source/clipplane.cpp

   1 #include <msp/gl/extensions/msp_clipping.h>
   2 #include <msp/gl/extensions/msp_legacy_features.h>
   3 #include <msp/strings/format.h>
   4 #include "clipplane.h"
   5 #include "clipunit.h"
   6 #include "gl.h"
   7 #include "matrix.h"
   8 #include "misc.h"
   9 #include "programdata.h"
  10
  11 namespace Msp {
  12 namespace GL {
  13
  14 ClipPlane::ClipPlane():
  15         eq(0, 0, 0, 1)
  16 { }
  17
  18 ClipPlane::ClipPlane(const Vector4 &e):
  19         eq(e)
  20 { }
  21
  22 ClipPlane::ClipPlane(const Vector3 &p, const Vector3 &d):
  23         eq(compose(d, -dot(p, d)))
  24 { }
  25
  26 void ClipPlane::update(unsigned index) const
  27 {
  28         double deq[4];
  29         for(unsigned i=0; i<4; ++i)
  30                 deq[i] = eq[i];
  31         glClipPlane(GL_CLIP_PLANE0+index, deq);
  32 }
  33
  34 void ClipPlane::set_equation(const Vector4 &e)
  35 {
  36         eq = e;
  37         if(ClipUnit *unit = ClipUnit::find_unit(this))
  38                 update(unit->get_index());
  39 }
  40
  41 void ClipPlane::set_plane(const Vector3 &p, const Vector3 &d)
  42 {
  43         Vector3 nd = normalize(d);
  44         set_equation(compose(nd, -dot(p, nd)));
  45 }
  46
  47 void ClipPlane::update_shader_data(ProgramData &shdata, const Matrix &view_inverse, unsigned i) const
  48 {
  49         shdata.uniform(format("clip_planes[%d].equation", i), eq*view_inverse);
  50 }
  51
  52 void ClipPlane::bind_to(unsigned i) const
  53 {
  54         Require _req(MSP_clipping);
  55         Require _req2(MSP_legacy_features);
  56
  57         ClipUnit &unit = ClipUnit::get_unit(i);
  58         if(unit.set_plane(this))
  59         {
  60                 enable(GL_CLIP_PLANE0+unit.get_index());
  61                 update(unit.get_index());
  62         }
  63 }
  64
  65 void ClipPlane::unbind_from(unsigned i)
  66 {
  67         ClipUnit &unit = ClipUnit::get_unit(i);
  68         if(unit.set_plane(0))
  69                 disable(GL_CLIP_PLANE0+unit.get_index());
  70 }
  71
  72 } // namespace GL
  73 } // namespace Msp