PostProcessorGrayPlugin.cc

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#include <ACG/GL/acg_glew.hh>

#include "PostProcessorGrayPlugin.hh"

#include <ACG/GL/ScreenQuad.hh>

#include <OpenFlipper/BasePlugin/PluginFunctions.hh>

PostProcessorGrayscalePlugin::PostProcessorGrayscalePlugin() :
shader_(0)
{
}

PostProcessorGrayscalePlugin::~PostProcessorGrayscalePlugin()
{
  delete shader_;
}


QString PostProcessorGrayscalePlugin::postProcessorName() {
  return QString("Grayscale");
}

QString PostProcessorGrayscalePlugin::checkOpenGL() {
  if (!ACG::openGLVersion(3, 0))
    return QString("Insufficient OpenGL Version! OpenGL 3.0 or higher required");

  return QString("");
}


void PostProcessorGrayscalePlugin::postProcess(ACG::GLState* _glstate, const std::vector<const PostProcessorInput*>& _input, const PostProcessorOutput& _output) {

  // ======================================================================================================
  // Load shader if needed
  // ======================================================================================================
  if (!shader_)
    shader_ = GLSL::loadProgram("Grayscale/screenquad.glsl", "Grayscale/gray.glsl");

  // ======================================================================================================
  // Bind input texture
  // ======================================================================================================

//  glEnable(GL_TEXTURE_2D);
  _input[0]->bindColorTex(0);

  // ======================================================================================================
  // Bind output FBO
  // ======================================================================================================

  _output.bind();

  // ======================================================================================================
  // Setup shader
  // ======================================================================================================

  shader_->use();
  shader_->setUniform("textureSampler", 0);

  ACG::Vec2f texcoordOffset(1.0f / float(_input[0]->width), 1.0f / float(_input[0]->height));
  shader_->setUniform("texcoordOffset", texcoordOffset);

  // ======================================================================================================
  // Execute
  // ======================================================================================================

  ACG::ScreenQuad::draw(shader_);


  shader_->disable();
}