source/texturing.cpp

   1 #include <msp/core/hash.h>
   2 #include "texture.h"
   3 #include "texturing.h"
   4 #include "texunit.h"
   5
   6 using namespace std;
   7
   8 namespace Msp {
   9 namespace GL {
  10
  11 Texturing::~Texturing()
  12 {
  13         if(current()==this)
  14                 unbind();
  15 }
  16
  17 int Texturing::find_free_unit(const string &name_hint) const
  18 {
  19         unsigned max_unit = TexUnit::get_n_units();
  20         // Leave some space for effect textures
  21         max_unit -= min(max_unit/4, 8U);
  22         unsigned initial_unit = (name_hint.empty() ? 0 : hash32(name_hint)%max_unit);
  23         unsigned unit = initial_unit;
  24         while(get_attached_texture(unit))
  25         {
  26                 unit = (unit+1)%max_unit;
  27                 if(unit==initial_unit)
  28                         return -1;
  29         }
  30
  31         return unit;
  32 }
  33
  34 void Texturing::attach(unsigned attch, const Texture &tex)
  35 {
  36         set_attachment(attch, &tex);
  37 }
  38
  39 void Texturing::detach(unsigned attch)
  40 {
  41         set_attachment(attch, 0);
  42 }
  43
  44 void Texturing::set_attachment(unsigned unit, const Texture *tex)
  45 {
  46         if(unit>=TexUnit::get_n_units())
  47                 throw out_of_range("Texturing::set_attachment");
  48
  49         if(tex)
  50         {
  51                 vector<Attachment>::iterator i;
  52                 for(i=attachments.begin(); (i!=attachments.end() && i->unit<=unit); ++i)
  53                         if(i->unit==unit)
  54                         {
  55                                 i->texture = tex;
  56                                 if(current()==this)
  57                                         tex->bind_to(unit);
  58                                 return;
  59                         }
  60
  61                 attachments.insert(i, Attachment(unit, tex));
  62                 if(current()==this)
  63                         tex->bind_to(unit);
  64         }
  65         else
  66         {
  67                 for(vector<Attachment>::iterator i=attachments.begin(); (i!=attachments.end() && i->unit<=unit); ++i)
  68                         if(i->unit==unit)
  69                         {
  70                                 attachments.erase(i);
  71                                 if(current()==this)
  72                                         Texture::unbind_from(unit);
  73                                 return;
  74                         }
  75         }
  76 }
  77
  78 const Texture *Texturing::get_attached_texture(unsigned unit) const
  79 {
  80         for(vector<Attachment>::const_iterator i=attachments.begin(); (i!=attachments.end() && i->unit<=unit); ++i)
  81                 if(i->unit==unit)
  82                         return i->texture;
  83         return 0;
  84 }
  85
  86 void Texturing::bind() const
  87 {
  88         const Texturing *old = current();
  89         if(set_current(this))
  90         {
  91                 if(old)
  92                 {
  93                         vector<Attachment>::const_iterator i = attachments.begin();
  94                         vector<Attachment>::const_iterator j = old->attachments.begin();
  95                         while(i!=attachments.end() || j!=old->attachments.end())
  96                         {
  97                                 if(i!=attachments.end() && (j==old->attachments.end() || i->unit<=j->unit))
  98                                 {
  99                                         i->texture->bind_to(i->unit);
 100                                         if(j!=old->attachments.end() && j->unit==i->unit)
 101                                                 ++j;
 102                                         ++i;
 103                                 }
 104                                 else
 105                                 {
 106                                         Texture::unbind_from(j->unit);
 107                                         ++j;
 108                                 }
 109                         }
 110                 }
 111                 else
 112                 {
 113                         for(vector<Attachment>::const_iterator i=attachments.begin(); i!=attachments.end(); ++i)
 114                                 i->texture->bind_to(i->unit);
 115                 }
 116         }
 117 }
 118
 119 void Texturing::unbind()
 120 {
 121         const Texturing *old = current();
 122         if(set_current(0))
 123         {
 124                 for(vector<Attachment>::const_iterator i=old->attachments.begin(); i!=old->attachments.end(); ++i)
 125                         Texture::unbind_from(i->unit);
 126         }
 127 }
 128
 129
 130 Texturing::Attachment::Attachment(unsigned u, const Texture *t):
 131         unit(u),
 132         texture(t)
 133 { }
 134
 135 } // namespace GL
 136 } // namespace Msp;