Adding a stub for the Schlick Fresnel

sources/core/common.h

@@ -5,6 +5,7 @@
 #include <cassert>
 #include <cmath>
 #include <cstring>
+#include <algorithm>
 
 /*! \brief A core implementation of a vector of double.
  *  \ingroup core
@@ -238,6 +239,11 @@ template<typename T> int is_in(std::vector<T> ve, T v)
     return res;
 }
 
+template<typename T> T clamp(T x, T a, T b)
+{
+	return std::max<T>(std::min<T>(x, b), a);
+}
+
 #define NOT_IMPLEMENTED() \
 std::cerr << "<<ERROR>> not implemented " << __FILE__ \
           << ":" << __LINE__ << std::endl; \
@@ -251,4 +257,4 @@ throw
 #define ALTA_DLL_EXPORT extern "C" __declspec(dllexport)
 #else
 #define ALTA_DLL_EXPORT extern "C"
-#endif
\ No newline at end of file
+#endif

sources/plugins/nonlinear_fresnel_schlick/function.cpp

+#include "function.h"
+
+#include <string>
+#include <iostream>
+#include <fstream>
+#include <limits>
+#include <algorithm>
+#include <cmath>
+
+#include <core/common.h>
+
+ALTA_DLL_EXPORT function* provide_function()
+{
+    return new schlick();
+}
+
+// Overload the function operator
+vec schlick::operator()(const vec& x) const 
+{
+	return value(x);
+}
+vec schlick::value(const vec& x) const 
+{
+	vec res(_nY);
+	for(int i=0; i<_nY; ++i)
+	{
+		res[i] = R + (1.0 - R) * pow(1.0 - clamp(x[0], 0.0, 1.0), 5.0);
+	}
+
+	return res;
+}
+
+//! Load function specific files
+void schlick::load(const std::string& filename) 
+{
+    std::cerr << "Cannot load a Schlick file." << std::endl;
+    throw;
+}
+
+//! Number of parameters to this non-linear function
+int schlick::nbParameters() const 
+{
+	return 0;
+}
+
+//! Get the vector of parameters for the function
+vec schlick::parameters() const 
+{
+	vec r(0);
+	return r;
+}
+
+//! Update the vector of parameters for the function
+void schlick::setParameters(const vec& p) 
+{
+}
+
+//! Obtain the derivatives of the function with respect to the 
+//! parameters. 
+vec schlick::parametersJacobian(const vec& x) const 
+{
+	vec r(0);
+	return r;
+}
+
+
+void schlick::bootstrap(const data* d, const arguments& args)
+{
+}

sources/plugins/nonlinear_fresnel_schlick/function.h

+#pragma once
+
+// Include STL
+#include <vector>
+#include <string>
+
+// Interface
+#include <core/function.h>
+#include <core/data.h>
+#include <core/fitter.h>
+#include <core/args.h>
+#include <core/common.h>
+
+
+class schlick : public nonlinear_function
+{
+
+	public: // methods
+
+		// Overload the function operator
+		virtual vec operator()(const vec& x) const ;
+		virtual vec value(const vec& x) const ;
+
+
+		//! \brief Boostrap the function by defining the diffuse term
+		virtual void bootstrap(const data* d, const arguments& args);
+
+		//! \brief Load function specific files
+		virtual void load(const std::string& filename) ;
+
+		//! \brief Number of parameters to this non-linear function
+		virtual int nbParameters() const ;
+
+		//! \brief Get the vector of parameters for the function
+		virtual vec parameters() const ;
+
+		//! \brief Update the vector of parameters for the function
+		virtual void setParameters(const vec& p) ;
+
+		//! \brief Obtain the derivatives of the function with respect to the
+		//! parameters. 
+		virtual vec parametersJacobian(const vec& x) const ;
+
+		//! \brief Provide the dimension of the input space of the function
+		inline virtual int dimX() const
+		{
+			return 1;
+		}
+		inline virtual int dimY() const
+		{
+			return 1;
+		}
+
+		//! \brief Provide the parametrization of the input space of the function.
+		//! For this one, we fix that the parametrization is in THETAD_PHID
+		virtual params::input parametrization() const;
+		virtual void setParametrization(params::input new_param);
+
+	protected: // methods
+
+	private: // data
+
+		//! Unidimensional Fresnel reflectance at theta = 0
+		double R;
+} ;
+

sources/plugins/nonlinear_fresnel_schlick/nonlinear_fresnel_schlick.pro

+TEMPLATE        = lib
+CONFIG         *= plugin
+
+DESTDIR         = ../../build
+
+INCLUDEPATH    += ../..
+HEADERS         = function.h
+SOURCES         = function.cpp
+
+
+LIBS           += -L../../build  \
+						-lcore
+

sources/plugins/nonlinear_levenberg_eigen/fitter.cpp

@@ -54,12 +54,6 @@ struct EigenFunctor: Eigen::DenseFunctor<double>
 			for(int i=0; i<_f->dimY(); ++i)
 				y(i*_d->size() + s) = _y[i];
 
-			/*
-			// Cosine term. It is supposed to improve the quality of the fit (see Ngan '05).
-			vec x2(3);
-			params::convert(&_x[0], _d->input_parametrization(), params::ISOTROPIC_TV_TL_DPHI, &x2[0]);
-			y *= cos(x2[1]);
-			*/
 		}
 #ifdef DEBUG
 		std::cout << "diff vector:" << std::endl << y << std::endl << std::endl ;
@@ -83,12 +77,7 @@ struct EigenFunctor: Eigen::DenseFunctor<double>
 
 			// Get the associated jacobian
 			vec _jac = _f->parametersJacobian(xi);
-		/*	
-			// Cosine term. It is supposed to improve the quality of the fit (see Ngan '05).
-			vec x2(3);
-			params::convert(&xi[0], _d->input_parametrization(), params::ISOTROPIC_TV_TL_DPHI, &x2[0]);
-			_jac = _jac * cos(x2[1]);
-		*/
+			
 			// Fill the columns of the matrix
 #ifdef DEBUG
 			Eigen::MatrixXd temp (_f->dimY(), _f->nbParameters());

sources/plugins/plugins.pro

 TEMPLATE = subdirs
 
 SUBDIRS  = \
-				rational_fitter_cgal          \
-				rational_fitter_quadprog      \
-#				rational_fitter_parallel      \
-				rational_fitter_eigen         \
-				rational_fitter_leastsquare   \
-				rational_function_chebychev   \
-				rational_fitter_matlab        \
-#				rational_fitter_dca           \
-				nonlinear_levenberg_eigen     \
-				nonlinear_function_phong      \
-				nonlinear_function_lafortune  \
-				nonlinear_function_isotropic_lafortune  \
-				data_merl                     \
-#			  data_astm
+				rational_fitter_cgal							\
+				rational_fitter_quadprog					\
+#				rational_fitter_parallel					\
+				rational_fitter_eigen						\
+				rational_fitter_leastsquare				\	
+				rational_function_chebychev				\
+				rational_fitter_matlab						\
+#				rational_fitter_dca							\
+				nonlinear_levenberg_eigen					\
+				nonlinear_fresnel_schlick					\
+				nonlinear_function_phong					\
+				nonlinear_function_lafortune				\
+				nonlinear_function_isotropic_lafortune	\
+				data_merl										\
+#				data_astm