nevrax.org : docs

00001 
+00007 /* Copyright, 2001 Nevrax Ltd.
+00008  *
+00009  * This file is part of NEVRAX NEL.
+00010  * NEVRAX NEL is free software; you can redistribute it and/or modify
+00011  * it under the terms of the GNU General Public License as published by
+00012  * the Free Software Foundation; either version 2, or (at your option)
+00013  * any later version.
+00014 
+00015  * NEVRAX NEL is distributed in the hope that it will be useful, but
+00016  * WITHOUT ANY WARRANTY; without even the implied warranty of
+00017  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+00018  * General Public License for more details.
+00019 
+00020  * You should have received a copy of the GNU General Public License
+00021  * along with NEVRAX NEL; see the file COPYING. If not, write to the
+00022  * Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+00023  * MA 02111-1307, USA.
+00024  */
+00025 
+00026 #include "std3d.h"
+00027 
+00028 #include "3d/light.h"
+00029 
+00030 using namespace NLMISC;
+00031 
+00032 namespace NL3D 
+00033 {
+00034 
+00035 // ***************************************************************************
+00036 
+00037 void CLight::setupDirectional (const CRGBA& ambiant, const CRGBA& diffuse, const CRGBA& specular, const CVector& direction,
+00038                                                            float constant, float linear, float quadratic)
+00039 {
+00040         // Set the mode
+00041         setMode (DirectionalLight);
+00042 
+00043         // Set the colors
+00044         setAmbiant (ambiant);
+00045         setDiffuse (diffuse);
+00046         setSpecular (specular);
+00047 
+00048         // Set the direction
+00049         setDirection (direction);
+00050 
+00051         // Set attenuation
+00052         setConstantAttenuation (constant);
+00053         setLinearAttenuation (linear);
+00054         setQuadraticAttenuation (quadratic);
+00055 }
+00056         
+00057 // ***************************************************************************
+00058 
+00059 void CLight::setupPointLight (const CRGBA& ambiant, const CRGBA& diffuse, const CRGBA& specular, const CVector& position, 
+00060                                                 const CVector& direction, float constant, float linear, float quadratic)
+00061 {
+00062         // Set the mode
+00063         setMode (PointLight);
+00064 
+00065         // Set the colors
+00066         setAmbiant (ambiant);
+00067         setDiffuse (diffuse);
+00068         setSpecular (specular);
+00069 
+00070         // Set the position and direction
+00071         setPosition (position);
+00072         setDirection (direction);
+00073 
+00074         // Set attenuation
+00075         setConstantAttenuation (constant);
+00076         setLinearAttenuation (linear);
+00077         setQuadraticAttenuation (quadratic);
+00078 }
+00079 
+00080 // ***************************************************************************
+00081 
+00082 void CLight::setupSpotLight (const CRGBA& ambiant, const CRGBA& diffuse, const CRGBA& specular, const CVector& position, 
+00083                                                 const CVector& direction, float exponent, float cutoff, float constant, float linear, float quadratic)
+00084 {
+00085         // Set the mode
+00086         setMode (SpotLight);
+00087 
+00088         // Set the colors
+00089         setAmbiant (ambiant);
+00090         setDiffuse (diffuse);
+00091         setSpecular (specular);
+00092 
+00093         // Set the position and direction
+00094         setPosition (position);
+00095         setDirection (direction);
+00096 
+00097         // Set spotlight parameters
+00098         setExponent (exponent);
+00099         setCutoff (cutoff);
+00100 
+00101         // Set attenuation
+00102         setConstantAttenuation (constant);
+00103         setLinearAttenuation (linear);
+00104         setQuadraticAttenuation (quadratic);
+00105 }
+00106 
+00107 // ***************************************************************************
+00108 
+00109 void CLight::setupAttenuation (float farAttenuationBegin, float farAttenuationEnd)
+00110 {
+00111         _ConstantAttenuation=1.f;
+00112         _QuadraticAttenuation=(float)(0.1/(0.9*farAttenuationBegin*farAttenuationBegin));
+00113         _LinearAttenuation=(float)(0.1/(0.9*farAttenuationBegin));
+00114 
+00115         // blend factor
+00116         float factor = (0.1f*_LinearAttenuation*farAttenuationEnd-0.1f*_QuadraticAttenuation*farAttenuationEnd*farAttenuationEnd);
+00117 
+00118         if (factor == 0.0f)
+00119                 factor = 0.0001f;
+00120         factor = (0.9f-0.1f*_QuadraticAttenuation*farAttenuationEnd*farAttenuationEnd)/factor;
+00121 
+00122         if ((factor<0.f)||(factor>1.f))
+00123         {
+00124                 // Better factor
+00125                 float d0_1Lin=1.f / ( _ConstantAttenuation + _LinearAttenuation*farAttenuationEnd );
+00126                 float d0_1Quad=1.f / ( _ConstantAttenuation + _QuadraticAttenuation*farAttenuationEnd*farAttenuationEnd );
+00127 
+00128                 // Better
+00129                 if (fabs (d0_1Lin-0.1f)<fabs (d0_1Quad-0.1f))
+00130                         _QuadraticAttenuation=0.f;
+00131                 else
+00132                         _LinearAttenuation=0.f;
+00133         }
+00134         else
+00135         {
+00136                 _LinearAttenuation*=factor;
+00137                 _QuadraticAttenuation*=(1.f-factor);
+00138         }
+00139 
+00140 #ifdef NL_DEBUG
+00141         // Should be near previous result
+00142         float d1_0=1.f / ( _ConstantAttenuation + _LinearAttenuation*0.f + _QuadraticAttenuation*0.f*0.f );
+00143         float d0_9=1.f / ( _ConstantAttenuation + _LinearAttenuation*farAttenuationBegin + _QuadraticAttenuation*farAttenuationBegin*farAttenuationBegin );
+00144         float d0_1=1.f / ( _ConstantAttenuation + _LinearAttenuation*farAttenuationEnd + _QuadraticAttenuation*farAttenuationEnd*farAttenuationEnd );
+00145 #endif // NL_DEBUG*/
+00146 }
+00147 
+00148 // ***************************************************************************
+00149 
+00150 void CLight::setupSpotExponent (float hotSpotAngle)
+00151 {
+00152         float divid=(float)log (cos (hotSpotAngle));
+00153         if (divid==0.f)
+00154                 divid=0.0001f;
+00155         setExponent ((float)(log (0.9)/divid));
+00156 }
+00157 
+00158 // ***************************************************************************
+00159 
+00160 void CLight::setNoAttenuation ()
+00161 {
+00162         _ConstantAttenuation=1.f;
+00163         _QuadraticAttenuation=0.f;
+00164         _LinearAttenuation=0.f;
+00165 }
+00166 
+00167 // ***************************************************************************
+00168 
+00169 } // NL3D
+
light.cpp
