/CGALEvaluator.cc b/src/CGALEvaluator.cc
index b0984ce..a5a9d65 100644
--- a/src/CGALEvaluator.cc
+++ b/src/CGALEvaluator.cc
@@ -185,13 +185,6 @@ CGAL_Nef_polyhedron CGALEvaluator::applyResize(const CgaladvNode &node)
 	// Based on resize() in Giles Bathgate's RapCAD
 	CGAL_Nef_polyhedron N;
   N = applyToChildren(node, CGE_UNION);
-	if (N.isNull()) {
-		PRINT("WARNING: resize() of null polyhedron");
-		return N;
-	}
-
-	int dim = N.dim;
-	if (dim==2)	N.convertTo3d();
 
 	CGAL_Iso_cuboid_3 bb = bounding_box( *N.p3 );
 	Eigen::Matrix<NT,3,1> scale, bbox_size;
@@ -200,13 +193,18 @@ CGAL_Nef_polyhedron CGALEvaluator::applyResize(const CgaladvNode &node)
 	for (int i=0;i<3;i++)
 		if (node.newsize[i] && bbox_size[i]!=NT(0))
 			scale[i] = NT(node.newsize[i]) / NT(bbox_size[i]);
-	CGAL_Aff_transformation t( scale[0], 0,        0,        0,
-	                           0,        scale[1], 0,        0,
-	                           0,        0,        scale[2], 0,      1);
-	N.p3->transform( t );
-
-	if (dim==2) N.convertTo2d();
-
+	NT autoscale = scale.maxCoeff();
+	if (node.autosize)
+		for (int i=0;i<3;i++)
+			scale[i] = autoscale;
+
+	Eigen::Matrix4d t;
+	t << CGAL::to_double(scale[0]),           0,        0,        0,
+	     0,        CGAL::to_double(scale[1]),           0,        0,
+	     0,        0,        CGAL::to_double(scale[2]),           0,
+	     0,        0,        0,                                   1;
+
+	N.transform( Transform3d( t ) );
 	return N;
 }
 
@@ -286,56 +284,8 @@ Response CGALEvaluator::visit(State &state, const TransformNode &node)
 				PRINT("Warning: Transformation matrix contains Not-a-Number and/or Infinity - removing object.");
 				N.reset();
 			}
-
-			// Then apply transform
-			// If there is no geometry under the transform, N will be empty
-			// just silently ignore such nodes
-			if (!N.isNull()) {
-				if (N.dim == 2) {
-					// Unfortunately CGAL provides no transform method for CGAL_Nef_polyhedron2
-					// objects. So we convert in to our internal 2d data format, transform it,
-					// tesselate it and create a new CGAL_Nef_polyhedron2 from it.. What a hack!
-					
-					Eigen::Matrix2f testmat;
-					testmat << node.matrix(0,0), node.matrix(0,1), node.matrix(1,0), node.matrix(1,1);
-					if (testmat.determinant() == 0) {
-						PRINT("Warning: Scaling a 2D object with 0 - removing object");
-						N.reset();
-					}
-					else {
-						CGAL_Aff_transformation2 t(
-							node.matrix(0,0), node.matrix(0,1), node.matrix(0,3),
-							node.matrix(1,0), node.matrix(1,1), node.matrix(1,3), node.matrix(3,3));
-						
-						DxfData *dd = N.convertToDxfData();
-						for (size_t i=0; i < dd->points.size(); i++) {
-							CGAL_Kernel2::Point_2 p = CGAL_Kernel2::Point_2(dd->points[i][0], dd->points[i][1]);
-							p = t.transform(p);
-							dd->points[i][0] = to_double(p.x());
-							dd->points[i][1] = to_double(p.y());
-						}
-						
-						PolySet ps;
-						ps.is2d = true;
-						dxf_tesselate(&ps, *dd, 0, true, false, 0);
-						
-						N = evaluateCGALMesh(ps);
-						delete dd;
-					}
-				}
-				else if (N.dim == 3) {
-					if (node.matrix.matrix().determinant() == 0) {
-						PRINT("Warning: Scaling a 3D object with 0 - removing object");
-						N.reset();
-					}
-					else {
-						CGAL_Aff_transformation t(
-							node.matrix(0,0), node.matrix(0,1), node.matrix(0,2), node.matrix(0,3),
-							node.matrix(1,0), node.matrix(1,1), node.matrix(1,2), node.matrix(1,3),
-							node.matrix(2,0), node.matrix(2,1), node.matrix(2,2), node.matrix(2,3), node.matrix(3,3));
-						N.p3->transform(t);
-					}
-				}
+			else {
+				N.transform( node.matrix );
 			}
 		}
 		else {
diff --git a/src/CGAL_Nef_polyhedron.h b/src/CGAL_Nef_polyhedron.h
index 03eaaa6..cfab993 100644
--- a/src/CGAL_Nef_polyhedron.h
+++ b/src/CGAL_Nef_polyhedron.h
@@ -4,6 +4,7 @@
 #include "cgalfwd.h"
 #include "memory.h"
 #include <string>
+#include "linalg.h"
 
 class CGAL_Nef_polyhedron
 {
@@ -27,9 +28,7 @@ public:
 	int weight() const;
 	class PolySet *convertToPolyset();
 	class DxfData *convertToDxfData() const;
-	void convertTo2d();
-	void convertTo3d();
-
+	void transform( const Transform3d &matrix );
 	int dim;
 	shared_ptr<CGAL_Nef_polyhedron2> p2;
 	shared_ptr<CGAL_Nef_polyhedron3> p3;
diff --git a/src/CGAL_Nef_polyhedron_DxfData.cc b/src/CGAL_Nef_polyhedron_DxfData.cc
index e642612..50a9952 100644
--- a/src/CGAL_Nef_polyhedron_DxfData.cc
+++ b/src/CGAL_Nef_polyhedron_DxfData.cc
@@ -29,6 +29,11 @@
 #include "CGAL_Nef_polyhedron.h"
 #include "cgal.h"
 #include "cgalutils.h"
+#include <boost/variant.hpp>
+#include "polyset.h"
+#include "dxftess.h"
+#include "CGALEvaluator.h"
+#include "Tree.h"
 
 #ifdef ENABLE_CGAL
 
@@ -88,85 +93,60 @@ std::string CGAL_Nef_polyhedron::dump() const
 		return std::string("Nef Polyhedron with dimension != 2 or 3");
 }
 
-// use a try/catch block around any calls to this
-void CGAL_Nef_polyhedron::convertTo2d()
-{
-	logstream log(5);
-	if (dim!=3) return;
-	assert(this->p3);
-	ZRemover zremover;
-	CGAL_Nef_polyhedron3::Volume_const_iterator i;
-	CGAL_Nef_polyhedron3::Shell_entry_const_iterator j;
-	CGAL_Nef_polyhedron3::SFace_const_handle sface_handle;
-	for ( i = this->p3->volumes_begin(); i != this->p3->volumes_end(); ++i ) {
-		log << "<!-- volume begin. mark: " << i->mark() << " -->\n";
-		for ( j = i->shells_begin(); j != i->shells_end(); ++j ) {
-			log << "<!-- shell. mark: " << i->mark() << " -->\n";
-			sface_handle = CGAL_Nef_polyhedron3::SFace_const_handle( j );
-			this->p3->visit_shell_objects( sface_handle , zremover );
-			log << "<!-- shell. end. -->\n";
-		}
-		log << "<!-- volume end. -->\n";
-	}
-	this->p3.reset();
-	this->p2 = zremover.output_nefpoly2d;
-	this->dim = 2;
-}
-
 
-std::vector<CGAL_Point_3> face2to3(
-	CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c1,
-	CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c2,
-	CGAL_Nef_polyhedron2::Explorer explorer )
+void CGAL_Nef_polyhedron::transform( const Transform3d &matrix )
 {
-	std::vector<CGAL_Point_3> result;
-	CGAL_For_all(c1, c2) {
-		if ( explorer.is_standard( explorer.target(c1) ) ) {
-			//CGAL_Point_2e source = explorer.point( explorer.source( c1 ) );
-			CGAL_Point_2e target = explorer.point( explorer.target( c1 ) );
-			if (c1->mark()) {
-				CGAL_Point_3 tmp( target.x(), target.y(), 0 );
-				result.push_back( tmp );
+	if (!this->isNull()) {
+		if (this->dim == 2) {
+			// Unfortunately CGAL provides no transform method for CGAL_Nef_polyhedron2
+			// objects. So we convert in to our internal 2d data format, transform it,
+			// tesselate it and create a new CGAL_Nef_polyhedron2 from it.. What a hack!
+
+			Eigen::Matrix2f testmat;
+			testmat << matrix(0,0), matrix(0,1), matrix(1,0), matrix(1,1);
+			if (testmat.determinant() == 0) {
+				PRINT("Warning: Scaling a 2D object with 0 - removing object");
+				this->reset();
 			}
-		}
-	}
-	return result;
-}
-
-
-// use a try/catch block around any calls to this
-void CGAL_Nef_polyhedron::convertTo3d()
-{
-	if (dim!=2) return;
-	assert(this->p2);
-  CGAL_Nef_polyhedron2::Explorer explorer = this->p2->explorer();
-  CGAL_Nef_polyhedron2::Explorer::Face_const_iterator i;
-
-	this->p3.reset( new CGAL_Nef_polyhedron3() );
-
-	for ( i = explorer.faces_begin(); i!= explorer.faces_end(); ++i ) {
+			else {
+				CGAL_Aff_transformation2 t(
+					matrix(0,0), matrix(0,1), matrix(0,3),
+					matrix(1,0), matrix(1,1), matrix(1,3), matrix(3,3));
+
+				DxfData *dd = this->convertToDxfData();
+				for (size_t i=0; i < dd->points.size(); i++) {
+					CGAL_Kernel2::Point_2 p = CGAL_Kernel2::Point_2(dd->points[i][0], dd->points[i][1]);
+					p = t.transform(p);
+					dd->points[i][0] = to_double(p.x());
+					dd->points[i][1] = to_double(p.y());
+				}
 
-		CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c1
-			= explorer.face_cycle( i ), c2 ( c1 );
-		std::vector<CGAL_Point_3> body_pts = face2to3( c1, c2, explorer );
-		CGAL_Nef_polyhedron3 body( body_pts.begin(), body_pts.end() );
+				PolySet ps;
+				ps.is2d = true;
+				dxf_tesselate(&ps, *dd, 0, true, false, 0);
 
-		CGAL_Nef_polyhedron3 holes;
-	  CGAL_Nef_polyhedron2::Explorer::Hole_const_iterator j;
-		for ( j = explorer.holes_begin( i ); j!= explorer.holes_end( i ); ++j ) {
-			CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c3( j ), c4 ( c3 );
-			std::vector<CGAL_Point_3> hole_pts = face2to3( c3, c4, explorer );
-			CGAL_Nef_polyhedron3 hole( hole_pts.begin(), hole_pts.end() );
-			holes = holes.join( hole );
+				Tree nulltree;
+				CGALEvaluator tmpeval(nulltree);
+				CGAL_Nef_polyhedron N = tmpeval.evaluateCGALMesh(ps);
+				this->p2.reset();
+				*(this->p2) = *(N.p2);
+				delete dd;
+			}
 		}
-
-		body = body.difference( holes );
-		*(this->p3) = this->p3->join( body );
-  }
-
-	this->p2.reset();
-	this->dim = 3;
+		else if (this->dim == 3) {
+			if (matrix.matrix().determinant() == 0) {
+				PRINT("Warning: Scaling a 3D object with 0 - removing object");
+				this->reset();
+			}
+			else {
+				CGAL_Aff_transformation t(
+					matrix(0,0), matrix(0,1), matrix(0,2), matrix(0,3),
+					matrix(1,0), matrix(1,1), matrix(1,2), matrix(1,3),
+					matrix(2,0), matrix(2,1), matrix(2,2), matrix(2,3), matrix(3,3));
+				this->p3->transform(t);
+			}
+		}
+	}
 }
 
-
 #endif // ENABLE_CGAL
diff --git a/src/PolySetCGALEvaluator.cc b/src/PolySetCGALEvaluator.cc
index 0aa9e9e..5976daf 100644
--- a/src/PolySetCGALEvaluator.cc
+++ b/src/PolySetCGALEvaluator.cc
@@ -90,8 +90,21 @@ PolySet *PolySetCGALEvaluator::evaluatePolySet(const ProjectionNode &node)
 
 		log << OpenSCAD::svg_header( 480, 100000 ) << "\n";
 		try {
-			sum.convertTo2d();
-			nef_poly.p2 = sum.p2;
+      ZRemover zremover;
+      CGAL_Nef_polyhedron3::Volume_const_iterator i;
+      CGAL_Nef_polyhedron3::Shell_entry_const_iterator j;
+      CGAL_Nef_polyhedron3::SFace_const_handle sface_handle;
+      for ( i = sum.p3->volumes_begin(); i != sum.p3->volumes_end(); ++i ) {
+        log << "<!-- volume. mark: " << i->mark() << " -->\n";
+        for ( j = i->shells_begin(); j != i->shells_end(); ++j ) {
+          log << "<!-- shell. mark: " << i->mark() << " -->\n";
+          sface_handle = CGAL_Nef_polyhedron3::SFace_const_handle( j );
+          sum.p3->visit_shell_objects( sface_handle , zremover );
+          log << "<!-- shell. end. -->\n";
+        }
+        log << "<!-- volume end. -->\n";
+      }
+      nef_poly.p2 = zremover.output_nefpoly2d;
 		}	catch (const CGAL::Failure_exception &e) {
 			PRINTB("CGAL error in projection node while flattening: %s", e.what());
 		}
diff --git a/src/cgaladv.cc b/src/cgaladv.cc
index 073a908..276b59c 100644
--- a/src/cgaladv.cc
+++ b/src/cgaladv.cc
@@ -59,7 +59,7 @@ AbstractNode *CgaladvModule::evaluate(const Context *ctx, const ModuleInstantiat
 		argnames += "type", "level", "convexity";
 
 	if (type == RESIZE)
-		argnames += "newsize";
+		argnames += "newsize", "auto";
 
 	Context c(ctx);
 	c.args(argnames, argexpr, inst->argnames, inst->argvalues);
@@ -90,6 +90,8 @@ AbstractNode *CgaladvModule::evaluate(const Context *ctx, const ModuleInstantiat
 			if ( v.size() >= 2 ) node->newsize[1] = v[1].toDouble();
 			if ( v.size() >= 3 ) node->newsize[2] = v[2].toDouble();
 		}
+		Value autosize = c.lookup_variable("auto");
+		node->autosize = autosize.toBool();
 	}
 
 	node->convexity = (int)convexity.toDouble();
diff --git a/src/cgaladvnode.h b/src/cgaladvnode.h
index 097d2b4..22285da 100644
--- a/src/cgaladvnode.h
+++ b/src/cgaladvnode.h
@@ -32,6 +32,7 @@ public:
 	std::string subdiv_type;
 	int convexity, level;
 	Vector3d newsize;
+	bool autosize;
 	cgaladv_type_e type;
 };
 
diff --git a/src/cgalutils.cc b/src/cgalutils.cc
index 66d4b18..8b4c476 100644
--- a/src/cgalutils.cc
+++ b/src/cgalutils.cc
@@ -173,5 +173,56 @@ CGAL_Iso_rectangle_2e bounding_box( const CGAL_Nef_polyhedron2 &N )
 	return result;
 }
 
+void ZRemover::visit( CGAL_Nef_polyhedron3::Halffacet_const_handle hfacet )
+{
+	log << " <!-- ZRemover Halffacet visit. Mark: " << hfacet->mark() << " -->\n";
+	if ( hfacet->plane().orthogonal_direction() != this->up ) {
+		log << "  <!-- ZRemover down-facing half-facet. skipping -->\n";
+		log << " <!-- ZRemover Halffacet visit end-->\n";
+		return;
+	}
+
+	// possible optimization - throw out facets that are vertically oriented
+
+	CGAL_Nef_polyhedron3::Halffacet_cycle_const_iterator fci;
+	int contour_counter = 0;
+	CGAL_forall_facet_cycles_of( fci, hfacet ) {
+		if ( fci.is_shalfedge() ) {
+			log << " <!-- ZRemover Halffacet cycle begin -->\n";
+			CGAL_Nef_polyhedron3::SHalfedge_around_facet_const_circulator c1(fci), cend(c1);
+			std::vector<CGAL_Nef_polyhedron2::Explorer::Point> contour;
+			CGAL_For_all( c1, cend ) {
+				CGAL_Nef_polyhedron3::Point_3 point3d = c1->source()->target()->point();
+				CGAL_Nef_polyhedron2::Explorer::Point point2d( point3d.x(), point3d.y() );
+				contour.push_back( point2d );
+			}
+			if (contour.size()==0) continue;
+
+			log << " <!-- is_simple_2:" << CGAL::is_simple_2( contour.begin(), contour.end() ) << " --> \n";
+
+			tmpnef2d.reset( new CGAL_Nef_polyhedron2( contour.begin(), contour.end(), boundary ) );
+
+			if ( contour_counter == 0 ) {
+				log << " <!-- contour is a body. make union(). " << contour.size() << " points. -->\n" ;
+				*(output_nefpoly2d) += *(tmpnef2d);
+			} else {
+				log << " <!-- contour is a hole. make intersection(). " << contour.size() << " points. -->\n";
+				*(output_nefpoly2d) *= *(tmpnef2d);
+			}
+
+			/*log << "\n<!-- ======== output tmp nef: ==== -->\n"
+				<< OpenSCAD::dump_svg( *tmpnef2d ) << "\n"
+				<< "\n<!-- ======== output accumulator: ==== -->\n"
+				<< OpenSCAD::dump_svg( *output_nefpoly2d ) << "\n";*/
+
+			contour_counter++;
+		} else {
+			log << " <!-- ZRemover trivial facet cycle skipped -->\n";
+		}
+		log << " <!-- ZRemover Halffacet cycle end -->\n";
+	}
+	log << " <!-- ZRemover Halffacet visit end -->\n";
+}
+
 #endif /* ENABLE_CGAL */
 
diff --git a/src/cgalutils.h b/src/cgalutils.h
index 8f10519..6ea7711 100644
--- a/src/cgalutils.h
+++ b/src/cgalutils.h
@@ -57,55 +57,7 @@ public:
 	void visit( CGAL_Nef_polyhedron3::SHalfedge_const_handle ) {}
 	void visit( CGAL_Nef_polyhedron3::SHalfloop_const_handle ) {}
 	void visit( CGAL_Nef_polyhedron3::SFace_const_handle ) {}
-	void visit( CGAL_Nef_polyhedron3::Halffacet_const_handle hfacet ) {
-		log << " <!-- Halffacet visit. Mark: " << hfacet->mark() << " -->\n";
-		if ( hfacet->plane().orthogonal_direction() != this->up ) {
-			log << "  <!-- down-facing half-facet. skipping -->\n";
-			log << " <!-- Halffacet visit end-->\n";
-			return;
-		}
-
-		// possible optimization - throw out facets that are 'side facets' between
-		// the top & bottom of the big thin box. (i.e. mixture of z=-eps and z=eps)
-
-		CGAL_Nef_polyhedron3::Halffacet_cycle_const_iterator fci;
-		int contour_counter = 0;
-		CGAL_forall_facet_cycles_of( fci, hfacet ) {
-			if ( fci.is_shalfedge() ) {
-				CGAL_Nef_polyhedron3::SHalfedge_around_facet_const_circulator c1(fci), cend(c1);
-				std::vector<CGAL_Nef_polyhedron2::Explorer::Point> contour;
-				CGAL_For_all( c1, cend ) {
-					CGAL_Nef_polyhedron3::Point_3 point3d = c1->source()->target()->point();
-					CGAL_Nef_polyhedron2::Explorer::Point point2d( point3d.x(), point3d.y() );
-					contour.push_back( point2d );
-				}
-
-				if (contour.size()==0) continue;
-
-				log << " <!-- is_simple_2:" << CGAL::is_simple_2( contour.begin(), contour.end() ) << " --> \n";
-
-				tmpnef2d.reset( new CGAL_Nef_polyhedron2( contour.begin(), contour.end(), boundary ) );
-
-				if ( contour_counter == 0 ) {
-					log << " <!-- contour is a body. make union(). " << contour.size() << " points. -->\n" ;
-					*(output_nefpoly2d) += *(tmpnef2d);
-				} else {
-					log << " <!-- contour is a hole. make intersection(). " << contour.size() << " points. -->\n";
-					*(output_nefpoly2d) *= *(tmpnef2d);
-				}
-
-				log << "\n<!-- ======== output tmp nef: ==== -->\n"
-					<< OpenSCAD::dump_svg( *tmpnef2d ) << "\n"
-					<< "\n<!-- ======== output accumulator: ==== -->\n"
-					<< OpenSCAD::dump_svg( *output_nefpoly2d ) << "\n";
-
-				contour_counter++;
-			} else {
-				log << " <!-- trivial facet cycle skipped -->\n";
-			}
-		} // next facet cycle (i.e. next contour)
-		log << " <!-- Halffacet visit end -->\n";
-	} // visit()
+	void visit( CGAL_Nef_polyhedron3::Halffacet_const_handle hfacet );
 };
 
 
diff --git a/src/svg.cc b/src/svg.cc
index 66e5797..c1231a5 100644
--- a/src/svg.cc
+++ b/src/svg.cc
@@ -2,13 +2,13 @@
 #include "cgalutils.h"
 #include "svg.h"
 #include <boost/algorithm/string.hpp>
+#include <boost/lexical_cast.hpp>
 #include <map>
 
 namespace OpenSCAD {
 
 // SVG code
 // currently for debugging, not necessarily pretty or useful for users. (yet)
-int svg_cursor_py = 0;
 int svg_px_width = SVG_PXW;
 int svg_px_height = SVG_PXH;
 
@@ -27,6 +27,26 @@ std::string svg_label(std::string s)
 	return out.str();
 }
 
+std::string svg_styleblock(std::string strokewidth)
+{
+	std::stringstream out;
+	// halfedge: f1/f0 = face mark, b1/b0 = body or hole, m1/m0 = halfedge mark
+	out << "\
+ <style type='text/css'>\n\
+  .halfedge_f0_b1_m0 { stroke: gold; stroke-width: __STROKEW__px } \n\
+  .halfedge_f0_b1_m1 { stroke: gold; stroke-width: __STROKEW__px } \n\
+  .halfedge_f0_b0_m0 { stroke: green; stroke-width: __STROKEW__px } \n\
+  .halfedge_f0_b0_m1 { stroke: green; stroke-width: __STROKEW__px } \n\
+  .halfedge_f1_b1_m0 { stroke: gold; stroke-width: __STROKEW__px } \n\
+  .halfedge_f1_b1_m1 { stroke: gold; stroke-width: __STROKEW__px } \n\
+  .halfedge_f1_b0_m0 { stroke: green; stroke-width: __STROKEW__px } \n\
+  .halfedge_f1_b0_m1 { stroke: green; stroke-width: __STROKEW__px } \n\
+ </style>";
+	std::string tmp = out.str();
+	boost::replace_all( tmp, "__STROKEW__", strokewidth );
+	return tmp;
+}
+
 std::string svg_border()
 {
 	std::stringstream out;
@@ -93,36 +113,27 @@ std::string dump_cgal_nef_polyhedron2_face_svg(
 	CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c1,
 	CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c2,
 	CGAL_Nef_polyhedron2::Explorer explorer,
-	std::string color,
-	bool mark,
-	CGAL_Iso_rectangle_2e bbox )
+	bool facemark, bool body )
 {
+	std::stringstream style;
+	style << "halfedge_f" << facemark << "_b" << body << "_m";
+	std::string styleclass = style.str();
+
   std::stringstream out;
 	CGAL_For_all(c1, c2) {
 		if ( explorer.is_standard( explorer.target(c1) ) ) {
 			CGAL_Point_2e source = explorer.point( explorer.source( c1 ) );
 			CGAL_Point_2e target = explorer.point( explorer.target( c1 ) );
-			CGAL_Point_2e tp1 = project_svg_2to2( source, bbox );
-			CGAL_Point_2e tp2 = project_svg_2to2( target, bbox );
-			double mod=0;
-			if (color=="green") mod=10;
-			out << "      <!-- Halfedge. Mark: " << c1->mark() << " -->\n";
-      out << "       <line"
-			  << " x1='" << CGAL::to_double(tp1.x()) + mod << "'"
-			  << " y1='" << CGAL::to_double(tp1.y()) - mod << "'"
-			  << " x2='" << CGAL::to_double(tp2.x()) + mod << "'"
-			  << " y2='" << CGAL::to_double(tp2.y()) - mod << "'"
-			  << " stroke='" << color << "'";
-			if (!mark) out << " stroke-dasharray='4 4' />\n";
-			else out << " />\n";
-			// crude "arrowhead" to indicate directionality
-			out << "       <circle"
-			  << " cx='" << CGAL::to_double(tp1.x()+ (tp2.x()-tp1.x())* 7/8) + mod << "'"
-			  << " cy='" << CGAL::to_double(tp1.y()+ (tp2.y()-tp1.y())* 7/8) - mod << "'"
-			  << " r='2'"
-			  << " fill='" << color << "' stroke='" << color << "' />\n";
+			out << "    <!-- Halfedge. Mark: " << c1->mark() << " -->\n";
+			std::string he_mark = boost::lexical_cast<std::string>(c1->mark());
+      out << "     <line"
+			  << " x1='" << CGAL::to_double(source.x()) << "'"
+			  << " y1='" << CGAL::to_double(source.y()) << "'"
+			  << " x2='" << CGAL::to_double(target.x()) << "'"
+			  << " y2='" << CGAL::to_double(target.y()) << "'"
+			  << " class='" << styleclass + he_mark << "' />\n";
 		} else {
-			out << "       <!-- 2d Nef Rays - not implemented -->\n";
+			out << "     <!-- 2d Nef Rays - not implemented -->\n";
 		}
 	}
 	return out.str();
@@ -132,27 +143,27 @@ std::string dump_svg( const CGAL_Nef_polyhedron2 &N )
 {
   std::stringstream out;
   CGAL_Nef_polyhedron2::Explorer explorer = N.explorer();
-
 	CGAL_Iso_rectangle_2e bbox = bounding_box( N );
-
   CGAL_Nef_polyhedron2::Explorer::Face_const_iterator i;
-  out << " <svg y='" << svg_cursor_py << "' width='" << svg_px_width
-		<< "' height='" << svg_px_height
-		<< "' xmlns='http://www.w3.org/2000/svg' version='1.1'>\n";
-	out << svg_border() << "\n" << svg_axes() << "\n";
-	svg_cursor_py += svg_px_height;
+
+	std::string linewidth = "0.05";
+
+	out << "<!--CGAL_Nef_polyhedron2 dump begin-->\n";
+	out << svg_header() << "\n" << svg_styleblock( linewidth ) << "\n";
 
 	for ( i = explorer.faces_begin(); i!= explorer.faces_end(); ++i ) {
 			out << "  <!-- face begin. mark: " << i->mark() << "  -->\n";
+			out << "   <!-- body begin -->\n";
 			CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c1
 				= explorer.face_cycle( i ), c2 ( c1 );
-			out << dump_cgal_nef_polyhedron2_face_svg( c1, c2, explorer, "red", i->mark(), bbox );
+			out << dump_cgal_nef_polyhedron2_face_svg( c1, c2, explorer, i->mark(), true );
+			out << "   <!-- body end -->\n";
 
 		  CGAL_Nef_polyhedron2::Explorer::Hole_const_iterator j;
 			for ( j = explorer.holes_begin( i ); j!= explorer.holes_end( i ); ++j ) {
 				out << "   <!-- hole begin. mark: " << j->mark() << " -->\n";
 				CGAL_Nef_polyhedron2::Explorer::Halfedge_around_face_const_circulator c3( j ), c4 ( c3 );
-				out << dump_cgal_nef_polyhedron2_face_svg( c3, c4, explorer, "green", j->mark(), bbox );
+				out << dump_cgal_nef_polyhedron2_face_svg( c3, c4, explorer, "green", j->mark() );
 				out << "   <!-- hole end -->\n";
 			}
 			out << "  <!-- face end -->\n";
@@ -182,13 +193,13 @@ public:
 	void visit( CGAL_Nef_polyhedron3::Halffacet_const_handle hfacet )
 	{
 		int contour_count = 0;
-		out << "  <!-- Halffacet. Mark: " << (*hfacet).mark() << " -->\n";
+		out << "  <!-- Halffacet visit. Mark: " << (*hfacet).mark() << " -->\n";
 		std::string color = "gold";
 		if (!(*hfacet).mark()) color = "green";
 		CGAL_Nef_polyhedron3::Halffacet_cycle_const_iterator i;
 		CGAL_forall_facet_cycles_of( i, hfacet ) {
 			CGAL_Nef_polyhedron3::SHalfloop_const_handle shl_handle;
-			out << "   <!-- Halffacet cycle: -->\n";
+			out << "   <!-- Halffacet cycle begin: -->\n";
 			if ( contour_count == 0 ) {
 				out << "    <!-- Body contour:--> \n";
 			} else {
@@ -196,13 +207,15 @@ public:
 			}
 			CGAL_Nef_polyhedron3::SHalfedge_around_facet_const_circulator c1(i), c2(c1);
 			CGAL_For_all( c1, c2 ) {
-				out << "     <line";
 				// don't know why we use source()->source(), except thats what CGAL does internally
 				CGAL_Point_3 source = c1->source()->source()->point();
 				CGAL_Point_3 target = c1->source()->target()->point();
 				CGAL_Point_2e tp1 = project_svg_3to2 ( source, bbox );
 				CGAL_Point_2e tp2 = project_svg_3to2 ( target, bbox );
-				out << " "
+        out << "     <!-- " << CGAL::to_double(source.x()) << ","
+          << CGAL::to_double(source.y()) << ","
+          << CGAL::to_double(source.z()) << " -->\n";
+				out << "     <line "
 					<< "x1='" << CGAL::to_double(tp1.x()) << "' "
 					<< "y1='" << CGAL::to_double(tp1.y()) << "' "
 					<< "x2='" << CGAL::to_double(tp2.x()) << "' "
@@ -212,31 +225,34 @@ public:
 				else out << " />\n";
 			}
 			contour_count++;
-		} // next facet cycle (i.e. next contour)
-	} // visit()
-
+			out << "   <!-- Halffacet cycle end -->\n";
+		}
+		out << "  <!-- Halffacet visit end -->\n";
+	}
 };
 
 
 std::string dump_svg( const CGAL_Nef_polyhedron3 &N )
 {
   std::stringstream out;
-	out << svg_header() << "\n" << svg_border() << "\n" << svg_axes() << "\n";
+	std::string linewidth = "0.05";
 	out << "<!--CGAL_Nef_polyhedron3 dump begin-->\n";
+	out << svg_header() << "\n" << svg_border() << "\n";
+	out << svg_styleblock( linewidth ) << "\n" << svg_axes() << "\n";
 
   CGAL_Nef_polyhedron3::Volume_const_iterator c;
   CGAL_forall_volumes(c,N) {
-    out << " <!--Processing volume...-->\n";
+    out << " <!--Volume begin-->\n";
     out << "  <!--Mark: " << (*c).mark() << "-->\n";
     CGAL_Nef_polyhedron3::Shell_entry_const_iterator it;
     CGAL_forall_shells_of(it,c) {
-      out << "  <!--Processing shell...-->\n";
+      out << "  <!--Shell begin-->\n";
       NefPoly3_dumper_svg dumper_svg(N);
       N.visit_shell_objects(CGAL_Nef_polyhedron3::SFace_const_handle(it), dumper_svg );
 			out << dumper_svg.out.str();
-      out << "  <!--Processing shell end-->\n";
+      out << "  <!--Shell end-->\n";
     }
-    out << " <!--Processing volume end-->\n";
+    out << " <!--Volume end-->\n";
   }
   out << "<!--CGAL_Nef_polyhedron3 dump end-->\n";
 	out << "</svg>";