/*
 * This file is part of ELKI:
 * Environment for Developing KDD-Applications Supported by Index-Structures
 *
 * Copyright (C) 2022
 * ELKI Development Team
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */
package elki.visualization.style;

import elki.database.ids.DBIDRef;
import elki.visualization.VisualizationItem;

/**
 * Styling policy.
 * <p>
 * Implementations <em>must</em> implement either {@link ClassStylingPolicy} or
 * {@link SingleObjectsStylingPolicy} interfaces, as most visualizers will only
 * support these known interfaces.
 *
 * @author Erich Schubert
 * @since 0.5.0
 */
public interface StylingPolicy extends VisualizationItem {
  /**
   * Get the color for an individual object.
   * <p>
   * Note: if possible, use a class styling policy which can optimize better.
   *
   * @param id Object ID
   * @return Color value
   */
  int getColorForDBID(DBIDRef id);

  /**
   * Get the Intensity for an individual object.
   * <p>
   * Note: if possible, use a class styling policy which can optimize better.
   *
   * @param id Object ID
   * @return Intensity value
   */
  default double getIntensityForDBID(DBIDRef id) {
    return 1.0;
  }
}
