newgrf_act1.cpp

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/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */
 
#include "../stdafx.h"
#include "../debug.h"
#include "../spritecache.h"
#include "newgrf_bytereader.h"
#include "newgrf_internal.h"
 
#include "../safeguards.h"
 
/* Action 0x01 */
static void NewSpriteSet(ByteReader &buf)
{
  /* Basic format:    <01> <feature> <num-sets> <num-ent>
   * Extended format: <01> <feature> 00 <first-set> <num-sets> <num-ent>
   *
   * B feature       feature to define sprites for
   *                 0, 1, 2, 3: veh-type, 4: train stations
   * E first-set     first sprite set to define
   * B num-sets      number of sprite sets (extended byte in extended format)
   * E num-ent       how many entries per sprite set
   *                 For vehicles, this is the number of different
   *                         vehicle directions in each sprite set
   *                         Set num-dirs=8, unless your sprites are symmetric.
   *                         In that case, use num-dirs=4.
   */
 
  uint8_t  feature   = buf.ReadByte();
  uint16_t num_sets  = buf.ReadByte();
  uint16_t first_set = 0;
 
  if (num_sets == 0 && buf.HasData(3)) {
    /* Extended Action1 format.
     * Some GRFs define zero sets of zero sprites, though there is actually no use in that. Ignore them. */
    first_set = buf.ReadExtendedByte();
    num_sets = buf.ReadExtendedByte();
  }
  uint16_t num_ents = buf.ReadExtendedByte();
 
  if (feature >= GSF_END) {
    _cur.skip_sprites = num_sets * num_ents;
    GrfMsg(1, "NewSpriteSet: Unsupported feature 0x{:02X}, skipping {} sprites", feature, _cur.skip_sprites);
    return;
  }
 
  _cur.AddSpriteSets(feature, _cur.spriteid, first_set, num_sets, num_ents);
 
  GrfMsg(7, "New sprite set at {} of feature 0x{:02X}, consisting of {} sets with {} views each (total {})",
    _cur.spriteid, feature, num_sets, num_ents, num_sets * num_ents
  );
 
  for (int i = 0; i < num_sets * num_ents; i++) {
    _cur.nfo_line++;
    LoadNextSprite(_cur.spriteid++, *_cur.file, _cur.nfo_line);
  }
}
 
/* Action 0x01 (SKIP) */
static void SkipAct1(ByteReader &buf)
{
  buf.ReadByte();
  uint16_t num_sets  = buf.ReadByte();
 
  if (num_sets == 0 && buf.HasData(3)) {
    /* Extended Action1 format.
     * Some GRFs define zero sets of zero sprites, though there is actually no use in that. Ignore them. */
    buf.ReadExtendedByte(); // first_set
    num_sets = buf.ReadExtendedByte();
  }
  uint16_t num_ents = buf.ReadExtendedByte();
 
  _cur.skip_sprites = num_sets * num_ents;
 
  GrfMsg(3, "SkipAct1: Skipping {} sprites", _cur.skip_sprites);
}
 
template <> void GrfActionHandler<0x01>::FileScan(ByteReader &buf) { SkipAct1(buf); }
template <> void GrfActionHandler<0x01>::SafetyScan(ByteReader &buf) { SkipAct1(buf); }
template <> void GrfActionHandler<0x01>::LabelScan(ByteReader &buf) { SkipAct1(buf); }
template <> void GrfActionHandler<0x01>::Init(ByteReader &buf) { SkipAct1(buf); }
template <> void GrfActionHandler<0x01>::Reserve(ByteReader &buf) { SkipAct1(buf); }
template <> void GrfActionHandler<0x01>::Activation(ByteReader &buf) { NewSpriteSet(buf); }