clear_cmd.cpp

Go to the documentation of this file.

/*
 * 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 <https://www.gnu.org/licenses/old-licenses/gpl-2.0>.
 */

 
#include "stdafx.h"
#include "clear_map.h"
#include "command_func.h"
#include "landscape.h"
#include "genworld.h"
#include "viewport_func.h"
#include "core/random_func.hpp"
#include "newgrf_generic.h"
#include "landscape_cmd.h"
 
#include "table/strings.h"
#include "table/sprites.h"
#include "table/clear_land.h"
 
#include "safeguards.h"

static CommandCost ClearTile_Clear(TileIndex tile, DoCommandFlags flags)
{
  static constexpr EnumIndexArray<Price, ClearGround, ClearGround::MaxSize> clear_price_table{
    Price::ClearGrass, // Base price for clearing grass.
    Price::ClearRough, // Base price for clearing rough land.
    Price::ClearRocks, // Base price for clearing rocks.
    Price::ClearFields, // Base price for clearing fields.
    Price::ClearRough, // Unused.
    Price::ClearRough, // Base price for clearing desert.
    Price::ClearRough, // Unused.
    Price::ClearRough, // Unused.
  };
  CommandCost price(ExpensesType::Construction);
 
  ClearGround ground = GetClearGround(tile);
  uint8_t density = GetClearDensity(tile);
  if (IsSnowTile(tile)) {
    price.AddCost(_price[clear_price_table[ground]]);
    /* Add a little more for removing snow. */
    price.AddCost(std::abs(_price[Price::ClearRough] - _price[Price::ClearGrass]));
  } else if (ground != ClearGround::Grass || density != 0) {
    price.AddCost(_price[clear_price_table[ground]]);
  }
 
  if (flags.Test(DoCommandFlag::Execute)) DoClearSquare(tile);
 
  return price;
}

void DrawClearLandTile(const TileInfo *ti, uint8_t density)
{
  DrawGroundSprite(_clear_land_sprites_grass[density] + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
}

void DrawRoughLandTile(const TileInfo *ti)
{
  if (ti->tileh != SLOPE_FLAT) {
    DrawGroundSprite(SPR_FLAT_ROUGH_LAND + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
  } else {
    DrawGroundSprite(_landscape_clear_sprites_rough[GB(TileHash(ti->x, ti->y), 0, 3)], PAL_NONE);
  }
}

static void DrawClearLandFence(const TileInfo *ti)
{
  /* combine fences into one sprite object */
  StartSpriteCombine();
 
  SpriteBounds bounds{{}, {TILE_SIZE, TILE_SIZE, 4}, {}};
 
  bounds.extent.z += GetSlopeMaxPixelZ(ti->tileh);
 
  uint fence_nw = GetFence(ti->tile, DiagDirection::NW);
  if (fence_nw != 0) {
    bounds.offset.x = 0;
    bounds.offset.y = -static_cast<int>(TILE_SIZE);
    bounds.offset.z = GetSlopePixelZInCorner(ti->tileh, CORNER_W);
    SpriteID sprite = _clear_land_fence_sprites[fence_nw - 1] + _fence_mod_by_tileh_nw[ti->tileh];
    AddSortableSpriteToDraw(sprite, PAL_NONE, *ti, bounds, false);
  }
 
  uint fence_ne = GetFence(ti->tile, DiagDirection::NE);
  if (fence_ne != 0) {
    bounds.offset.x = -static_cast<int>(TILE_SIZE);
    bounds.offset.y = 0;
    bounds.offset.z = GetSlopePixelZInCorner(ti->tileh, CORNER_E);
    SpriteID sprite = _clear_land_fence_sprites[fence_ne - 1] + _fence_mod_by_tileh_ne[ti->tileh];
    AddSortableSpriteToDraw(sprite, PAL_NONE, *ti, bounds, false);
  }
 
  uint fence_sw = GetFence(ti->tile, DiagDirection::SW);
  uint fence_se = GetFence(ti->tile, DiagDirection::SE);
 
  if (fence_sw != 0 || fence_se != 0) {
    bounds.offset.x = 0;
    bounds.offset.y = 0;
    bounds.offset.z = GetSlopePixelZInCorner(ti->tileh, CORNER_S);
 
    if (fence_sw != 0) {
      SpriteID sprite = _clear_land_fence_sprites[fence_sw - 1] + _fence_mod_by_tileh_sw[ti->tileh];
      AddSortableSpriteToDraw(sprite, PAL_NONE, *ti, bounds, false);
    }
 
    if (fence_se != 0) {
      SpriteID sprite = _clear_land_fence_sprites[fence_se - 1] + _fence_mod_by_tileh_se[ti->tileh];
      AddSortableSpriteToDraw(sprite, PAL_NONE, *ti, bounds, false);
 
    }
  }
  EndSpriteCombine();
}

static void DrawTile_Clear(TileInfo *ti)
{
  if (IsSnowTile(ti->tile)) {
    uint8_t density = GetClearDensity(ti->tile);
    DrawGroundSprite(_clear_land_sprites_snow_desert[density] + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
    if (GetClearGround(ti->tile) == ClearGround::Rocks) {
      /* There 4 levels of snowy overlay rocks, each with 19 sprites. */
      ++density;
      DrawGroundSprite(SPR_OVERLAY_ROCKS_BASE + (density * 19) + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
    }
 
    DrawBridgeMiddle(ti, {});
    return;
  }
 
  switch (GetClearGround(ti->tile)) {
    case ClearGround::Grass:
      DrawClearLandTile(ti, GetClearDensity(ti->tile));
      break;
 
    case ClearGround::Rough:
      DrawRoughLandTile(ti);
      break;
 
    case ClearGround::Rocks:
      if (GetTropicZone(ti->tile) == TropicZone::Desert) {
        DrawGroundSprite(_clear_land_sprites_snow_desert[GetClearDensity(ti->tile)] + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
        DrawGroundSprite(SPR_OVERLAY_ROCKS_BASE + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
      } else {
        DrawGroundSprite((HasGrfMiscBit(GrfMiscBit::SecondRockyTileSet) && (TileHash(ti->x, ti->y) & 1) ? SPR_FLAT_ROCKY_LAND_2 : SPR_FLAT_ROCKY_LAND_1) + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
      }
      break;
 
    case ClearGround::Fields:
      DrawGroundSprite(_clear_land_sprites_farmland[GetFieldType(ti->tile)] + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
      DrawClearLandFence(ti);
      break;
 
    case ClearGround::Desert:
      DrawGroundSprite(_clear_land_sprites_snow_desert[GetClearDensity(ti->tile)] + SlopeToSpriteOffset(ti->tileh), PAL_NONE);
      break;
 
    default:
      NOT_REACHED();
  }
 
  DrawBridgeMiddle(ti, {});
}

static int GetSlopePixelZ_Clear(TileIndex tile, uint x, uint y, [[maybe_unused]] bool ground_vehicle)
{
  auto [tileh, z] = GetTilePixelSlope(tile);
 
  return z + GetPartialPixelZ(x & 0xF, y & 0xF, tileh);
}
 
static void UpdateFences(TileIndex tile)
{
  assert(IsTileType(tile, TileType::Clear) && IsClearGround(tile, ClearGround::Fields));
  bool dirty = false;
 
  for (DiagDirection dir : EnumRange(DiagDirection::End)) {
    if (GetFence(tile, dir) != 0) continue;
    TileIndex neighbour = tile + TileOffsByDiagDir(dir);
    if (IsTileType(neighbour, TileType::Clear) && IsClearGround(neighbour, ClearGround::Fields)) continue;
    SetFence(tile, dir, 3);
    dirty = true;
  }
 
  if (dirty) MarkTileDirtyByTile(tile);
}
 

static void TileLoopClearAlps(TileIndex tile)
{
  int k = GetTileZ(tile) - GetSnowLine() + 1;
 
  if (!IsSnowTile(tile)) {
    /* Below the snow line, do nothing if no snow. */
    /* At or above the snow line, make snow tile if needed. */
    if (k >= 0) {
      /* Snow density is started at 0 so that it can gradually reach the required density. */
      MakeSnow(tile, 0);
      MarkTileDirtyByTile(tile);
    }
    return;
  }
 
  /* Update snow density. */
  uint current_density = GetClearDensity(tile);
  uint req_density = (k < 0) ? 0u : std::min<uint>(k, 3u);
 
  if (current_density == req_density) {
    /* Density at the required level. */
    if (k >= 0) return;
    ClearSnow(tile);
  } else {
    AddClearDensity(tile, current_density < req_density ? 1 : -1);
  }
 
  MarkTileDirtyByTile(tile);
}

static inline bool NeighbourIsNormal(TileIndex tile)
{
  for (DiagDirection dir : EnumRange(DiagDirection::End)) {
    TileIndex t = tile + TileOffsByDiagDir(dir);
    if (!IsValidTile(t)) continue;
    if (GetTropicZone(t) != TropicZone::Desert) return true;
    if (HasTileWaterClass(t) && GetWaterClass(t) == WaterClass::Sea) return true;
  }
  return false;
}
 
static void TileLoopClearDesert(TileIndex tile)
{
  ClearGround ground = GetClearGround(tile);
 
  /* Current desert level - 0 if it is not desert */
  uint current = 0;
  if (ground == ClearGround::Desert || ground == ClearGround::Rocks) current = GetClearDensity(tile);
 
  /* Expected desert level - 0 if it shouldn't be desert */
  uint expected = 0;
  if (GetTropicZone(tile) == TropicZone::Desert) {
    expected = NeighbourIsNormal(tile) ? 1 : 3;
  }
 
  if (current == expected) return;
 
  if (ground == ClearGround::Rocks) {
    SetClearGroundDensity(tile, ClearGround::Rocks, expected);
  } else if (expected == 0) {
    SetClearGroundDensity(tile, ClearGround::Grass, 3);
  } else {
    /* Transition from clear to desert is not smooth (after clearing desert tile) */
    SetClearGroundDensity(tile, ClearGround::Desert, expected);
  }
 
  MarkTileDirtyByTile(tile);
}

static void TileLoop_Clear(TileIndex tile)
{
  AmbientSoundEffect(tile);
 
  switch (_settings_game.game_creation.landscape) {
    case LandscapeType::Tropic: TileLoopClearDesert(tile); break;
    case LandscapeType::Arctic: TileLoopClearAlps(tile);   break;
    default: break;
  }
 
  if (IsSnowTile(tile)) return;
 
  switch (GetClearGround(tile)) {
    case ClearGround::Grass:
      if (GetClearDensity(tile) == 3) return;
 
      if (_game_mode != GameMode::Editor) {
        if (GetClearCounter(tile) < 7) {
          AddClearCounter(tile, 1);
          return;
        } else {
          SetClearCounter(tile, 0);
          AddClearDensity(tile, 1);
        }
      } else {
        SetClearGroundDensity(tile, GB(Random(), 0, 8) > 21 ? ClearGround::Grass : ClearGround::Rough, 3);
      }
      break;
 
    case ClearGround::Fields:
      UpdateFences(tile);
 
      if (_game_mode == GameMode::Editor) return;
 
      if (GetClearCounter(tile) < 7) {
        AddClearCounter(tile, 1);
        return;
      } else {
        SetClearCounter(tile, 0);
      }
 
      if (GetIndustryIndexOfField(tile) == IndustryID::Invalid() && GetFieldType(tile) >= 7) {
        /* This farmfield is no longer farmfield, so make it grass again */
        MakeClear(tile, ClearGround::Grass, 2);
      } else {
        uint field_type = GetFieldType(tile);
        field_type = (field_type < 8) ? field_type + 1 : 0;
        SetFieldType(tile, field_type);
      }
      break;
 
    default:
      return;
  }
 
  MarkTileDirtyByTile(tile);
}
 
void GenerateClearTile()
{
  uint i, gi;
  TileIndex tile;
 
  /* add rough tiles */
  i = Map::ScaleBySize(GB(Random(), 0, 10) + 0x400);
  gi = Map::ScaleBySize(GB(Random(), 0, 7) + 0x80);
 
  SetGeneratingWorldProgress(GenWorldProgress::RoughAndRocks, gi + i);
  do {
    IncreaseGeneratingWorldProgress(GenWorldProgress::RoughAndRocks);
    tile = RandomTile();
    if (IsTileType(tile, TileType::Clear) && !IsClearGround(tile, ClearGround::Desert)) SetClearGroundDensity(tile, ClearGround::Rough, 3);
  } while (--i);
 
  /* add rocky tiles */
  i = gi;
  do {
    uint32_t r = Random();
    tile = RandomTileSeed(r);
 
    IncreaseGeneratingWorldProgress(GenWorldProgress::RoughAndRocks);
    if (IsTileType(tile, TileType::Clear)) {
      uint j = GB(r, 16, 4) + 5;
      for (;;) {
        TileIndex tile_new;
 
        SetClearGroundDensity(tile, ClearGround::Rocks, 3);
        MarkTileDirtyByTile(tile);
        do {
          if (--j == 0) goto get_out;
          tile_new = tile + TileOffsByDiagDir((DiagDirection)GB(Random(), 0, 2));
        } while (!IsTileType(tile_new, TileType::Clear));
        tile = tile_new;
      }
get_out:;
    }
  } while (--i);
}

static void GetTileDesc_Clear(TileIndex tile, TileDesc &td)
{
  /* Each pair holds a normal and a snowy ClearGround description. */
  static constexpr EnumIndexArray<std::pair<StringID, StringID>, ClearGround, ClearGround::MaxSize> clear_land_str{{{
    {STR_LAI_CLEAR_DESCRIPTION_GRASS,      STR_LAI_CLEAR_DESCRIPTION_SNOWY_GRASS}, // Description for grass.
    {STR_LAI_CLEAR_DESCRIPTION_ROUGH_LAND, STR_LAI_CLEAR_DESCRIPTION_SNOWY_ROUGH_LAND}, // Description for rough land.
    {STR_LAI_CLEAR_DESCRIPTION_ROCKS,      STR_LAI_CLEAR_DESCRIPTION_SNOWY_ROCKS}, // Description for rocks.
    {STR_LAI_CLEAR_DESCRIPTION_FIELDS,     STR_EMPTY}, // Description for fields.
    {STR_EMPTY,                            STR_EMPTY}, // unused entry does not appear in the map.
    {STR_LAI_CLEAR_DESCRIPTION_DESERT,     STR_EMPTY}, // Description for desert.
    {STR_EMPTY,                            STR_EMPTY}, // unused entry does not appear in the map.
    {STR_EMPTY,                            STR_EMPTY}, // unused entry does not appear in the map.
  }}};
 
  if (!IsSnowTile(tile) && IsClearGround(tile, ClearGround::Grass) && GetClearDensity(tile) == 0) {
    td.str = STR_LAI_CLEAR_DESCRIPTION_BARE_LAND;
  } else {
    const auto &[name, snowy_name] = clear_land_str[GetClearGround(tile)];
    td.str = IsSnowTile(tile) ? snowy_name : name;
  }
  td.owner[0] = GetTileOwner(tile);
}

extern const TileTypeProcs _tile_type_clear_procs = {
  .draw_tile_proc = DrawTile_Clear,
  .get_slope_pixel_z_proc = GetSlopePixelZ_Clear,
  .clear_tile_proc = ClearTile_Clear,
  .get_tile_desc_proc = GetTileDesc_Clear,
  .tile_loop_proc = TileLoop_Clear,
  .terraform_tile_proc = [](TileIndex tile, DoCommandFlags flags, int, Slope) { return Command<Commands::LandscapeClear>::Do(flags, tile); },
  .check_build_above_proc = [](TileIndex, DoCommandFlags, Axis, int) { return CommandCost(); }, // Can always build above clear tiles
};