source/light.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2007  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "except.h"
   9 #include "light.h"
  10 #include "misc.h"
  11
  12 using namespace std;
  13
  14 namespace Msp {
  15 namespace GL {
  16
  17 Light::Light():
  18         ambient(0),
  19         diffuse(1),
  20         specular(1),
  21         position(0, 0, 1, 0),
  22         spot_dir(0, 0, -1),
  23         spot_exp(0),
  24         spot_cutoff(180)
  25 {
  26         attenuation[0] = 1;
  27         attenuation[1] = 0;
  28         attenuation[2] = 0;
  29 }
  30
  31 void Light::set_ambient(const Color &c)
  32 {
  33         ambient = c;
  34 }
  35
  36 void Light::set_diffuse(const Color &c)
  37 {
  38         diffuse = c;
  39 }
  40
  41 void Light::set_specular(const Color &c)
  42 {
  43         specular = c;
  44 }
  45
  46 void Light::set_position(const Vector4 &p)
  47 {
  48         position = p;
  49 }
  50
  51 void Light::set_spot_direction(const Vector3 &d)
  52 {
  53         spot_dir = d;
  54 }
  55
  56 void Light::set_spot_exponent(float e)
  57 {
  58         spot_exp = e;
  59 }
  60
  61 void Light::set_spot_cutoff(float c)
  62 {
  63         spot_cutoff = c;
  64 }
  65
  66 void Light::set_attenuation(float c, float l, float q)
  67 {
  68         attenuation[0] = c;
  69         attenuation[1] = l;
  70         attenuation[2] = q;
  71 }
  72
  73 void Light::bind() const
  74 {
  75         if(current_lights[current_unit]!=this)
  76         {
  77                 GLenum l = GL_LIGHT0+current_unit;
  78                 enable(l);
  79                 glLightfv(l, GL_AMBIENT, &ambient.r);
  80                 glLightfv(l, GL_DIFFUSE, &diffuse.r);
  81                 glLightfv(l, GL_SPECULAR, &specular.r);
  82                 glLightfv(l, GL_POSITION, &position.x);
  83                 glLightfv(l, GL_SPOT_DIRECTION, &spot_dir.x);
  84                 glLightf(l, GL_SPOT_EXPONENT, spot_exp);
  85                 glLightf(l, GL_SPOT_CUTOFF, spot_cutoff);
  86                 glLightf(l, GL_CONSTANT_ATTENUATION, attenuation[0]);
  87                 glLightf(l, GL_LINEAR_ATTENUATION, attenuation[1]);
  88                 glLightf(l, GL_QUADRATIC_ATTENUATION, attenuation[2]);
  89                 current_lights[current_unit] = this;
  90         }
  91 }
  92
  93 void Light::bind_to(unsigned i) const
  94 {
  95         activate(i);
  96         bind();
  97 }
  98
  99 void Light::activate(unsigned i)
 100 {
 101         static unsigned max_lights = get_i(GL_MAX_LIGHTS);
 102
 103         if(i>=max_lights)
 104                 throw InvalidParameterValue("Light unit index out of range");
 105
 106         if(i>=current_lights.size())
 107                 current_lights.resize(i+1);
 108
 109         current_unit = i;
 110 }
 111
 112 void Light::unbind()
 113 {
 114         if(current_lights[current_unit])
 115         {
 116                 disable(GL_LIGHT0+current_unit);
 117                 current_lights[current_unit] = 0;
 118         }
 119 }
 120
 121 void Light::unbind_from(unsigned i)
 122 {
 123         activate(i);
 124         unbind();
 125 }
 126
 127 unsigned Light::current_unit = 0;
 128 vector<const Light *> Light::current_lights(1);
 129
 130 } // namespace GL
 131 } // namespace Msp