IfcOpenShell/src/ifcconvert/WavefrontObjSerializer.cpp

/********************************************************************************
 *                                                                              *
 * This file is part of IfcOpenShell.                                           *
 *                                                                              *
 * IfcOpenShell is free software: you can redistribute it and/or modify         *
 * it under the terms of the Lesser GNU General Public License as published by  *
 * the Free Software Foundation, either version 3.0 of the License, or          *
 * (at your option) any later version.                                          *
 *                                                                              *
 * IfcOpenShell is distributed in the hope that it will be useful,              *
 * but WITHOUT ANY WARRANTY; without even the implied warranty of               *
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                 *
 * Lesser GNU General Public License for more details.                          *
 *                                                                              *
 * You should have received a copy of the Lesser GNU General Public License     *
 * along with this program. If not, see <http://www.gnu.org/licenses/>.         *
 *                                                                              *
 ********************************************************************************/

#include "../ifcgeom/IfcGeomRenderStyles.h"

#include "WavefrontOBJSerializer.h"

bool WaveFrontOBJSerializer::ready() {
	return obj_stream.is_open() && mtl_stream.is_open();
}

void WaveFrontOBJSerializer::writeHeader() {
	obj_stream << "# File generated by IfcOpenShell " << IFCOPENSHELL_VERSION << std::endl;
#ifdef WIN32
	const char dir_separator = '\\';
#else
	const char dir_separator = '/';
#endif
	std::string mtl_basename = mtl_filename;
	std::string::size_type slash = mtl_basename.find_last_of(dir_separator);
	if (slash != std::string::npos) {
		mtl_basename = mtl_basename.substr(slash+1);
	}
	obj_stream << "mtllib " << mtl_basename << std::endl;
	mtl_stream << "# File generated by IfcOpenShell " << IFCOPENSHELL_VERSION << std::endl;	
}

void WaveFrontOBJSerializer::writeMaterial(const IfcGeom::SurfaceStyle& style) {			
	mtl_stream << "newmtl " << style.Name() << std::endl;
	if (style.Diffuse()) {
		const IfcGeom::SurfaceStyle::ColorComponent& diffuse = *style.Diffuse();
		mtl_stream << "Kd " << diffuse.R()  << " " << diffuse.G()  << " " << diffuse.B() << std::endl;
	}
	if (style.Specular()) {
		const IfcGeom::SurfaceStyle::ColorComponent& specular = *style.Specular();
		mtl_stream << "Ks " << specular.R()  << " " << specular.G()  << " " << specular.B() << std::endl;
	}
	if (style.Specularity()) {
		mtl_stream << "Ns " << (*style.Specularity()) << std::endl;
	}
	if (style.Transparency()) {
		const double transparency = 1.0 - *style.Transparency();
		if (transparency < 1) {
			mtl_stream << "Tr " << transparency << std::endl;
			mtl_stream << "d "  << transparency << std::endl;
			mtl_stream << "D "  << transparency << std::endl;
		}
	}
}
void WaveFrontOBJSerializer::writeTesselated(const IfcGeomObjects::IfcGeomObject* o) {
	const std::string name = o->name.empty() ? o->guid : o->name;
	obj_stream << "g " << name << std::endl;
	obj_stream << "s 1" << std::endl;
	
	const int vcount = o->mesh->verts.size() / 3;
	for ( std::vector<float>::const_iterator it = o->mesh->verts.begin(); it != o->mesh->verts.end(); ) {
		const double x = *(it++);
		const double y = *(it++);
		const double z = *(it++);
		obj_stream << "v " << x << " " << y << " " << z << std::endl;
	}
	for ( std::vector<float>::const_iterator it = o->mesh->normals.begin(); it != o->mesh->normals.end(); ) {
		const double x = *(it++);
		const double y = *(it++);
		const double z = *(it++);
		obj_stream << "vn " << x << " " << y << " " << z << std::endl;
	}

	int previous_material_id = -2;
	std::vector<int>::const_iterator material_it = o->mesh->materials.begin();

	for ( std::vector<int>::const_iterator it = o->mesh->faces.begin(); it != o->mesh->faces.end(); ) {
		
		const int material_id = *(material_it++);
		if (material_id != previous_material_id) {
			const IfcGeom::SurfaceStyle* material_style = 0;
			if (material_id >= 0) {
				material_style = o->mesh->surface_styles[material_id];
			} else {
				material_style = IfcGeom::get_default_style(o->type);
			}
			const std::string material_name = material_style->Name();
			obj_stream << "usemtl " << material_name << std::endl;
			if (materials.find(material_name) == materials.end()) {
				writeMaterial(*material_style);
				materials.insert(material_name);
			}
			previous_material_id = material_id;
		}

		const int v1 = *(it++)+vcount_total;
		const int v2 = *(it++)+vcount_total;
		const int v3 = *(it++)+vcount_total;
		obj_stream << "f " << v1 << "//" << v1 << " " << v2 << "//" << v2 << " " << v3 << "//" << v3 << std::endl;
	}
    vcount_total += vcount;
}