Output LWPOLYLINE objects instead of LINE for DXF export. Patch submitted by Lars Kruse

git-svn-id: http://svn.clifford.at/openscad/trunk@588 b57f626f-c46c-0410-a088-ec61d464b74c

1 files changed, 35 insertions, 18 deletions

diff --git a/src/export.cc b/src/export.cc
index 40b16d5..2b474f6 100644
--- a/src/export.cc
+++ b/src/export.cc
@@ -166,6 +166,20 @@ void export_dxf(CGAL_Nef_polyhedron *root_N, QString filename, QProgressDialog *
 	}
 
 	setlocale(LC_NUMERIC, "C"); // Ensure radix is . (not ,) in output
+
+	// Some importers (e.g. QCAD) needs a HEADER section specifying AutoCAD 2000 as 
+	// the file format for LWPOLYLINE entities to work
+	fprintf(f, "  0\n"
+					"SECTION\n"
+					"  2\n"
+					"HEADER\n"
+					"  9\n"
+					"$ACADVER\n"
+					"  1\n"
+					"AC1015\n"
+					"  0\n"
+					"ENDSEC\n");
+
 	// Some importers (e.g. Inkscape) needs a BLOCKS section to be present
 	fprintf(f, "  0\n"
 					"SECTION\n"
@@ -182,26 +196,29 @@ void export_dxf(CGAL_Nef_polyhedron *root_N, QString filename, QProgressDialog *
 	DxfData dd(*root_N);
 	for (int i=0; i<dd.paths.size(); i++)
 	{
-		for (int j=1; j<dd.paths[i].points.size(); j++) {
-			DxfData::Point *p1 = dd.paths[i].points[j-1];
-			DxfData::Point *p2 = dd.paths[i].points[j];
-			double x1 = p1->x;
-			double y1 = p1->y;
-			double x2 = p2->x;
-			double y2 = p2->y;
-			fprintf(f, "  0\n");
-			fprintf(f, "LINE\n");
-			// Some importers (e.g. Inkscape) needs a layer to be specified
-			fprintf(f, "  8\n");
-			fprintf(f, "0\n");
+		if (dd.paths[i].points.size() < 2)
+			// not a valid polygon
+			continue;
+		// Use the LWPOLYLINE class - this makes it easier to handle complete
+		// objects (as paths) in Inkscape.
+		fprintf(f, "  0\n");
+		fprintf(f, "LWPOLYLINE\n");
+		// Some importers (e.g. Inkscape) need a layer to be specified
+		fprintf(f, "  8\n");
+		fprintf(f, "0\n");
+		// number of vertices
+		fprintf(f, "  90\n");
+		fprintf(f, "%d\n", dd.paths[i].points.size());
+		// polygon flag (closed, ...)
+		fprintf(f, "  70\n");
+		fprintf(f, "%d\n", dd.paths[i].is_closed ? 1 : 0);
+		// add all points
+		for (int j=0; j<dd.paths[i].points.size(); j++) {
+			DxfData::Point *p = dd.paths[i].points[j];
 			fprintf(f, " 10\n");
-			fprintf(f, "%f\n", x1);
-			fprintf(f, " 11\n");
-			fprintf(f, "%f\n", x2);
+			fprintf(f, "%f\n", p->x);
 			fprintf(f, " 20\n");
-			fprintf(f, "%f\n", y1);
-			fprintf(f, " 21\n");
-			fprintf(f, "%f\n", y2);
+			fprintf(f, "%f\n", p->y);
 		}
 	}