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parse units and precision when a file is opened from the python interface

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This commit is contained in:
Thomas Krijnen
2014-07-10 16:51:26 +02:00
parent 607f7bd015
commit f7adeb9cc1
5 changed files with 149 additions and 138 deletions
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src/ifcgeom/IfcGeom.h
+3 -1
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@@ -82,6 +82,7 @@ namespace IfcGeom {
const int DISABLE_OPENING_SUBTRACTIONS = 1 << 0; const int DISABLE_OPENING_SUBTRACTIONS = 1 << 0;
const int DISABLE_OBJECT_PLACEMENT = 1 << 1; const int DISABLE_OBJECT_PLACEMENT = 1 << 1;
const int SEW_SHELLS = 1 << 2; const int SEW_SHELLS = 1 << 2;
const int CONVERT_TO_METERS = 1 << 3;
bool convert_wire_to_face(const TopoDS_Wire& wire, TopoDS_Face& face); bool convert_wire_to_face(const TopoDS_Wire& wire, TopoDS_Face& face);
bool convert_curve_to_wire(const Handle(Geom_Curve)& curve, TopoDS_Wire& wire); bool convert_curve_to_wire(const Handle(Geom_Curve)& curve, TopoDS_Wire& wire);
@@ -107,7 +108,8 @@ namespace IfcGeom {
void apply_tolerance(TopoDS_Shape& s, double t); void apply_tolerance(TopoDS_Shape& s, double t);
void SetValue(GeomValue var, double value); void SetValue(GeomValue var, double value);
double GetValue(GeomValue var); double GetValue(GeomValue var);
std::string create_brep_data(Ifc2x3::IfcProduct* s, unsigned int settings); std::string create_brep_data(IfcSchema::IfcProduct* s, unsigned int settings);
void initialize_units_and_precision(IfcSchema::IfcProject* proj, double& unit_magnitude, std::string& unit_name);
bool fill_nonmanifold_wires_with_planar_faces(TopoDS_Shape& shape); bool fill_nonmanifold_wires_with_planar_faces(TopoDS_Shape& shape);
IfcSchema::IfcProductDefinitionShape* tesselate(TopoDS_Shape& shape, double deflection, IfcEntities es); IfcSchema::IfcProductDefinitionShape* tesselate(TopoDS_Shape& shape, double deflection, IfcEntities es);
src/ifcgeom/IfcGeomFunctions.cpp
+133 -7
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@@ -690,10 +690,11 @@ bool IfcGeom::fill_nonmanifold_wires_with_planar_faces(TopoDS_Shape& shape) {
return true; return true;
} }
std::string IfcGeom::create_brep_data(Ifc2x3::IfcProduct* ifc_product, unsigned int settings) { std::string IfcGeom::create_brep_data(IfcSchema::IfcProduct* ifc_product, unsigned int settings) {
const bool no_openings = !!(settings & DISABLE_OPENING_SUBTRACTIONS); const bool no_openings = !!(settings & DISABLE_OPENING_SUBTRACTIONS);
const bool no_placement = !!(settings & DISABLE_OBJECT_PLACEMENT); const bool no_placement = !!(settings & DISABLE_OBJECT_PLACEMENT);
const bool sew_shells = !!(settings & SEW_SHELLS); const bool sew_shells = !!(settings & SEW_SHELLS);
const bool convert_to_meters = !!(settings & CONVERT_TO_METERS);
const double old_max_faces_to_sew = GetValue(GV_MAX_FACES_TO_SEW); const double old_max_faces_to_sew = GetValue(GV_MAX_FACES_TO_SEW);
const double inf = std::numeric_limits<double>::infinity(); const double inf = std::numeric_limits<double>::infinity();
@@ -703,13 +704,13 @@ std::string IfcGeom::create_brep_data(Ifc2x3::IfcProduct* ifc_product, unsigned
if (ifc_product->hasRepresentation()) { if (ifc_product->hasRepresentation()) {
Ifc2x3::IfcProductRepresentation* prod_rep = ifc_product->Representation(); IfcSchema::IfcProductRepresentation* prod_rep = ifc_product->Representation();
Ifc2x3::IfcRepresentation::list li = prod_rep->Representations(); IfcSchema::IfcRepresentation::list li = prod_rep->Representations();
Ifc2x3::IfcShapeRepresentation* shape_rep = 0; IfcSchema::IfcShapeRepresentation* shape_rep = 0;
for (Ifc2x3::IfcRepresentation::it i = li->begin(); i != li->end(); ++i) { for (IfcSchema::IfcRepresentation::it i = li->begin(); i != li->end(); ++i) {
const std::string representation_identifier = (*i)->RepresentationIdentifier(); const std::string representation_identifier = (*i)->RepresentationIdentifier();
if ((*i)->is(Ifc2x3::Type::IfcShapeRepresentation) && (representation_identifier == "Body" || representation_identifier == "Facetation")) { if ((*i)->is(IfcSchema::Type::IfcShapeRepresentation) && (representation_identifier == "Body" || representation_identifier == "Facetation")) {
shape_rep = (Ifc2x3::IfcShapeRepresentation*) *i; shape_rep = (IfcSchema::IfcShapeRepresentation*) *i;
break; break;
} }
} }
@@ -781,6 +782,11 @@ std::string IfcGeom::create_brep_data(Ifc2x3::IfcProduct* ifc_product, unsigned
BRepBuilderAPI_GTransform(s,trsf,true).Shape(); BRepBuilderAPI_GTransform(s,trsf,true).Shape();
builder.Add(compound,moved_shape); builder.Add(compound,moved_shape);
} }
if (GetValue(GV_LENGTH_UNIT) != 1. && !convert_to_meters) {
gp_Trsf length_unit_scale;
length_unit_scale.SetScaleFactor(1. / GetValue(GV_LENGTH_UNIT));
compound.Move(length_unit_scale);
}
std::stringstream sstream; std::stringstream sstream;
BRepTools::Write(compound,sstream); BRepTools::Write(compound,sstream);
brep_data = sstream.str(); brep_data = sstream.str();
@@ -792,3 +798,123 @@ std::string IfcGeom::create_brep_data(Ifc2x3::IfcProduct* ifc_product, unsigned
return brep_data; return brep_data;
} }
double UnitPrefixToValue( IfcSchema::IfcSIPrefix::IfcSIPrefix v ) {
if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_EXA ) return (double) 1e18;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_PETA ) return (double) 1e15;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_TERA ) return (double) 1e12;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_GIGA ) return (double) 1e9;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MEGA ) return (double) 1e6;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_KILO ) return (double) 1e3;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_HECTO ) return (double) 1e2;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_DECA ) return (double) 1;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_DECI ) return (double) 1e-1;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_CENTI ) return (double) 1e-2;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MILLI ) return (double) 1e-3;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MICRO ) return (double) 1e-6;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_NANO ) return (double) 1e-9;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_PICO ) return (double) 1e-12;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_FEMTO ) return (double) 1e-15;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_ATTO ) return (double) 1e-18;
else return 1.0f;
}
void IfcGeom::initialize_units_and_precision(IfcSchema::IfcProject* proj, double& unit_magnitude, std::string& unit_name) {
// IfcOpenShell measures internally in meters, therefore a conversion factor
// is obtained based on the length unit in the file.
// Set default units, set length to meters, angles to undefined
IfcGeom::SetValue(IfcGeom::GV_LENGTH_UNIT,1.0);
IfcGeom::SetValue(IfcGeom::GV_PLANEANGLE_UNIT,-1.0);
IfcUtil::IfcAbstractSelect::list units = IfcUtil::IfcAbstractSelect::list();
try {
IfcSchema::IfcUnitAssignment* unit_assignment = proj->UnitsInContext();
units = unit_assignment->Units();
} catch (const IfcParse::IfcException&) {}
try {
for ( IfcUtil::IfcAbstractSelect::it it = units->begin(); it != units->end(); ++ it ) {
std::string current_unit_name = "";
const IfcUtil::IfcAbstractSelect::ptr base = *it;
IfcSchema::IfcSIUnit::ptr unit = IfcSchema::IfcSIUnit::ptr();
double value = 1.0f;
if ( base->is(IfcSchema::Type::IfcConversionBasedUnit) ) {
const IfcSchema::IfcConversionBasedUnit::ptr u = reinterpret_pointer_cast<IfcUtil::IfcAbstractSelect,IfcSchema::IfcConversionBasedUnit>(base);
current_unit_name = u->Name();
const IfcSchema::IfcMeasureWithUnit::ptr u2 = u->ConversionFactor();
IfcSchema::IfcUnit u3 = u2->UnitComponent();
if ( u3->is(IfcSchema::Type::IfcSIUnit) ) {
unit = (IfcSchema::IfcSIUnit*) u3;
}
IfcSchema::IfcValue v = u2->ValueComponent();
const double f = *((IfcUtil::IfcBaseEntity*)v)->entity->getArgument(0);
value *= f;
} else if ( base->is(IfcSchema::Type::IfcSIUnit) ) {
unit = reinterpret_pointer_cast<IfcUtil::IfcAbstractSelect,IfcSchema::IfcSIUnit>(base);
}
if ( unit ) {
if ( unit->hasPrefix() ) {
value *= UnitPrefixToValue(unit->Prefix());
}
IfcSchema::IfcUnitEnum::IfcUnitEnum type = unit->UnitType();
if ( type == IfcSchema::IfcUnitEnum::IfcUnit_LENGTHUNIT ) {
IfcGeom::SetValue(IfcGeom::GV_LENGTH_UNIT,value);
if (current_unit_name.empty()) {
if (unit->hasPrefix()) {
current_unit_name = IfcSchema::IfcSIPrefix::ToString(unit->Prefix());
}
current_unit_name += IfcSchema::IfcSIUnitName::ToString(unit->Name());
}
unit_magnitude = value;
unit_name = current_unit_name;
} else if ( type == IfcSchema::IfcUnitEnum::IfcUnit_PLANEANGLEUNIT ) {
IfcGeom::SetValue(IfcGeom::GV_PLANEANGLE_UNIT,value);
}
}
}
} catch (const IfcParse::IfcException& ex) {
std::stringstream ss;
ss << "Failed to determine unit information '" << ex.what() << "'";
Logger::Message(Logger::LOG_ERROR, ss.str());
}
// Boolean operations rely on a precision value for vertex and face coincedence. This
// value is obtained from the IfcGeometricRepresentationContexts in the file.
// Set an initial guess in case reading from file fails.
IfcGeom::SetValue(IfcGeom::GV_PRECISION, 0.00001);
try {
IfcSchema::IfcRepresentationContext::list rep_contexts = proj->RepresentationContexts();
// Currently, IfcGeometricRepresentationContext aren't used as much as they should be
// in the evaluation of shape representations, hence, we try to find the one with the
// lowest precision. Typically, a value of 1e-5 is encountered. This value is applied
// to all TopoDS_Shapes generated by one of the IfcGeom::convert() functions.
// TODO: Many of the empirically found tolerances should probably be substituted by
// one that is defined in the model file.
double lowest_precision_encountered = std::numeric_limits<double>::infinity();
bool any_precision_encountered = false;
for (IfcSchema::IfcRepresentationContext::it it = rep_contexts->begin(); it != rep_contexts->end(); ++it) {
if ((*it)->is(IfcSchema::Type::IfcGeometricRepresentationContext)) {
IfcSchema::IfcGeometricRepresentationContext* rep_context = (IfcSchema::IfcGeometricRepresentationContext*)*it;
if (rep_context->is(IfcSchema::Type::IfcGeometricRepresentationSubContext)) continue;
if (rep_context->hasPrecision()) {
const double precision = rep_context->Precision();
if (precision < lowest_precision_encountered) {
any_precision_encountered = true;
lowest_precision_encountered = precision;
}
}
}
}
if (any_precision_encountered) {
IfcGeom::SetValue(IfcGeom::GV_PRECISION, lowest_precision_encountered);
}
} catch (const IfcParse::IfcException& ex) {
std::stringstream ss;
ss << "Failed to determine precision value '" << ex.what() << "'";
Logger::Message(Logger::LOG_ERROR, ss.str());
}
}
src/ifcgeom/IfcGeomObjects.cpp
+5 -130
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@@ -587,140 +587,16 @@ const IfcGeomObjects::IfcGeomBrepDataObject* IfcGeomObjects::GetBrepData() {
} }
return current_brep_data_obj; return current_brep_data_obj;
} }
double UnitPrefixToValue( IfcSchema::IfcSIPrefix::IfcSIPrefix v ) {
if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_EXA ) return (double) 1e18;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_PETA ) return (double) 1e15;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_TERA ) return (double) 1e12;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_GIGA ) return (double) 1e9;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MEGA ) return (double) 1e6;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_KILO ) return (double) 1e3;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_HECTO ) return (double) 1e2;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_DECA ) return (double) 1;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_DECI ) return (double) 1e-1;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_CENTI ) return (double) 1e-2;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MILLI ) return (double) 1e-3;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_MICRO ) return (double) 1e-6;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_NANO ) return (double) 1e-9;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_PICO ) return (double) 1e-12;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_FEMTO ) return (double) 1e-15;
else if ( v == IfcSchema::IfcSIPrefix::IfcSIPrefix_ATTO ) return (double) 1e-18;
else return 1.0f;
}
void IfcGeomObjects::InitPrecision() {
IfcGeom::SetValue(IfcGeom::GV_PRECISION, 0.00001);
try {
IfcSchema::IfcGeometricRepresentationContext::list rep_contexts = ifc_file->EntitiesByType<IfcSchema::IfcGeometricRepresentationContext>();
// Currently, IfcGeometricRepresentationContext aren't used as much as they should be
// in the evaluation of shape representations, hence, we try to find the one with the
// lowest precision. Typically, a value of 1e-5 is encountered. This value is applied
// to all TopoDS_Shapes generated by one of the IfcGeom::convert() functions.
// TODO: Many of the empirically found tolerances should probably be substituted by
// one that is defined in the model file.
double lowest_precision_encountered = std::numeric_limits<double>::infinity();
bool any_precision_encountered = false;
for (IfcSchema::IfcGeometricRepresentationContext::it it = rep_contexts->begin(); it != rep_contexts->end(); ++it) {
IfcSchema::IfcGeometricRepresentationContext* rep_context = *it;
if (rep_context->is(IfcSchema::Type::IfcGeometricRepresentationSubContext)) continue;
if (rep_context->hasPrecision()) {
const double precision = rep_context->Precision();
if (precision < lowest_precision_encountered) {
any_precision_encountered = true;
lowest_precision_encountered = precision;
}
}
}
if (any_precision_encountered) {
IfcGeom::SetValue(IfcGeom::GV_PRECISION, lowest_precision_encountered);
}
} catch (const IfcParse::IfcException& ex) {
std::stringstream ss;
ss << "Failed to determine precision value '" << ex.what() << "'";
Logger::Message(Logger::LOG_ERROR, ss.str());
}
}
static std::string unit_name = "METER"; static std::string unit_name = "METER";
static float unit_magnitude = 1.0f; static float unit_magnitude = 1.0f;
void IfcGeomObjects::InitUnits() { void IfcGeomObjects::InitUnits() {
// Set default units, set length to meters, angles to undefined IfcSchema::IfcProject::list projects = ifc_file->EntitiesByType<IfcSchema::IfcProject>();
IfcGeom::SetValue(IfcGeom::GV_LENGTH_UNIT,1.0); if (projects->Size() == 1) {
IfcGeom::SetValue(IfcGeom::GV_PLANEANGLE_UNIT,-1.0); double unit_magnitude_double;
IfcGeom::initialize_units_and_precision(*projects->begin(), unit_magnitude_double, unit_name);
IfcSchema::IfcUnitAssignment::list unit_assignments = ifc_file->EntitiesByType<IfcSchema::IfcUnitAssignment>(); unit_magnitude = static_cast<float>(unit_magnitude_double);
IfcUtil::IfcAbstractSelect::list units = IfcUtil::IfcAbstractSelect::list();
try {
if ( unit_assignments->Size() ) {
IfcSchema::IfcUnitAssignment::ptr unit_assignment = *unit_assignments->begin();
units = unit_assignment->Units();
}
} catch (const IfcParse::IfcException&) {}
if (!units) {
// No units eh... Since tolerances and deflection are specified internally in meters
// we will try to find another indication of the model size.
IfcSchema::IfcExtrudedAreaSolid::list extrusions = ifc_file->EntitiesByType<IfcSchema::IfcExtrudedAreaSolid>();
if ( ! extrusions->Size() ) return;
double max_height = -1.0f;
for ( IfcSchema::IfcExtrudedAreaSolid::it it = extrusions->begin(); it != extrusions->end(); ++ it ) {
try {
const double depth = (*it)->Depth();
if ( depth > max_height ) max_height = depth;
} catch (const IfcParse::IfcException&) {}
}
if ( max_height > 100.0f ) {
IfcGeom::SetValue(IfcGeom::GV_LENGTH_UNIT,0.001);
Logger::Message(Logger::LOG_NOTICE, "Guessed length unit to be in millimeters based on extrusion depth");
}
return;
}
try {
for ( IfcUtil::IfcAbstractSelect::it it = units->begin(); it != units->end(); ++ it ) {
std::string current_unit_name = "";
const IfcUtil::IfcAbstractSelect::ptr base = *it;
IfcSchema::IfcSIUnit::ptr unit = IfcSchema::IfcSIUnit::ptr();
double value = 1.0f;
if ( base->is(IfcSchema::Type::IfcConversionBasedUnit) ) {
const IfcSchema::IfcConversionBasedUnit::ptr u = reinterpret_pointer_cast<IfcUtil::IfcAbstractSelect,IfcSchema::IfcConversionBasedUnit>(base);
current_unit_name = u->Name();
const IfcSchema::IfcMeasureWithUnit::ptr u2 = u->ConversionFactor();
IfcSchema::IfcUnit u3 = u2->UnitComponent();
if ( u3->is(IfcSchema::Type::IfcSIUnit) ) {
unit = (IfcSchema::IfcSIUnit*) u3;
}
IfcSchema::IfcValue v = u2->ValueComponent();
const double f = *((IfcUtil::IfcBaseEntity*)v)->entity->getArgument(0);
value *= f;
} else if ( base->is(IfcSchema::Type::IfcSIUnit) ) {
unit = reinterpret_pointer_cast<IfcUtil::IfcAbstractSelect,IfcSchema::IfcSIUnit>(base);
}
if ( unit ) {
if ( unit->hasPrefix() ) {
value *= UnitPrefixToValue(unit->Prefix());
}
IfcSchema::IfcUnitEnum::IfcUnitEnum type = unit->UnitType();
if ( type == IfcSchema::IfcUnitEnum::IfcUnit_LENGTHUNIT ) {
IfcGeom::SetValue(IfcGeom::GV_LENGTH_UNIT,value);
if (current_unit_name.empty()) {
if (unit->hasPrefix()) {
current_unit_name = IfcSchema::IfcSIPrefix::ToString(unit->Prefix());
}
current_unit_name += IfcSchema::IfcSIUnitName::ToString(unit->Name());
}
unit_magnitude = value;
unit_name = current_unit_name;
} else if ( type == IfcSchema::IfcUnitEnum::IfcUnit_PLANEANGLEUNIT ) {
IfcGeom::SetValue(IfcGeom::GV_PLANEANGLE_UNIT,value);
}
}
}
} catch (const IfcParse::IfcException& ex) {
std::stringstream ss;
ss << "Failed to determine unit information '" << ex.what() << "'";
Logger::Message(Logger::LOG_ERROR, ss.str());
} }
} }
@@ -729,7 +605,6 @@ bool IfcGeomObjects::Init(const std::string fn) {
} }
bool _Init() { bool _Init() {
IfcGeomObjects::InitUnits(); IfcGeomObjects::InitUnits();
IfcGeomObjects::InitPrecision();
shapereps = ifc_file->EntitiesByType<IfcSchema::IfcShapeRepresentation>(); shapereps = ifc_file->EntitiesByType<IfcSchema::IfcShapeRepresentation>();
if ( ! shapereps ) return false; if ( ! shapereps ) return false;
src/ifcwrap/Interface.h
+7
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@@ -99,6 +99,12 @@ namespace IfcParse {
IfcParse::IfcFile* open(const std::string& s) { IfcParse::IfcFile* open(const std::string& s) {
IfcParse::IfcFile* f = new IfcParse::IfcFile(); IfcParse::IfcFile* f = new IfcParse::IfcFile();
f->Init(s); f->Init(s);
IfcEntities projects = f->EntitiesByType("IfcProject");
if (projects->Size() == 1) {
double unit_magnitude;
std::string unit_name;
IfcGeom::initialize_units_and_precision((IfcSchema::IfcProject*)*projects->begin(), unit_magnitude, unit_name);
}
return f; return f;
} }
@@ -115,6 +121,7 @@ namespace IfcParse {
const int DISABLE_OPENING_SUBTRACTIONS = 1 << 0; const int DISABLE_OPENING_SUBTRACTIONS = 1 << 0;
const int DISABLE_OBJECT_PLACEMENT = 1 << 1; const int DISABLE_OBJECT_PLACEMENT = 1 << 1;
const int SEW_SHELLS = 1 << 2; const int SEW_SHELLS = 1 << 2;
const int CONVERT_TO_METERS = 1 << 3;
} }
std::ostream& operator<< (std::ostream& os, const IfcParse::IfcFile& f); std::ostream& operator<< (std::ostream& os, const IfcParse::IfcFile& f);
src/ifcwrap/ifc.py
+1
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@@ -104,3 +104,4 @@ def clean(): return ifc_wrapper.clean()
DISABLE_OPENING_SUBTRACTIONS = ifc_wrapper.DISABLE_OPENING_SUBTRACTIONS DISABLE_OPENING_SUBTRACTIONS = ifc_wrapper.DISABLE_OPENING_SUBTRACTIONS
DISABLE_OBJECT_PLACEMENT = ifc_wrapper.DISABLE_OBJECT_PLACEMENT DISABLE_OBJECT_PLACEMENT = ifc_wrapper.DISABLE_OBJECT_PLACEMENT
SEW_SHELLS = ifc_wrapper.SEW_SHELLS SEW_SHELLS = ifc_wrapper.SEW_SHELLS
CONVERT_TO_METERS = ifc_wrapper.CONVERT_TO_METERS