/*

  * This file is part of FFmpeg.

  *

  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *

  * FFmpeg 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 #include "config.h"
 #include "libavutil/attributes.h"
 #include "libavutil/common.h"
 #include "mpegvideodsp.h"
 
 static void gmc1_c(uint8_t *dst, uint8_t *src, int stride, int h,
                    int x16, int y16, int rounder)
 {
     const int A = (16 - x16) * (16 - y16);
     const int B = (x16)      * (16 - y16);
     const int C = (16 - x16) * (y16);
     const int D = (x16)      * (y16);
     int i;
 
     for (i = 0; i < h; i++) {
         dst[0] = (A * src[0] + B * src[1] + C * src[stride + 0] + D * src[stride + 1] + rounder) >> 8;
         dst[1] = (A * src[1] + B * src[2] + C * src[stride + 1] + D * src[stride + 2] + rounder) >> 8;
         dst[2] = (A * src[2] + B * src[3] + C * src[stride + 2] + D * src[stride + 3] + rounder) >> 8;
         dst[3] = (A * src[3] + B * src[4] + C * src[stride + 3] + D * src[stride + 4] + rounder) >> 8;
         dst[4] = (A * src[4] + B * src[5] + C * src[stride + 4] + D * src[stride + 5] + rounder) >> 8;
         dst[5] = (A * src[5] + B * src[6] + C * src[stride + 5] + D * src[stride + 6] + rounder) >> 8;
         dst[6] = (A * src[6] + B * src[7] + C * src[stride + 6] + D * src[stride + 7] + rounder) >> 8;
         dst[7] = (A * src[7] + B * src[8] + C * src[stride + 7] + D * src[stride + 8] + rounder) >> 8;
         dst   += stride;
         src   += stride;
     }
 }
 
 void ff_gmc_c(uint8_t *dst, uint8_t *src, int stride, int h, int ox, int oy,
               int dxx, int dxy, int dyx, int dyy, int shift, int r,
               int width, int height)
 {
     int y, vx, vy;
     const int s = 1 << shift;
 
     width--;
     height--;
 
     for (y = 0; y < h; y++) {
         int x;
 
         vx = ox;
         vy = oy;
         for (x = 0; x < 8; x++) { // FIXME: optimize
             int index;
             int src_x  = vx >> 16;
             int src_y  = vy >> 16;
             int frac_x = src_x & (s - 1);
             int frac_y = src_y & (s - 1);
 
             src_x >>= shift;
             src_y >>= shift;
 
             if ((unsigned) src_x < width) {
                 if ((unsigned) src_y < height) {
                     index = src_x + src_y * stride;
                     dst[y * stride + x] =
                         ((src[index]                        * (s - frac_x) +
                           src[index + 1]          * frac_x) * (s - frac_y) +
                          (src[index + stride]               * (s - frac_x) +
                           src[index + stride + 1] * frac_x) *      frac_y  +
                          r) >> (shift * 2);
                 } else {
                     index = src_x + av_clip(src_y, 0, height) * stride;
                     dst[y * stride + x] =
                         ((src[index]               * (s - frac_x) +
                           src[index + 1] * frac_x) *  s           +
                          r) >> (shift * 2);
                 }
             } else {
                 if ((unsigned) src_y < height) {
                     index = av_clip(src_x, 0, width) + src_y * stride;
                     dst[y * stride + x] =
                         ((src[index]                    * (s - frac_y) +
                           src[index + stride] * frac_y) *  s           +
                          r) >> (shift * 2);
                 } else {
                     index = av_clip(src_x, 0, width) +
                             av_clip(src_y, 0, height) * stride;
                     dst[y * stride + x] = src[index];
                 }
             }
 
             vx += dxx;
             vy += dyx;
         }
         ox += dxy;
         oy += dyy;
     }
 }
 
 av_cold void ff_mpegvideodsp_init(MpegVideoDSPContext *c)
 {
     c->gmc1 = gmc1_c;
     c->gmc  = ff_gmc_c;
 
     if (ARCH_PPC)
         ff_mpegvideodsp_init_ppc(c);
     if (ARCH_X86)
         ff_mpegvideodsp_init_x86(c);
 }