port from perforce

meshToolsV5/TestApp/ObjExporter.cpp

@@ -0,0 +1,107 @@
+
+#if _DEBUG
+
+#include "ObjExporter.h"
+#include <iostream>
+#include <fstream>
+
+
+void ObjExporter::Export(mt::Mesh* mesh, const std::string& filePath)
+{
+	ObjExporter exporter(mesh);
+	exporter.Export(filePath);
+}
+
+
+ObjExporter::ObjExporter(mt::Mesh* mesh)
+	: mesh{mesh}
+{
+}
+
+void ObjExporter::Export(const std::string& filePath)
+{
+	std::ostringstream builder;
+	std::ostringstream mtlBuilder;
+	builder << "mtllib " + replace(filePath, ".obj", ".mtl") << std::endl;
+	WritePositions(builder);
+	WriteNormals(builder);
+	WriteUVs(builder);
+	WriteFaceGroups(builder, mtlBuilder);
+
+	std::ofstream objFile(filePath);
+	objFile << builder.str();
+	objFile.close();
+
+	std::ofstream mtlFile(replace(filePath, ".obj", ".mtl"));
+	mtlFile << mtlBuilder.str();
+	mtlFile.close();
+}
+
+
+void ObjExporter::WriteFaceGroups(std::ostringstream& builder, std::ostringstream& mtlBuilder)
+{
+	auto groups = mesh->GetSubMeshs();
+	for(const auto& group : groups)
+	{
+		auto materialId = group->Key;
+
+		builder << "usemtl " << materialId << std::endl;
+		builder << "g " << materialId << std::endl;
+
+		WriteFaces(builder, group->Value);
+
+		mtlBuilder << "newmtl " << materialId << std::endl;
+		mtlBuilder << "Ka  0.0 0.0 0.0" << std::endl;
+		mtlBuilder << "Kd  1.0 1.0 1.0" << std::endl;
+		mtlBuilder << "Ks  1.0 1.0 1.0" << std::endl;
+		mtlBuilder << "Ns  16.0" << std::endl;
+		mtlBuilder << "illum 0" << std::endl;
+
+		mtlBuilder << "map_Kd " << materialId << ".png" << std::endl;
+	}
+}
+
+
+void ObjExporter::WriteFaces(std::ostringstream& builder, const mt::FaceList& faces)
+{
+	for (auto face : faces)
+	{
+		auto indices = face->GetIndices(true);
+
+		builder << "f";
+		for (int i = 0; i < indices.Count(); ++i)
+		{
+			builder << " ";
+			auto index = indices[i] + 1;
+			builder << index << "/" << index << "/" << index;
+		}
+		builder << std::endl;
+	}
+}
+
+void ObjExporter::WritePositions(std::ostringstream& builder)
+{
+	for (const auto& v : mesh->GetVertices())
+	{
+		builder << "v " << v->Position.x << " " << v->Position.y << " " << v->Position.z << std::endl;
+	}
+}
+
+void ObjExporter::WriteNormals(std::ostringstream& builder)
+{
+	for (const auto& v : mesh->GetVertices())
+	{
+		auto normal = v->GetNormal();
+		builder << "vn " << normal.x << " " << normal.y << " " << normal.z << std::endl;
+	}
+}
+
+void ObjExporter::WriteUVs(std::ostringstream& builder)
+{
+	for (const auto& v : mesh->GetVertices())
+	{
+		builder << "vt " << v->UV[0] << " " << v->UV[1] << std::endl;
+	}
+}
+
+#endif