Extended OBJ loader to parse specular and normal maps

src/Model.cpp

@@ -18,7 +18,7 @@ Model::Model(OBJ &obj, ResourceManager* rm)
 		{
 			currentMaterial = face.Material;
 			// Load texture
-			auto texture = std::shared_ptr<Texture>(rm->Load<Texture>("Texture", currentMaterial->TextureFile));
+			auto texture = std::shared_ptr<Texture>(rm->Load<Texture>("Texture", currentMaterial->DiffuseTexture.FileName));
 			// TODO: Load material parameters
 			// Create new texture group (start index of new group is upcoming index)
 			TextureGroup texGroup = { texture, index, index };

src/OBJ.cpp

@@ -126,9 +126,11 @@ void OBJ::ParseMaterial()
 	std::string currentMaterialName;
 	MaterialInfo* currentMaterial = nullptr;
 
+	unsigned int currentLine = 0;
 	std::string line;
 	while (std::getline(file, line))
 	{
+		currentLine++;
 		if (line.length() == 0)
 			continue;
 
@@ -140,19 +142,7 @@ void OBJ::ParseMaterial()
 		// Create a new material definition
 		if (prefix == "newmtl")
 		{
-			MaterialInfo mat =
+			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.c_str());
 			Materials[currentMaterialName] = mat;
@@ -243,14 +233,177 @@ void OBJ::ParseMaterial()
 			currentMaterial->IlluminationModel = illum;
 			continue;
 		}
-		// Texture file
+		// Diffuse texture
-		// TODO:
+		if (prefix == "map_Kd")
-		if (prefix == "map_Ka" || prefix == "map_Kd")
 		{
-			std::string textureFile;
+			MaterialInfo::ColorMap colorMap;
-			ss >> textureFile;
+
-			currentMaterial->TextureFile = (m_MaterialPath.branch_path() / textureFile).string();
+			std::string fileName;
+			std::string arg;
+			while (ss >> arg)
+			{
+				ParseColorMap(currentLine, ss, prefix, arg, colorMap);
+			}
+
+			// HACK: Should we really have to specify the full path here?
+			colorMap.FileName = (m_MaterialPath.branch_path() / colorMap.FileName).string();
+			currentMaterial->DiffuseTexture = colorMap;
+			continue;
+		}
+		// Specular map
+		if (prefix == "map_Ks")
+		{
+			MaterialInfo::ColorMap colorMap;
+
+			std::string fileName;
+			std::string arg;
+			while (ss >> arg)
+			{
+				ParseColorMap(currentLine, ss, prefix, arg, colorMap);
+			}
+
+			// HACK: Should we really have to specify the full path here?
+			colorMap.FileName = (m_MaterialPath.branch_path() / colorMap.FileName).string();
+			currentMaterial->SpecularMap = colorMap;
+			continue;
+		}
+		// Normal map (bump map)
+		if (prefix == "bump")
+		{
+			MaterialInfo::BumpMap bumpMap;
+
+			std::string fileName;
+			std::string arg;
+			while (ss >> arg)
+			{
+				ParseBumpMap(currentLine, ss, prefix, arg, bumpMap);
+			}
+
+			// HACK: Should we really have to specify the full path here?
+			bumpMap.FileName = (m_MaterialPath.branch_path() / bumpMap.FileName).string();
+			currentMaterial->NormalMap = bumpMap;
 			continue;
 		}
 	}
 }
+
+void OBJ::ParseTextureMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::TextureMap &textureMap)
+{
+	if (arg == "-blendu")
+	{
+		std::string val;
+		ss >> val;
+		if (val == "off")
+			textureMap.blendu = false;
+		else if (val == "on")
+			textureMap.blendu = true;
+		else
+			LOG_ERROR("Unrecognized MTL value \"%s\" to argument \"%s %s\" on line %i", val.c_str(), prefix.c_str(), arg.c_str(), line);
+	}
+	else if (arg == "-blendv")
+	{
+		std::string val;
+		ss >> val;
+		if (val == "off")
+			textureMap.blendv = false;
+		else if (val == "on")
+			textureMap.blendv = true;
+		else
+			LOG_ERROR("Unrecognized MTL value \"%s\" to argument \"%s %s\" on line %i", val.c_str(), prefix.c_str(), arg.c_str(), line);
+	}
+	else if (arg == "-clamp")
+	{
+		std::string val;
+		ss >> val;
+		if (val == "off")
+			textureMap.clamp = false;
+		else if (val == "on")
+			textureMap.clamp = true;
+		else
+			LOG_ERROR("Unrecognized MTL value \"%s\" to argument \"%s %s\" on line %i", val.c_str(), prefix.c_str(), arg.c_str(), line);
+	}
+	else if (arg == "-o")
+	{
+		float u, v, w;
+		if (ss >> u >> v >> w)
+		{
+			textureMap.o = std::make_tuple(u, v, w);
+		}
+		else
+		{
+			LOG_ERROR("Unrecognized MTL value to argument \"%s %s\" on line %i", prefix.c_str(), arg.c_str(), line);
+		}
+	}
+	else if (arg == "-s")
+	{
+		float u, v, w;
+		if (ss >> u >> v >> w)
+		{
+			textureMap.s = std::make_tuple(u, v, w);
+		}
+		else
+		{
+			LOG_ERROR("Unrecognized MTL value to argument \"%s %s\" on line %i", prefix.c_str(), arg.c_str(), line);
+		}
+	}
+	// Assume unrecognized options is part of the file name
+	else
+	{
+		if (!textureMap.FileName.empty())
+			textureMap.FileName += " ";
+		textureMap.FileName += arg;
+	}
+}
+
+void OBJ::ParseColorMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::ColorMap &colorMap)
+{
+	if (arg == "-cc")
+	{
+		if (prefix != "map_Kd" || prefix != "map_Ks")
+		{
+			LOG_ERROR("Invalid MTL argument \"%s\" to option \"%s\" on line %i", arg.c_str(), prefix.c_str(), line);
+			return;
+		}
+
+		std::string val;
+		if (ss >> val)
+		{
+			if (val == "off")
+				colorMap.cc = false;
+			else if (val == "on")
+				colorMap.cc = true;
+			else
+				LOG_ERROR("Unrecognized MTL value \"%s\" to argument \"%s %s\" on line %i", val.c_str(), prefix.c_str(), arg.c_str(), line);
+		}
+		else
+		{
+			LOG_ERROR("Unrecognized MTL value to argument \"%s %s\" on line %i", prefix.c_str(), arg.c_str(), line);
+		}
+	}
+	else
+	{
+		ParseTextureMap(line, ss, prefix, arg, colorMap);
+	}
+}
+
+void OBJ::ParseBumpMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::BumpMap &bumpMap)
+{
+	if (arg == "-bm")
+	{
+		if (prefix != "bump")
+		{
+			LOG_ERROR("Invalid MTL argument \"%s\" to option \"%s\" on line %i", arg.c_str(), prefix.c_str(), line);
+			return;
+		}
+
+		float val;
+		if (ss >> val)
+			bumpMap.bm = val;
+		else
+			LOG_ERROR("Unrecognized MTL value to argument \"%s %s\" on line %i", prefix.c_str(), arg.c_str(), line);
+	}
+	else
+	{
+		ParseTextureMap(line, ss, prefix, arg, bumpMap);
+	}
+}

src/OBJ.h

@@ -10,21 +10,78 @@
 #include <map>
 
 #include <boost/filesystem/path.hpp>
+#include <boost/program_options.hpp>
 
 class OBJ
 {
 public:
 	struct MaterialInfo
 	{
-		std::string TextureFile;
+		struct TextureMap
-		std::tuple<float, float, float> AmbientColor;
+		{
-		std::tuple<float, float, float> DiffuseColor;
+			TextureMap()
-		std::tuple<float, float, float> SpecularColor;
+				: blendu(true)
-		std::tuple<float, float, float> TransmissionFilter;
+				, blendv(true)
-		float OpticalDensity;
+				, clamp(false)
-		float Alpha;
+				, o(std::make_tuple(0.f, 0.f, 0.f))
-		float Shininess;
+				, s(std::make_tuple(1.f, 1.f, 1.f)) { }
-		int IlluminationModel;
+
+			std::string FileName;
+
+			// http://paulbourke.net/dataformats/mtl/
+			// "These options are described in detail in 'Options for texture map statements' on page 5-18."
+
+			// Horizontal texture blending
+			bool blendu; // = true
+			// Vertical texture blending
+			bool blendv; // = true
+			// Clamping
+			bool clamp; // = false
+			// Offset
+			std::tuple<float, float, float> o; // = (0, 0, 0)
+			// Scale
+			std::tuple<float, float, float> s; // = (1, 1, 1)
+		};
+
+		struct ColorMap : public TextureMap
+		{
+			ColorMap()
+				: cc(false) { }
+
+			// Color correction
+			bool cc; // = false
+		};
+
+		struct BumpMap : public TextureMap
+		{
+			BumpMap()
+				: bm(1.f) { }
+
+			// Bump multiplier
+			float bm; // = 1?
+		};
+
+		MaterialInfo()
+			: AmbientColor(std::make_tuple(0.2f, 0.2f, 0.2f))
+			, DiffuseColor(std::make_tuple(0.8f, 0.8f, 0.8f))
+			, SpecularColor(std::make_tuple(1.0f, 1.0f, 1.0f))
+			, TransmissionFilter(std::make_tuple(1.0f, 1.0f, 1.0f))
+			, OpticalDensity(1.0f)
+			, Alpha(1.0f)
+			, Shininess(0.0f)
+			, IlluminationModel(0) { }
+
+		ColorMap DiffuseTexture;
+		ColorMap SpecularMap;
+		BumpMap NormalMap;
+		std::tuple<float, float, float> AmbientColor; // = (0.2, 0.2, 0.2)
+		std::tuple<float, float, float> DiffuseColor; // = (0.8, 0.8, 0.8)
+		std::tuple<float, float, float> SpecularColor; // = (1, 1, 1)
+		std::tuple<float, float, float> TransmissionFilter; // = (1, 1, 1)
+		float OpticalDensity; // = 1
+		float Alpha; // = 1
+		float Shininess; // = 0
+		int IlluminationModel; // = 0
 	};
 
 	struct FaceDefinition
@@ -59,6 +116,9 @@ private:
 	MaterialInfo* m_CurrentMaterial;
 
 	void ParseMaterial();
+	void ParseTextureMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::TextureMap &textureMap);
+	void ParseColorMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::ColorMap &textureMap);
+	void ParseBumpMap(unsigned int line, std::stringstream &ss, std::string prefix, std::string arg, MaterialInfo::BumpMap &textureMap);
 };
 
 #endif // OBJ_h__