source/materials/light.cpp

   1 #include <stdexcept>
   2 #include <msp/strings/format.h>
   3 #include "light.h"
   4 #include "matrix.h"
   5 #include "misc.h"
   6 #include "programdata.h"
   7
   8 using namespace std;
   9
  10 namespace Msp {
  11 namespace GL {
  12
  13 Light::Light():
  14         color(1),
  15         transmittance(1),
  16         position(0, 0, 1, 0),
  17         spot_dir(0, 0, -1),
  18         spot_exp(0),
  19         spot_cutoff(Geometry::Angle<float>::straight()),
  20         generation(0)
  21 {
  22         attenuation[0] = 1;
  23         attenuation[1] = 0;
  24         attenuation[2] = 0;
  25 }
  26
  27 void Light::update_matrix()
  28 {
  29         Vector3 up_dir;
  30         if(20*abs(direction.z)>abs(direction.x)+abs(direction.y))
  31                 up_dir.y = 1;
  32         else
  33                 up_dir.z = 1;
  34         Vector3 right_dir = normalize(cross(direction, up_dir));
  35
  36         Vector4 columns[4];
  37         columns[0] = compose(right_dir, 0.0f);
  38         columns[1] = compose(cross(right_dir, direction), 0.0f);
  39         columns[2] = compose(-direction, 0.0f);
  40         columns[3] = position;
  41         matrix = Matrix::from_columns(columns);
  42 }
  43
  44 void Light::set_color(const Color &c)
  45 {
  46         color = c;
  47         ++generation;
  48 }
  49
  50 void Light::set_transmittance(const Color &t)
  51 {
  52         transmittance = t;
  53         ++generation;
  54 }
  55
  56 void Light::set_matrix(const Matrix &m)
  57 {
  58         Placeable::set_matrix(m);
  59         position = matrix.column(3);
  60         spot_dir = normalize(-matrix.column(2).slice<3>(0));
  61         direction = (position.w ? spot_dir : normalize(-position.slice<3>(0)));
  62         update_matrix();
  63         ++generation;
  64 }
  65
  66 void Light::set_position(const Vector4 &p)
  67 {
  68         position = p;
  69         if(!position.w)
  70                 direction = normalize(-position.slice<3>(0));
  71         update_matrix();
  72         ++generation;
  73 }
  74
  75 void Light::set_spot_direction(const Vector3 &d)
  76 {
  77         spot_dir = normalize(d);
  78         if(position.w)
  79                 direction = spot_dir;
  80         update_matrix();
  81         ++generation;
  82 }
  83
  84 void Light::set_spot_exponent(float e)
  85 {
  86         if(e<0)
  87                 throw invalid_argument("Light::set_spot_exponent");
  88
  89         spot_exp = e;
  90         ++generation;
  91 }
  92
  93 void Light::set_spot_cutoff(const Geometry::Angle<float> &c)
  94 {
  95         if(c<Geometry::Angle<float>::zero() || (c>Geometry::Angle<float>::right() && c!=Geometry::Angle<float>::straight()))
  96                 throw invalid_argument("Light::set_spot_cutoff");
  97
  98         spot_cutoff = c;
  99         ++generation;
 100 }
 101
 102 void Light::disable_spot_cutoff()
 103 {
 104         set_spot_cutoff(Geometry::Angle<float>::straight());
 105         ++generation;
 106 }
 107
 108 void Light::set_attenuation(float c, float l, float q)
 109 {
 110         attenuation[0] = c;
 111         attenuation[1] = l;
 112         attenuation[2] = q;
 113         ++generation;
 114 }
 115
 116 void Light::update_shader_data(ProgramData &shdata, unsigned i) const
 117 {
 118         string base = format("light_sources[%d]", i);
 119         shdata.uniform(base+".position", position);
 120         shdata.uniform(base+".color", color.r*transmittance.r, color.g*transmittance.g, color.b*transmittance.b);
 121         shdata.uniform(base+".enabled", 1);
 122 }
 123
 124
 125 Light::Loader::Loader(Light &l):
 126         DataFile::ObjectLoader<Light>(l)
 127 {
 128         add("attenuation", &Loader::attenuation);
 129         add("color", &Loader::color);
 130         add("position", &Loader::position);
 131         add("spot_direction", &Loader::spot_direction);
 132         add("spot_exponent", &Loader::spot_exponent);
 133         add("spot_cutoff", &Loader::spot_cutoff);
 134
 135         // Deprecated
 136         add("diffuse", &Loader::color);
 137         add("specular");
 138 }
 139
 140 void Light::Loader::attenuation(float c, float l, float q)
 141 {
 142         obj.set_attenuation(c, l, q);
 143 }
 144
 145 void Light::Loader::color(float r, float g, float b)
 146 {
 147         obj.set_color(Color(r, g, b));
 148 }
 149
 150 void Light::Loader::position(float x, float y, float z, float w)
 151 {
 152         obj.set_position(Vector4(x, y, z, w));
 153 }
 154
 155 void Light::Loader::spot_direction(float x, float y, float z)
 156 {
 157         obj.set_spot_direction(Vector3(x, y, z));
 158 }
 159
 160 void Light::Loader::spot_exponent(float e)
 161 {
 162         obj.set_spot_exponent(e);
 163 }
 164
 165 void Light::Loader::spot_cutoff(float c)
 166 {
 167         obj.set_spot_cutoff(Geometry::Angle<float>::from_degrees(c));
 168 }
 169
 170 } // namespace GL
 171 } // namespace Msp