/*
 * GStreamer
 * Copyright (C) 2008 Filippo Argiolas <filippo.argiolas@gmail.com>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include <gstgleffects.h>
#include <gstgleffectscurves.h>

static void gst_gl_effects_luma_to_curve (GstGLEffects *effects,
                                          GstGLEffectsCurve curve,
                                          gint curve_index,
                                          gint width, gint height,
                                          GLuint texture) 
{
  GstGLShader *shader;

  shader = g_hash_table_lookup (effects->shaderstable, "lumamap0");
  
  if (!shader) {
    shader = gst_gl_shader_new ();
    g_hash_table_insert (effects->shaderstable, "lumamap0", shader);
  }

  g_return_if_fail (
    gst_gl_shader_compile_and_check (shader, luma_to_curve_fragment_source,
				     GST_GL_SHADER_FRAGMENT_SOURCE));

  glMatrixMode (GL_PROJECTION);
  glLoadIdentity ();

  gst_gl_shader_use (shader);

  if (effects->curve[curve_index] == 0) {
    /* this parameters are needed to have a right, predictable, mapping */
    glGenTextures(1, &effects->curve[curve_index]); 
    glEnable(GL_TEXTURE_1D); 
    glBindTexture (GL_TEXTURE_1D, effects->curve[curve_index]); 
    glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
    glTexParameteri(GL_TEXTURE_1D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
    glTexParameteri (GL_TEXTURE_1D, GL_TEXTURE_WRAP_S, GL_CLAMP);
    glTexParameteri (GL_TEXTURE_1D, GL_TEXTURE_WRAP_T, GL_CLAMP);
    
    glTexImage1D(GL_TEXTURE_1D, 0, curve.bytes_per_pixel,
                 curve.width, 0,
                 GL_RGB, GL_UNSIGNED_BYTE,
                 curve.pixel_data);
    
    glDisable(GL_TEXTURE_1D);
  }
    
  glActiveTexture (GL_TEXTURE5);
  glEnable (GL_TEXTURE_1D);
  glBindTexture (GL_TEXTURE_1D, effects->curve[curve_index]);

  gst_gl_shader_set_uniform_1i (shader, "curve", 5);

  glDisable (GL_TEXTURE_1D);
  
  gst_gl_effects_draw_texture (effects, texture);
}

static void gst_gl_effects_heat_callback (gint width, gint height, guint texture, gpointer data)
{
    GstGLEffects* effects = GST_GL_EFFECTS (data);
    
    gst_gl_effects_luma_to_curve (effects, heat_curve, GST_GL_EFFECTS_CURVE_HEAT, 
                                  width, height, texture);
}

void
gst_gl_effects_heat (GstGLEffects *effects) {
  GstGLFilter *filter = GST_GL_FILTER (effects);

  gst_gl_filter_render_to_target (filter, effects->intexture, effects->outtexture,
				  gst_gl_effects_heat_callback, effects);
}

static void gst_gl_effects_sepia_callback (gint width, gint height, guint texture, gpointer data)
{
    GstGLEffects* effects = GST_GL_EFFECTS (data);
    
    gst_gl_effects_luma_to_curve (effects, sepia_curve, GST_GL_EFFECTS_CURVE_SEPIA, 
                                  width, height, texture);
}

void
gst_gl_effects_sepia (GstGLEffects *effects) {
  GstGLFilter *filter = GST_GL_FILTER (effects);

  gst_gl_filter_render_to_target (filter, effects->intexture, effects->outtexture,
				  gst_gl_effects_sepia_callback, effects);
}

static void gst_gl_effects_luma_xpro_callback (gint width, gint height, guint texture, gpointer data)
{
    GstGLEffects* effects = GST_GL_EFFECTS (data);
    
    gst_gl_effects_luma_to_curve (effects, luma_xpro_curve, GST_GL_EFFECTS_CURVE_LUMA_XPRO, 
                                  width, height, texture);
}

void
gst_gl_effects_luma_xpro (GstGLEffects *effects) {
  GstGLFilter *filter = GST_GL_FILTER (effects);

  gst_gl_filter_render_to_target (filter, effects->intexture, effects->outtexture,
				  gst_gl_effects_luma_xpro_callback, effects);
}