source/clipping.cpp

   1 #include <msp/gl/extensions/msp_clipping.h>
   2 #include "clipping.h"
   3 #include "clipplane.h"
   4 #include "matrix.h"
   5 #include "misc.h"
   6
   7 using namespace std;
   8
   9 namespace Msp {
  10 namespace GL {
  11
  12 unsigned Clipping::get_n_attach_points()
  13 {
  14         static Require _req(MSP_clipping);
  15         static int count = get_i(GL_MAX_CLIP_PLANES);
  16         return count;
  17 }
  18
  19 void Clipping::attach(unsigned i, const ClipPlane &p)
  20 {
  21         if(i>=get_n_attach_points())
  22                 throw out_of_range("Clipping::attach");
  23
  24         if(i>=planes.size())
  25                 planes.resize(i+1);
  26
  27         planes[i] = &p;
  28         if(current()==this)
  29                 glEnable(GL_CLIP_PLANE0+i);
  30 }
  31
  32 void Clipping::detach(unsigned i)
  33 {
  34         if(i>=planes.size())
  35                 return;
  36
  37         planes[i] = 0;
  38         if(current()==this)
  39                 disable(GL_CLIP_PLANE0+i);
  40 }
  41
  42 void Clipping::update_shader_data(ProgramData &shdata, const Matrix &view_matrix) const
  43 {
  44         Matrix view_inverse = invert(view_matrix);
  45         for(unsigned i=0; i<planes.size(); ++i)
  46                 if(planes[i])
  47                         planes[i]->update_shader_data(shdata, view_inverse, i);
  48 }
  49
  50 void Clipping::bind() const
  51 {
  52         static Require _req(MSP_clipping);
  53
  54         const Clipping *old = current();
  55         if(!set_current(this))
  56                 return;
  57
  58         for(unsigned i=0; i<planes.size(); ++i)
  59         {
  60                 if(planes[i])
  61                         enable(GL_CLIP_PLANE0+i);
  62                 else
  63                         disable(GL_CLIP_PLANE0+i);
  64         }
  65
  66         if(old)
  67         {
  68                 for(unsigned i=planes.size(); i<old->planes.size(); ++i)
  69                         disable(GL_CLIP_PLANE0+i);
  70         }
  71 }
  72
  73 void Clipping::unbind()
  74 {
  75         const Clipping *old = current();
  76         if(!set_current(0))
  77                 return;
  78
  79         for(unsigned i=0; i<old->planes.size(); ++i)
  80                 if(old->planes[i])
  81                         disable(GL_CLIP_PLANE0+i);
  82 }
  83
  84 } // namespace GL
  85 } // namespace Msp