/*
 * 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., 51 Franklin St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "../gstgleffects.h"

static void
gst_gl_effects_identity_callback (gint width, gint height, guint texture,
    gpointer data)
{
  GstGLEffects *effects = GST_GL_EFFECTS (data);
  GstGLFilter *filter = GST_GL_FILTER (effects);
  GstGLContext *context = GST_GL_BASE_FILTER (filter)->context;
  GstGLFuncs *gl = context->gl_vtable;
  GstGLShader *shader;

#if GST_GL_HAVE_OPENGL
  if (USING_OPENGL (context)) {
    gl->MatrixMode (GL_PROJECTION);
    gl->LoadIdentity ();
  }
#endif

  shader = g_hash_table_lookup (effects->shaderstable, "identity0");
  if (!shader) {
    GError *error = NULL;

    if (!(shader = gst_gl_shader_new_default (context, &error))) {
      GST_ELEMENT_ERROR (effects, RESOURCE, NOT_FOUND,
          ("Failed to initialize identity shader: %s", error->message), (NULL));
      return;
    }

    filter->draw_attr_position_loc =
        gst_gl_shader_get_attribute_location (shader, "a_position");
    filter->draw_attr_texture_loc =
        gst_gl_shader_get_attribute_location (shader, "a_texcoord");

    g_hash_table_insert (effects->shaderstable, (gchar *) "identity0", shader);
  }
  gst_gl_shader_use (shader);

  gl->ActiveTexture (GL_TEXTURE0);
  gl->BindTexture (GL_TEXTURE_2D, texture);

  gst_gl_shader_set_uniform_1i (shader, "tex", 0);

  gst_gl_filter_draw_texture (filter, texture, width, height);
}

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

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