src/newgrf_animation_base.h

   1 /* $Id$ */
   2
   3 /*
   4  * This file is part of OpenTTD.
   5  * 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.
   6  * 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.
   7  * 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/>.
   8  */
   9
  10 /** @file newgrf_animation_base.h Function implementations related to NewGRF animation. */
  11
  12 /* No inclusion guards as this file must only be included from .cpp files. */
  13
  14 #include "animated_tile_func.h"
  15 #include "core/random_func.hpp"
  16 #include "date_func.h"
  17 #include "viewport_func.h"
  18 #include "newgrf_animation_type.h"
  19 #include "newgrf_callbacks.h"
  20 #include "tile_map.h"
  21
  22 /**
  23  * Helper class for a unified approach to NewGRF animation.
  24  * @tparam Tbase       Instantiation of this class.
  25  * @tparam Tspec       NewGRF specification related to the animated tile.
  26  * @tparam Tobj        Object related to the animated tile.
  27  * @tparam Textra      Custom extra callback data.
  28  * @tparam GetCallback The callback function pointer.
  29  */
  30 template <typename Tbase, typename Tspec, typename Tobj, typename Textra, uint16 (*GetCallback)(CallbackID callback, uint32 param1, uint32 param2, const Tspec *statspec, Tobj *st, TileIndex tile, Textra extra_data)>
  31 struct AnimationBase {
  32         /**
  33          * Animate a single tile.
  34          * @param cb          The callback to actually call.
  35          * @param spec        Specification related to the tile.
  36          * @param obj         Object related to the tile.
  37          * @param tile        Tile to animate changes for.
  38          * @param random_animation Whether to pass random bits to the "next frame" callback.
  39          * @param extra_data  Custom extra callback data.
  40          */
  41         static void AnimateTile(const Tspec *spec, Tobj *obj, TileIndex tile, bool random_animation, Textra extra_data = 0)
  42         {
  43                 assert(spec != NULL);
  44
  45                 /* Acquire the animation speed from the NewGRF. */
  46                 uint8 animation_speed = spec->animation.speed;
  47                 if (HasBit(spec->callback_mask, Tbase::cbm_animation_speed)) {
  48                         uint16 callback = GetCallback(Tbase::cb_animation_speed, 0, 0, spec, obj, tile, extra_data);
  49                         if (callback != CALLBACK_FAILED) {
  50                                 if (callback >= 0x100 && spec->grf_prop.grffile->grf_version >= 8) ErrorUnknownCallbackResult(spec->grf_prop.grffile->grfid, Tbase::cb_animation_speed, callback);
  51                                 animation_speed = Clamp(callback & 0xFF, 0, 16);
  52                         }
  53                 }
  54
  55                 /* An animation speed of 2 means the animation frame changes 4 ticks, and
  56                  * increasing this value by one doubles the wait. 0 is the minimum value
  57                  * allowed for animation_speed, which corresponds to 30ms, and 16 is the
  58                  * maximum, corresponding to around 33 minutes. */
  59                 if (_tick_counter % (1 << animation_speed) != 0) return;
  60
  61                 uint8 frame      = GetAnimationFrame(tile);
  62                 uint8 num_frames = spec->animation.frames;
  63
  64                 bool frame_set_by_callback = false;
  65
  66                 if (HasBit(spec->callback_mask, Tbase::cbm_animation_next_frame)) {
  67                         uint16 callback = GetCallback(Tbase::cb_animation_next_frame, random_animation ? Random() : 0, 0, spec, obj, tile, extra_data);
  68
  69                         if (callback != CALLBACK_FAILED) {
  70                                 frame_set_by_callback = true;
  71
  72                                 switch (callback & 0xFF) {
  73                                         case 0xFF:
  74                                                 DeleteAnimatedTile(tile);
  75                                                 break;
  76
  77                                         case 0xFE:
  78                                                 frame_set_by_callback = false;
  79                                                 break;
  80
  81                                         default:
  82                                                 frame = callback & 0xFF;
  83                                                 break;
  84                                 }
  85
  86                                 /* If the lower 7 bits of the upper byte of the callback
  87                                  * result are not empty, it is a sound effect. */
  88                                 if (GB(callback, 8, 7) != 0 && _settings_client.sound.ambient) PlayTileSound(spec->grf_prop.grffile, GB(callback, 8, 7), tile);
  89                         }
  90                 }
  91
  92                 if (!frame_set_by_callback) {
  93                         if (frame < num_frames) {
  94                                 frame++;
  95                         } else if (frame == num_frames && spec->animation.status == ANIM_STATUS_LOOPING) {
  96                                 /* This animation loops, so start again from the beginning */
  97                                 frame = 0;
  98                         } else {
  99                                 /* This animation doesn't loop, so stay here */
 100                                 DeleteAnimatedTile(tile);
 101                         }
 102                 }
 103
 104                 SetAnimationFrame(tile, frame);
 105                 MarkTileDirtyByTile(tile);
 106         }
 107
 108         /**
 109          * Check a callback to determine what the next animation step is and
 110          * execute that step. This includes stopping and starting animations
 111          * as well as updating animation frames and playing sounds.
 112          * @param cb          The callback to actually call.
 113          * @param spec        Specification related to the tile.
 114          * @param obj         Object related to the tile.
 115          * @param tile        Tile to consider animation changes for.
 116          * @param random_bits Random bits for this update. To be passed as parameter to the NewGRF.
 117          * @param trigger     What triggered this update? To be passed as parameter to the NewGRF.
 118          * @param extra_data  Custom extra data for callback processing.
 119          */
 120         static void ChangeAnimationFrame(CallbackID cb, const Tspec *spec, Tobj *obj, TileIndex tile, uint32 random_bits, uint32 trigger, Textra extra_data = 0)
 121         {
 122                 uint16 callback = GetCallback(cb, random_bits, trigger, spec, obj, tile, extra_data);
 123                 if (callback == CALLBACK_FAILED) return;
 124
 125                 switch (callback & 0xFF) {
 126                         case 0xFD: /* Do nothing. */         break;
 127                         case 0xFE: AddAnimatedTile(tile);    break;
 128                         case 0xFF: DeleteAnimatedTile(tile); break;
 129                         default:
 130                                 SetAnimationFrame(tile, callback);
 131                                 AddAnimatedTile(tile);
 132                                 break;
 133                 }
 134
 135                 /* If the lower 7 bits of the upper byte of the callback
 136                  * result are not empty, it is a sound effect. */
 137                 if (GB(callback, 8, 7) != 0 && _settings_client.sound.ambient) PlayTileSound(spec->grf_prop.grffile, GB(callback, 8, 7), tile);
 138         }
 139 };