/*************************************************************************
 * Copyright (C) 2009 Tavian Barnes <tavianator@gmail.com>               *
 *                                                                       *
 * This file is part of Dimension.                                       *
 *                                                                       *
 * Dimension is free software; you can redistribute it and/or modify it  *
 * under the terms of the GNU General Public License as published by the *
 * Free Software Foundation; either version 3 of the License, or (at     *
 * your option) any later version.                                       *
 *                                                                       *
 * Dimension 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     *
 * General Public License for more details.                              *
 *                                                                       *
 * You should have received a copy of the GNU General Public License     *
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 *************************************************************************/

#include "realize.h"
#include "parse.h"
#include "utility.h"

dmnsn_scene *
dmnsn_realize(const dmnsn_array *astree)
{
  dmnsn_scene *scene = dmnsn_new_scene();
  if (!scene) {
    return NULL;
  }

  /* Background color */
  dmnsn_sRGB background_sRGB = { .R = 0.0, .G = 0.05, .B = 0.1 };
  scene->background = dmnsn_color_from_sRGB(background_sRGB);

  /* Allocate a canvas */
  scene->canvas = dmnsn_new_canvas(768, 480);
  if (!scene->canvas) {
    dmnsn_delete_realized_scene(scene);
    return NULL;
  }

  /* Set up the transformation matrix for the perspective camera */
  dmnsn_matrix trans = dmnsn_scale_matrix(
    dmnsn_vector_construct(
      ((double)scene->canvas->x)/scene->canvas->y, 1.0, 1.0
    )
  );
  trans = dmnsn_matrix_mul(
    dmnsn_translation_matrix(dmnsn_vector_construct(0.0, 0.0, -4.0)),
    trans
  );
  trans = dmnsn_matrix_mul(
    dmnsn_rotation_matrix(dmnsn_vector_construct(0.0, 1.0, 0.0)),
    trans
  );

  /* Create a perspective camera */
  scene->camera = dmnsn_new_perspective_camera();
  if (!scene->camera) {
    dmnsn_delete_realized_scene(scene);
    return NULL;
  }

  return scene;
}

void
dmnsn_delete_realized_scene(dmnsn_scene *scene)
{
  dmnsn_delete_camera(scene->camera);
  dmnsn_delete_canvas(scene->canvas);
  dmnsn_delete_scene(scene);
}