TextNodeGLCompat.cc

/*===========================================================================*\
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//=============================================================================
//
//  CLASS TextNode - IMPLEMENTATION
//
//=============================================================================



//== INCLUDES =================================================================

#include <ACG/GL/acg_glew.hh>

#include "TextNode.hh"
#include "../Utils/ImageConversion.hh"


//== NAMESPACES ===============================================================

namespace ACG {
namespace SceneGraph {


//== IMPLEMENTATION ==========================================================

void
TextNode::
enterCompat(GLState& _state, const DrawModes::DrawMode& /*_drawmode*/) {
  if (text_.empty())
    return;

  // store current gl state
  cullFaceEnabled_ = glIsEnabled(GL_CULL_FACE);
  texture2dEnabled_ = glIsEnabled(GL_TEXTURE_2D);
  blendEnabled_ = glIsEnabled(GL_BLEND);
  depthEnabled_ = glIsEnabled(GL_DEPTH_TEST);
  //alphaTest_ = glIsEnabled(GL_ALPHA_TEST);
  if (alphaTest_)
    ACG::GLState::getAlphaFunc(&alphaTestFunc_, &alphaTestValue_);

  glGetIntegerv(GL_BLEND_SRC, &blendSrc_);
  glGetIntegerv(GL_BLEND_DST, &blendDest_);

  // set texture and drawing states
  ACG::GLState::disable(GL_CULL_FACE);
  ACG::GLState::enable(GL_TEXTURE_2D);
  ACG::GLState::enable(GL_BLEND);
  ACG::GLState::enable(GL_ALPHA_TEST);
  ACG::GLState::alphaFunc(GL_GREATER, 0.2f);
  ACG::GLState::blendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  if (alwaysOnTop_)
    ACG::GLState::disable(GL_DEPTH_TEST);
}



//----------------------------------------------------------------------------


void
TextNode::
leaveCompat(GLState& /*_state*/, const DrawModes::DrawMode& /*_drawmode*/) {
  if (text_.empty())
      return;

  // restore the GLState as it was when entering TextNode
  if (cullFaceEnabled_)
    ACG::GLState::enable(GL_CULL_FACE);
  if (!texture2dEnabled_)
    ACG::GLState::disable(GL_TEXTURE_2D);
  if (!blendEnabled_)
    ACG::GLState::disable(GL_BLEND);
  if (depthEnabled_)
    ACG::GLState::enable(GL_DEPTH_TEST);
  else
    ACG::GLState::disable(GL_DEPTH_TEST);
  if (!alphaTest_)
    ACG::GLState::disable(GL_ALPHA_TEST);
  else
    ACG::GLState::alphaFunc(alphaTestFunc_, alphaTestValue_);

  ACG::GLState::blendFunc(blendSrc_, blendDest_);
}

//=============================================================================
} // namespace SceneGraph
} // namespace ACG
//=============================================================================