text: /****************************************************************************
   * graphics/nxbe/nxbe_redraw.c
   *
   *   Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <stdbool.h>
  #include <errno.h>
  #include <debug.h>
  
  #include <nuttx/nx/nxglib.h>
  
  #include "nxbe.h"
  #include "nxfe.h"
  
  /****************************************************************************
   * Pre-processor Definitions
   ****************************************************************************/
  
  /****************************************************************************
   * Private Types
   ****************************************************************************/
  
  struct nxbe_visible_s
  {
    struct nxbe_clipops_s cops;
    bool visible;
  };
  
  /****************************************************************************
   * Private Data
   ****************************************************************************/
  
  /****************************************************************************
   * Public Data
   ****************************************************************************/
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxbe_clipvisible
   ****************************************************************************/
  
  static void nxbe_clipvisible(FAR struct nxbe_clipops_s *cops,
                               FAR struct nxbe_plane_s *plane,
                               FAR const struct nxgl_rect_s *rect)
  {
    FAR struct nxbe_visible_s *info = (FAR struct nxbe_visible_s *)cops;
    info->visible = true;
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxbe_visible
   *
   * Descripton:
   *   Return true if the point, pt, in window wnd is visible.  pt is in
   *   absolute screen coordinates
   *
   ****************************************************************************/
  
  bool nxbe_visible(FAR struct nxbe_window_s *wnd,
                    FAR const struct nxgl_point_s *pos)
  {
    struct nxbe_visible_s info;
  
    /* Check if the absolute position lies within the window */
  
    if (!nxgl_rectinside(&wnd->bounds, pos))
      {
        return false;
      }
  
    /* If this is the top window, then the psition is visible */
  
    if (!wnd->above)
      {
        return true;
      }
  
    /* The position within the window range, but the window is not at
     * the top.  We will have to work harder to determine if the point
     * visible
     */
  
    info.cops.visible  = nxbe_clipvisible;
    info.cops.obscured = nxbe_clipnull;
    info.visible       = false;
  
    nxbe_clipper(wnd->above, &wnd->bounds, NX_CLIPORDER_DEFAULT,
                 &info.cops, &wnd->be->plane[0]);
  
    return info.visible;
  }
  