/*
 * Filters.cpp
 *
 *  Created on: Jun 18, 2008
 *      Author: pete
 */
#include "Common.hpp"

#ifdef USE_GLES1
#include <GLES/gl.h>
#else
#ifdef __APPLE__
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#else
#include <GL/gl.h>
#include <GL/glu.h>
#endif
#endif

#include "Filters.hpp"


void
Brighten::Draw(RenderContext &context)
{
  float points[4][2] = {{-0.5, -0.5},
                        {-0.5,  0.5},
                        { 0.5,  0.5},
                        { 0.5,  -0.5}};

  glEnableClientState(GL_VERTEX_ARRAY);
  glVertexPointer(2,GL_FLOAT,0,points);

  glColor4f(1.0, 1.0, 1.0, 1.0);
  glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_ZERO, GL_DST_COLOR);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  glDisableClientState(GL_VERTEX_ARRAY);
}

void
Darken::Draw(RenderContext &context)
{
  float points[4][2] = {{-0.5, -0.5},
                        {-0.5,  0.5},
                        { 0.5,  0.5},
                        { 0.5,  -0.5}};

  glEnableClientState(GL_VERTEX_ARRAY);
  glVertexPointer(2,GL_FLOAT,0,points);
  glColor4f(1.0, 1.0, 1.0, 1.0);
  glBlendFunc(GL_ZERO, GL_DST_COLOR);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
  glDisableClientState(GL_VERTEX_ARRAY);
}

void
Invert::Draw(RenderContext &context)
{
  float points[4][2] = {{-0.5, -0.5},
                        {-0.5,  0.5},
                        { 0.5,  0.5},
                        { 0.5,  -0.5}};

  glEnableClientState(GL_VERTEX_ARRAY);
  glVertexPointer(2,GL_FLOAT,0,points);
  glColor4f(1.0, 1.0, 1.0, 1.0);
  glBlendFunc(GL_ONE_MINUS_DST_COLOR, GL_ZERO);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  glDisableClientState(GL_VERTEX_ARRAY);
}

void
Solarize::Draw(RenderContext &context)
{
  float points[4][2] = {{-0.5, -0.5},
                        {-0.5,  0.5},
                        { 0.5,  0.5},
                        { 0.5,  -0.5}};

  glEnableClientState(GL_VERTEX_ARRAY);
  glVertexPointer(2,GL_FLOAT,0,points);

  glColor4f(1.0, 1.0, 1.0, 1.0);
  glBlendFunc(GL_ZERO, GL_ONE_MINUS_DST_COLOR);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_DST_COLOR, GL_ONE);
  glDrawArrays(GL_TRIANGLE_FAN,0,4);
  glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

  glDisableClientState(GL_VERTEX_ARRAY);
}