src/mg_biome.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2010-2013 kwolekr, Ryan Kwolek <kwolekr@minetest.net>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "mg_biome.h"
  21 #include "gamedef.h"
  22 #include "nodedef.h"
  23 #include "map.h" //for ManualMapVoxelManipulator
  24 #include "log.h"
  25 #include "util/numeric.h"
  26 #include "main.h"
  27 #include "util/mathconstants.h"
  28 #include "porting.h"
  29
  30 const char *BiomeManager::ELEMENT_TITLE = "biome";
  31
  32
  33 ///////////////////////////////////////////////////////////////////////////////
  34
  35 BiomeManager::BiomeManager(IGameDef *gamedef) :
  36         GenElementManager(gamedef)
  37 {
  38         // Create default biome to be used in case none exist
  39         Biome *b = new Biome;
  40
  41         b->id             = 0;
  42         b->name           = "Default";
  43         b->flags          = 0;
  44         b->depth_top      = 0;
  45         b->depth_filler   = 0;
  46         b->height_min     = -MAP_GENERATION_LIMIT;
  47         b->height_max     = MAP_GENERATION_LIMIT;
  48         b->heat_point     = 0.0;
  49         b->humidity_point = 0.0;
  50
  51         m_resolver->addNode("air",                 "", CONTENT_AIR, &b->c_top);
  52         m_resolver->addNode("air",                 "", CONTENT_AIR, &b->c_filler);
  53         m_resolver->addNode("mapgen_stone",        "", CONTENT_AIR, &b->c_stone);
  54         m_resolver->addNode("mapgen_water_source", "", CONTENT_AIR, &b->c_water);
  55         m_resolver->addNode("air",                 "", CONTENT_AIR, &b->c_dust);
  56         m_resolver->addNode("mapgen_water_source", "", CONTENT_AIR, &b->c_dust_water);
  57
  58         add(b);
  59 }
  60
  61
  62
  63 BiomeManager::~BiomeManager()
  64 {
  65         //if (biomecache)
  66         //      delete[] biomecache;
  67 }
  68
  69
  70
  71 // just a PoC, obviously needs optimization later on (precalculate this)
  72 void BiomeManager::calcBiomes(s16 sx, s16 sy, float *heat_map,
  73         float *humidity_map, s16 *height_map, u8 *biomeid_map)
  74 {
  75         for (s32 i = 0; i != sx * sy; i++)
  76                 biomeid_map[i] = getBiome(heat_map[i], humidity_map[i], height_map[i])->id;
  77 }
  78
  79
  80 Biome *BiomeManager::getBiome(float heat, float humidity, s16 y)
  81 {
  82         Biome *b, *biome_closest = NULL;
  83         float dist_min = FLT_MAX;
  84
  85         for (size_t i = 1; i < m_elements.size(); i++) {
  86                 b = (Biome *)m_elements[i];
  87                 if (!b || y > b->height_max || y < b->height_min)
  88                         continue;
  89
  90                 float d_heat     = heat     - b->heat_point;
  91                 float d_humidity = humidity - b->humidity_point;
  92                 float dist = (d_heat * d_heat) +
  93                                          (d_humidity * d_humidity);
  94                 if (dist < dist_min) {
  95                         dist_min = dist;
  96                         biome_closest = b;
  97                 }
  98         }
  99
 100         return biome_closest ? biome_closest : (Biome *)m_elements[0];
 101 }
 102
 103 void BiomeManager::clear()
 104 {
 105         for (size_t i = 1; i < m_elements.size(); i++) {
 106                 Biome *b = (Biome *)m_elements[i];
 107                 if (!b)
 108                         continue;
 109
 110                 m_resolver->cancelNode(&b->c_top);
 111                 m_resolver->cancelNode(&b->c_filler);
 112                 m_resolver->cancelNode(&b->c_stone);
 113                 m_resolver->cancelNode(&b->c_water);
 114                 m_resolver->cancelNode(&b->c_dust);
 115                 m_resolver->cancelNode(&b->c_dust_water);
 116         }
 117         m_elements.resize(1);
 118 }
 119