OBJ class for representing .obj files.

Escape-the-Dawn/OBJ.cpp

@@ -0,0 +1,217 @@
+#include "OBJ.h"
+
+OBJ::OBJ()
+{
+	m_CurrentMaterial = nullptr;
+}
+
+void OBJ::LoadFromFile(std::string filename)
+{
+	m_Path = boost::filesystem::path(filename);
+	LOG_INFO("Parsing .obj \"%s\"", m_Path.c_str());
+
+	// http://paulbourke.net/dataformats/obj/
+	std::ifstream file(m_Path.string());
+	
+	std::string line;
+	while (std::getline(file, line)) {
+		if (line.length() == 0)
+			continue;
+
+		std::stringstream ss(line);
+
+		std::string prefix;
+		ss >> prefix;
+
+		// Ignore comments
+		if (prefix == "#")
+			continue;
+
+		// Material files
+		if (prefix == "mtllib") {
+			std::string materialFilename;
+			ss >> materialFilename;
+			m_MaterialPath = m_Path.branch_path() / materialFilename;
+			ParseMaterial();
+			continue;
+		}
+
+		// Material statement
+		if (prefix == "usemtl") {
+			std::string material;
+			ss >> material;
+			m_CurrentMaterial = &Materials[material];
+			continue;
+		}
+
+		// Vertices
+		if (prefix == "v") {
+			float x, y, z;
+			ss >> x >> y >> z;
+			Vertices.push_back(std::make_tuple(x, y, z));
+			continue;
+		}
+
+		// Normals
+		if (prefix == "vn") {
+			float x, y, z;
+			ss >> x >> y >> z;
+			Normals.push_back(std::make_tuple(x, y, z));
+		}
+
+		// Texture coordinates
+		if (prefix == "vt")	{
+			float u, v, w;
+			ss >> u >> v >> w;
+			TextureCoords.push_back(std::make_tuple(u, v, w));
+		}
+
+		// Face definitions
+		if (prefix == "f") {
+			Face face;
+			face.Material = m_CurrentMaterial;
+
+			std::string faceDefString;
+			while (ss >> faceDefString) {
+				std::stringstream ss2(faceDefString);
+				FaceDefinition faceDef = { -1, -1, -1 };
+
+				ss2 >> faceDef.VertexIndex;
+				ss2.ignore(); // Ignore first delimiter
+				if (!ss2)
+					continue;
+
+				if (ss2.peek() == '/') {
+					ss2.ignore();
+					ss2 >> faceDef.NormalIndex;
+				} else {
+					ss2 >> faceDef.TextureCoordIndex;
+					ss2.ignore();
+					ss2 >> faceDef.NormalIndex;
+				}
+				face.Definitions.push_back(faceDef);
+			}
+			Faces.push_back(face);
+		}
+	}
+}
+
+void OBJ::ParseMaterial()
+{
+	// http://paulbourke.net/dataformats/mtl/
+	std::ifstream file(m_MaterialPath.string());
+	
+	std::string currentMaterialName;
+	MaterialInfo* currentMaterial = nullptr;
+
+	std::string line;
+	while (std::getline(file, line)) {
+		if (line.length() == 0)
+			continue;
+
+		std::stringstream ss(line);
+
+		std::string prefix;
+		ss >> prefix;
+
+		// Create a new material definition
+		if (prefix == "newmtl")	{
+			MaterialInfo mat = 
+			{
+				"",
+				std::make_tuple(0.2f, 0.2f, 0.2f),
+				std::make_tuple(0.8f, 0.8f, 0.8f),
+				std::make_tuple(1.0f, 1.0f, 1.0f),
+				std::make_tuple(1.0f, 1.0f, 1.0f),
+				1.0f,
+				1.0f,
+				0.0f,
+				0,
+			};
+
+			ss >> currentMaterialName;
+			LOG_INFO("Parsing material %s", currentMaterialName);
+			Materials[currentMaterialName] = mat;
+			currentMaterial = &Materials[currentMaterialName];
+			continue;
+		}
+
+		if (!currentMaterial)
+			continue;
+
+		// Ambient color
+		if (prefix == "Ka")	{
+			float r, g, b;
+			ss >> r >> g >> b;
+			currentMaterial->AmbientColor = std::make_tuple(r, g, b);
+			continue;
+		}
+		// Diffuse color
+		if (prefix == "Kd")	{
+			float r, g, b;
+			ss >> r >> g >> b;
+			currentMaterial->DiffuseColor = std::make_tuple(r, g, b);
+			continue;
+		}
+		// Specular color
+		if (prefix == "Ks")	{
+			float r, g, b;
+			ss >> r >> g >> b;
+			currentMaterial->SpecularColor = std::make_tuple(r, g, b);
+			continue;
+		}
+		// Transmission filter
+		if (prefix == "Tf")	{
+			std::stringstream ss2;
+			ss2 << ss.str();
+
+			std::string command;
+			ss2 >> command;
+			if (command == "xyz") {
+				// TODO: "The "Ks xyz" statement specifies the specular reflectivity using CIEXYZ values."
+			}
+			else if (command == "spectral")	{
+				// TODO: "The "Tf spectral" statement specifies the transmission filter using a spectral curve."
+			} else {
+				float r, g, b;
+				ss >> r;
+				// G and B are optional
+				if (!(ss >> g >> b))
+				{
+					g = r;
+					b = r;
+				}
+				currentMaterial->TransmissionFilter = std::make_tuple(r, g, b);
+			}
+			continue;
+		}
+		// Optical density
+		if (prefix == "Ni")	{
+			ss >> currentMaterial->OpticalDensity;
+			continue;
+		}
+		// Alpha
+		if (prefix == "d" || prefix == "Tr") {
+			ss >> currentMaterial->Alpha;
+			continue;
+		}
+		// Shininess
+		if (prefix == "Ns")	{
+			ss >> currentMaterial->Shininess;
+			continue;
+		}
+		// Illumination model
+		if (prefix == "illum") {
+			int illum = 0;
+			ss >> illum;
+			currentMaterial->IlluminationModel = illum;
+			continue;
+		}
+		// Texture file
+		// TODO:
+		if (prefix == "map_Ka" || prefix == "map_Kd") {
+			ss >> currentMaterial->TextureFile;
+			continue;
+		}
+	}
+}