source/graphics/LightEnv.h

   1 /* Copyright (C) 2021 Wildfire Games.
   2  * This file is part of 0 A.D.
   3  *
   4  * 0 A.D. is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * 0 A.D. is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * CLightEnv, a class describing the current lights
  20  */
  21
  22 #ifndef INCLUDED_LIGHTENV
  23 #define INCLUDED_LIGHTENV
  24
  25 #include "graphics/Color.h"
  26 #include "maths/MathUtil.h"
  27 #include "maths/Vector3D.h"
  28
  29 class CMapWriter;
  30 class CMapReader;
  31
  32 /**
  33  * Class CLightEnv: description of a lighting environment - contains all the
  34  * necessary parameters for representation of the lighting within a scenario
  35  */
  36 class CLightEnv
  37 {
  38 public:
  39         RGBColor m_SunColor;
  40         RGBColor m_AmbientColor;
  41         RGBColor m_FogColor;
  42
  43         float m_FogFactor;
  44         float m_FogMax;
  45
  46         float m_Brightness, m_Contrast, m_Saturation, m_Bloom;
  47
  48         CLightEnv();
  49
  50         float GetElevation() const { return m_Elevation; }
  51         float GetRotation() const { return m_Rotation; }
  52         const CVector3D& GetSunDir() const { return m_SunDir; }
  53
  54         void SetElevation(float f);
  55         void SetRotation(float f);
  56
  57         /**
  58          * Calculate brightness of a point of a unit with the given normal vector,
  59          * for rendering with CPU lighting.
  60          * The resulting color contains both ambient and diffuse light.
  61          * To cope with sun overbrightness, the color is scaled by 0.5.
  62          *
  63          * @param normal normal vector (must have length 1)
  64          */
  65         RGBColor EvaluateUnitScaled(const CVector3D& normal) const
  66         {
  67                 float dot = -normal.Dot(m_SunDir);
  68
  69                 RGBColor color = m_AmbientColor;
  70                 if (dot > 0)
  71                         color += m_SunColor * dot;
  72
  73                 return color * 0.5f;
  74         }
  75
  76         // Comparison operators
  77         bool operator==(const CLightEnv& o) const
  78         {
  79                 return m_Elevation == o.m_Elevation &&
  80                         m_Rotation == o.m_Rotation &&
  81                         m_SunColor == o.m_SunColor &&
  82                         m_AmbientColor == o.m_AmbientColor &&
  83                         m_FogColor == o.m_FogColor &&
  84                         m_FogFactor == o.m_FogFactor &&
  85                         m_FogMax == o.m_FogMax &&
  86                         m_Brightness == o.m_Brightness &&
  87                         m_Contrast == o.m_Contrast &&
  88                         m_Saturation == o.m_Saturation &&
  89                         m_Bloom == o.m_Bloom;
  90         }
  91
  92         bool operator!=(const CLightEnv& o) const
  93         {
  94                 return !(*this == o);
  95         }
  96
  97 private:
  98         friend class CMapWriter;
  99         friend class CMapReader;
 100         friend class CXMLReader;
 101
 102         /**
 103         * Height of sun above the horizon, in radians.
 104         * For example, an elevation of M_PI/2 means the sun is straight up.
 105         */
 106         float m_Elevation;
 107
 108         /**
 109         * Direction of sun on the compass, in radians.
 110         * For example, a rotation of zero means the sun is in the direction (0,0,-1)
 111         * and a rotation of M_PI/2 means the sun is in the direction (1,0,0) (not taking
 112         * elevation into account).
 113         */
 114         float m_Rotation;
 115
 116         /**
 117         * Vector corresponding to m_Elevation and m_Rotation.
 118         * Updated by CalculateSunDirection.
 119         */
 120         CVector3D m_SunDir;
 121
 122         void CalculateSunDirection();
 123 };
 124
 125 #endif // INCLUDED_LIGHTENV