SVG text annotation descriptions

src/serializers/SvgSerializer.cpp

@@ -1569,7 +1569,133 @@ void SvgSerializer::resetScale() {
 	ymax = -std::numeric_limits<double>::infinity();
 }
 
+void SvgSerializer::addTextAnnotations(const drawing_key& k) {
+	auto& meta = drawing_metadata[k];
+
+	boost::optional<std::pair<double, double>> range;
+
+	if (k.first && section_data_) {
+		for (auto& sd : *section_data_) {
+			if (sd.which() == 0) {
+				const auto& plan = boost::get<horizontal_plan>(sd);
+				if (k.first == plan.storey) {
+					range = std::make_pair(plan.elevation, plan.next_elevation);
+				}
+			}
+		}
+	}
+
+	auto annotations = file->instances_by_type("IfcAnnotation");
+	for (auto& ann_ : *annotations) {
+		auto ann = (IfcUtil::IfcBaseEntity*) ann_;
+
+		auto ot = ann->get("ObjectType");
+		auto nm = ann->get("Name");
+		auto ds = ann->get("Description");
+		auto pl = ann->get("ObjectPlacement");
+
+		if (!ot->isNull() && !nm->isNull() && !ds->isNull() && !pl->isNull()) {
+			auto object_type = (std::string) *ot;
+			auto name = (std::string) *nm;
+			auto desc = (std::string) *ds;
+
+			if (object_type == "Text") {
+				IfcGeom::Kernel kernel(file);
+				gp_Trsf trsf;
+				if (kernel.convert_placement(*pl, trsf)) {
+				
+					auto v = trsf.TranslationPart();
+					if (k.first) {
+						v.ChangeCoord(1) *= -1.;
+						trsf.SetTranslationPart(v);
+					}
+
+					if (!range || (v.Z() >= range->first && v.Z() < range->second)) {
+
+						if (meta.pln_3d.Position().Direction().Dot(gp_Dir(trsf.HVectorialPart().Column(3))) > 0.99) {
+							auto svg_name = nameElement(ann);
+							path_object* po;
+							if (k.first) {
+								po = &start_path(meta.pln_3d, k.first, svg_name);
+							} else {
+								po = &start_path(meta.pln_3d, k.second, svg_name);
+							}
+
+							if (object_type.size()) {
+								// postfix the object_type for CSS matching
+								boost::replace_all(svg_name, "class=\"IfcAnnotation\"", "class=\"IfcAnnotation " + object_type + "\"");
+							}
+
+							boost::optional<double> font_size;
+							std::vector<std::string> tokens;
+							boost::split(tokens, name, boost::is_any_of("_"));
+							if (tokens.size() == 2) {
+								try {
+									font_size = boost::lexical_cast<double>(tokens.back());
+								}
+								catch (...) {}
+							}
+
+							// @todo column or row?
+							double z_rotation = gp_Dir(trsf.HVectorialPart().Column(1)).AngleWithRef(gp_Dir(1., 0., 0.), gp_Dir(0., 0., 1.));
+							z_rotation *= 180. / M_PI;
+
+							util::string_buffer path;
+							// dominant-baseline="central" is not well supported in IE.
+							// so we add a 0.35 offset to the dy of the tspans
+							path.add("            <text text-anchor=\"left\" x=\"");
+							xcoords.push_back(path.add(v.X()));
+							path.add("\" y=\"");
+							ycoords.push_back(path.add(v.Y()));
+
+							path.add("\" transform=\"rotate(");
+							path.add(z_rotation);
+							path.add(" ");
+							xcoords.push_back(path.add(v.X()));
+							path.add(" ");
+							ycoords.push_back(path.add(v.Y()));
+							path.add(")\"");
+
+							if (font_size) {
+								path.add(" font-size=\"");
+								path.add(*font_size);
+								path.add("\"");
+							}
+							path.add(">");
+
+							std::vector<std::string> labels{ desc };
+
+							for (auto lit = labels.begin(); lit != labels.end(); ++lit) {
+								const auto& l = *lit;
+								double dy = labels.begin() == lit
+									? 0.0  // align bottom
+									: 1.0; // <- dy is relative to the previous text element, so
+										   //    always 1 for successive spans.
+								path.add("<tspan x=\"");
+								xcoords.push_back(path.add(v.X()));
+								path.add("\" dy=\"");
+								path.add(boost::lexical_cast<std::string>(dy));
+								path.add("em\">");
+								path.add(l);
+								path.add("</tspan>");
+							}
+
+							path.add("</text>");
+
+							po->second.push_back(path);
+						}
+					}
+				}
+			}
+		}
+	}
+}
+
 void SvgSerializer::finalize() {
+	for (auto& p : drawing_metadata) {
+		addTextAnnotations(p.first);
+	}
+
 	for (auto& p : storey_hlr) {
 		draw_hlr(drawing_metadata[{p.first, ""}].pln_3d, { p.first, "" });
 	}

src/serializers/SvgSerializer.h

@@ -220,6 +220,7 @@ public:
 	void setDrawDoorArcs(bool b) { draw_door_arcs_ = b; }
 	void setStoreyHeightLineLength(double d) { storey_height_line_length_ = d; }
 	void setSpaceNameTransform(const std::string& v) { space_name_transform_ = v; }
+	void addTextAnnotations(const drawing_key& k);
 
 	std::array<std::array<double, 3>, 3> resize();
 	void resetScale();