text: /****************************************************************************
   * graphics/nxglib/fb/nxglib_getrectangle.c
   *
   *   Copyright (C) 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 <stdint.h>
  
  #include <nuttx/video/fb.h>
  #include <nuttx/nx/nxglib.h>
  
  #include "nxglib_bitblit.h"
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxgl_lowresmemcpy
   ****************************************************************************/
  
  #if NXGLIB_BITSPERPIXEL < 8
  static inline void nxgl_lowresmemcpy(FAR uint8_t *dline, FAR const uint8_t *sline,
                                       unsigned int width,
                                       uint8_t leadmask, uint8_t tailmask)
  {
    FAR const uint8_t *sptr;
    FAR uint8_t *dptr;
    uint8_t mask;
    int lnlen;
  
    /* Handle masking of the fractional initial byte */
  
    mask  = leadmask;
    sptr  = sline;
    dptr  = dline;
    lnlen = width;
  
    if (lnlen > 1 && mask)
       {
         dptr[0] = (dptr[0] & ~mask) | (sptr[0] & mask);
         mask = 0xff;
         dptr++;
         sptr++;
         lnlen--;
       }
  
     /* Handle masking of the fractional final byte */
  
     mask &= tailmask;
     if (lnlen > 0 && mask)
       {
         dptr[lnlen-1] = (dptr[lnlen-1] & ~mask) | (sptr[lnlen-1] & mask);
         lnlen--;
       }
  
     /* Handle all of the unmasked bytes in-between */
  
     if (lnlen > 0)
       {
         NXGL_MEMCPY(dptr, sptr, lnlen);
       }
  }
  #endif
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nxgl_getrectangle_*bpp
   *
   * Description:
   *   Fetch a rectangular region from framebuffer memory.  The source is
   *   expressed as a rectangle.
   *
   ****************************************************************************/
  
  void NXGL_FUNCNAME(nxgl_getrectangle, NXGLIB_SUFFIX)
  (FAR struct fb_planeinfo_s *pinfo, FAR const struct nxgl_rect_s *rect,
   FAR void *dest, unsigned int deststride)
  {
    FAR const uint8_t *sline;
    FAR uint8_t *dline;
    unsigned int width;
    unsigned int fbstride;
    unsigned int rows;
  
  #if NXGLIB_BITSPERPIXEL < 8
    uint8_t leadmask;
    uint8_t tailmask;
  #endif
  
    /* Get the width of the framebuffer in bytes */
  
    fbstride = pinfo->stride;
  
    /* Get the dimensions of the rectangle to copy: width in pixels, height
     * in rows
     */
  
    width = rect->pt2.x - rect->pt1.x + 1;
    rows  = rect->pt2.y - rect->pt1.y + 1;
  
  #if NXGLIB_BITSPERPIXEL < 8
  # ifdef CONFIG_NX_PACKEDMSFIRST
  
    /* Get the mask for pixels that are ordered so that they pack from the
     * MS byte down.
     */
  
    leadmask = (uint8_t)(0xff >> (8 - NXGL_REMAINDERX(rect->pt1.x)));
    tailmask = (uint8_t)(0xff << (8 - NXGL_REMAINDERX(rect->pt2.x-1)));
  # else
    /* Get the mask for pixels that are ordered so that they pack from the
     * LS byte up.
     */
  
    leadmask = (uint8_t)(0xff << (8 - NXGL_REMAINDERX(rect->pt1.x)));
    tailmask = (uint8_t)(0xff >> (8 - NXGL_REMAINDERX(rect->pt1.x-1)));
  # endif
  #endif
  
    /* sline = address of the first pixel in the top row of the source in
     * framebuffer memory
     */
  
    sline = pinfo->fbmem + rect->pt1.y * fbstride + NXGL_SCALEX(rect->pt1.x);
  
    /* dline = address of the first row pixel */
  
    dline = (FAR uint8_t *)dest;
  
    /* Yes.. Copy the rectangle */
  
    while (rows--)
      {
        /* Copy the row */
  
  #if NXGLIB_BITSPERPIXEL < 8
        nxgl_lowresmemcpy(dline, sline, width, leadmask, tailmask);
  #else
        NXGL_MEMCPY(dline, sline, width);
  #endif
        /* Point to the next source/dest row below the current one */
  
        dline += deststride;
        sline += fbstride;
      }
  }
  