source/lighting.cpp

   1 #include <stdexcept>
   2 #include <cmath>
   3 #include <msp/gl/extensions/msp_legacy_features.h>
   4 #include "error.h"
   5 #include "light.h"
   6 #include "lighting.h"
   7 #include "lightunit.h"
   8 #include "matrix.h"
   9 #include "misc.h"
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace GL {
  15
  16 Lighting::Lighting():
  17         ambient(0.2),
  18         zenith_direction(0, 0, 1),
  19         horizon_angle(Geometry::Angle<float>::zero()),
  20         fog_color(0.0f, 0.0f, 0.0f, 0.0f),
  21         fog_density(0.0f)
  22 { }
  23
  24 void Lighting::set_ambient(const Color &a)
  25 {
  26         ambient = a;
  27 }
  28
  29 void Lighting::set_sky_color(const Color &s)
  30 {
  31         sky_color = s;
  32 }
  33
  34 void Lighting::set_zenith_direction(const Vector3 &d)
  35 {
  36         zenith_direction = d;
  37 }
  38
  39 void Lighting::set_horizon_angle(const Geometry::Angle<float> &a)
  40 {
  41         horizon_angle = a;
  42 }
  43
  44 void Lighting::set_fog_color(const Color &c)
  45 {
  46         fog_color = c;
  47 }
  48
  49 void Lighting::set_fog_density(float d)
  50 {
  51         if(d<0)
  52                 throw invalid_argument("Lighting::set_fog_density");
  53
  54         fog_density = d;
  55 }
  56
  57 void Lighting::set_fog_half_distance(float d)
  58 {
  59         set_fog_density(-log(pow(0.5, 1.0/d)));
  60 }
  61
  62 void Lighting::attach(unsigned i, const Light &l)
  63 {
  64         if(i>=lights.size())
  65                 lights.resize(i+1);
  66
  67         lights[i] = &l;
  68         if(current()==this)
  69                 l.bind_to(i);
  70 }
  71
  72 void Lighting::detach(unsigned i)
  73 {
  74         if(i>=lights.size())
  75                 return;
  76
  77         lights[i] = 0;
  78         if(current()==this)
  79                 Light::unbind_from(i);
  80 }
  81
  82 const Light *Lighting::get_attached_light(unsigned i) const
  83 {
  84         return i<lights.size() ? lights[i] : 0;
  85 }
  86
  87 void Lighting::update_shader_data(ProgramData &shdata, const Matrix &view_matrix) const
  88 {
  89         shdata.uniform("ambient_color", ambient);
  90         shdata.uniform("sky_color", sky_color);
  91         shdata.uniform("eye_zenith_dir", view_matrix.block<3, 3>(0, 0)*zenith_direction);
  92         shdata.uniform("horizon_limit", horizon_angle.radians());
  93         shdata.uniform("fog_color", fog_color);
  94         shdata.uniform("fog_density", fog_density);
  95
  96         // For backwards compatibility
  97         shdata.uniform("eye_sky_dir", view_matrix.block<3, 3>(0, 0)*zenith_direction);
  98
  99         for(unsigned i=0; i<lights.size(); ++i)
 100                 if(lights[i])
 101                         lights[i]->update_shader_data(shdata, view_matrix, i);
 102 }
 103
 104 void Lighting::bind() const
 105 {
 106         static Require _req(MSP_legacy_features);
 107         if(lights.size()>LightUnit::get_n_units())
 108                 throw invalid_operation("Lighting::bind");
 109
 110         const Lighting *old = current();
 111         if(!set_current(this))
 112                 return;
 113
 114         enable(GL_LIGHTING);
 115         glLightModelfv(GL_LIGHT_MODEL_AMBIENT, &ambient.r);
 116         for(unsigned i=0; i<lights.size(); ++i)
 117         {
 118                 if(lights[i])
 119                         lights[i]->bind_to(i);
 120                 else
 121                         Light::unbind_from(i);
 122         }
 123
 124         if(old)
 125         {
 126                 for(unsigned i=lights.size(); i<old->lights.size(); ++i)
 127                         Light::unbind_from(i);
 128         }
 129
 130         if(fog_density)
 131         {
 132                 enable(GL_FOG);
 133                 glFogi(GL_FOG_MODE, GL_EXP);
 134                 glFogf(GL_FOG_DENSITY, fog_density);
 135                 glFogfv(GL_FOG_COLOR, &fog_color.r);
 136         }
 137 }
 138
 139 void Lighting::unbind()
 140 {
 141         const Lighting *old = current();
 142         if(!set_current(0))
 143                 return;
 144
 145         for(unsigned i=0; i<old->lights.size(); ++i)
 146                 if(old->lights[i])
 147                         Light::unbind_from(i);
 148
 149         disable(GL_LIGHTING);
 150         if(old->fog_density)
 151                 disable(GL_FOG);
 152 }
 153
 154 } // namespace GL
 155 } // namespace Msp