/* Copyright (C) 2011 Wildfire Games. * This file is part of 0 A.D. * * 0 A.D. 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, either version 2 of the License, or * (at your option) any later version. * * 0 A.D. 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 0 A.D. If not, see . */ /* * Describes ground via heightmap and array of CPatch. */ #ifndef INCLUDED_TERRAIN #define INCLUDED_TERRAIN #include "maths/Vector3D.h" #include "maths/Fixed.h" #include "graphics/SColor.h" class CPatch; class CMiniPatch; class CFixedVector3D; class CStr8; class CBoundingBoxAligned; /////////////////////////////////////////////////////////////////////////////// // Terrain Constants: /// metres [world space units] per tile in x and z const ssize_t TERRAIN_TILE_SIZE = 4; /// number of u16 height units per metre const ssize_t HEIGHT_UNITS_PER_METRE = 732; // == approx int(256.0f/0.35f) /// metres per u16 height unit const float HEIGHT_SCALE = 1.f / HEIGHT_UNITS_PER_METRE; /////////////////////////////////////////////////////////////////////////////// // CTerrain: main terrain class; contains the heightmap describing elevation // data, and the smaller subpatches that form the terrain class CTerrain { public: CTerrain(); ~CTerrain(); // Coordinate naming convention: world-space coordinates are float x,z; // tile-space coordinates are ssize_t i,j. rationale: signed types can // more efficiently be converted to/from floating point. use ssize_t // instead of int/long because these are sizes. bool Initialize(ssize_t patchesPerSide, const u16* ptr); // return number of vertices along edge of the terrain ssize_t GetVerticesPerSide() const { return m_MapSize; } // return number of tiles along edge of the terrain ssize_t GetTilesPerSide() const { return GetVerticesPerSide()-1; } // return number of patches along edge of the terrain ssize_t GetPatchesPerSide() const { return m_MapSizePatches; } float GetMinX() const { return 0.0f; } float GetMinZ() const { return 0.0f; } float GetMaxX() const { return (float)((m_MapSize-1) * TERRAIN_TILE_SIZE); } float GetMaxZ() const { return (float)((m_MapSize-1) * TERRAIN_TILE_SIZE); } bool IsOnMap(float x, float z) const { return ((x >= GetMinX()) && (x < GetMaxX()) && (z >= GetMinZ()) && (z < GetMaxZ())); } CStr8 GetMovementClass(ssize_t i, ssize_t j) const; float GetVertexGroundLevel(ssize_t i, ssize_t j) const; fixed GetVertexGroundLevelFixed(ssize_t i, ssize_t j) const; float GetExactGroundLevel(float x, float z) const; fixed GetExactGroundLevelFixed(fixed x, fixed z) const; // get the approximate slope (0 = horizontal, 0.5 = 30 degrees, 1.0 = 45 degrees, etc) fixed GetSlopeFixed(ssize_t i, ssize_t j) const; // Returns true if the triangulation diagonal for tile (i, j) // should be in the direction (1,-1); false if it should be (1,1) bool GetTriangulationDir(ssize_t i, ssize_t j) const; // resize this terrain such that each side has given number of patches void Resize(ssize_t size); // set up a new heightmap from 16 bit data; assumes heightmap matches current terrain size void SetHeightMap(u16* heightmap); // return a pointer to the heightmap u16* GetHeightMap() const { return m_Heightmap; } // get patch at given coordinates, expressed in patch-space; return 0 if // coordinates represent patch off the edge of the map CPatch* GetPatch(ssize_t i, ssize_t j) const; // get tile at given coordinates, expressed in tile-space; return 0 if // coordinates represent tile off the edge of the map CMiniPatch* GetTile(ssize_t i, ssize_t j) const; // calculate the position of a given vertex void CalcPosition(ssize_t i, ssize_t j, CVector3D& pos) const; void CalcPositionFixed(ssize_t i, ssize_t j, CFixedVector3D& pos) const; // calculate the vertex under a given position (rounding down coordinates) static void CalcFromPosition(const CVector3D& pos, ssize_t& i, ssize_t& j) { i = (ssize_t)(pos.X/TERRAIN_TILE_SIZE); j = (ssize_t)(pos.Z/TERRAIN_TILE_SIZE); } // calculate the vertex under a given position (rounding down coordinates) static void CalcFromPosition(float x, float z, ssize_t& i, ssize_t& j) { i = (ssize_t)(x/TERRAIN_TILE_SIZE); j = (ssize_t)(z/TERRAIN_TILE_SIZE); } // calculate the normal at a given vertex void CalcNormal(ssize_t i, ssize_t j, CVector3D& normal) const; void CalcNormalFixed(ssize_t i, ssize_t j, CFixedVector3D& normal) const; CVector3D CalcExactNormal(float x, float z) const; // flatten out an area of terrain (specified in world space coords); return // the average height of the flattened area float FlattenArea(float x0, float x1, float z0, float z1); // mark a specific square of tiles as dirty - use this after modifying the heightmap void MakeDirty(ssize_t i0, ssize_t j0, ssize_t i1, ssize_t j1, int dirtyFlags); // mark the entire map as dirty void MakeDirty(int dirtyFlags); /** * Returns a 3D bounding box encompassing the given vertex range (inclusive) */ CBoundingBoxAligned GetVertexesBound(ssize_t i0, ssize_t j0, ssize_t i1, ssize_t j1); // get the base colour for the terrain (typically pure white - other colours // will interact badly with LOS - but used by the Actor Viewer tool) SColor4ub GetBaseColour() const { return m_BaseColour; } // set the base colour for the terrain void SetBaseColour(SColor4ub colour) { m_BaseColour = colour; } private: // delete any data allocated by this terrain void ReleaseData(); // setup patch pointers etc void InitialisePatches(); // size of this map in each direction, in vertices; ie. total tiles = sqr(m_MapSize-1) ssize_t m_MapSize; // size of this map in each direction, in patches; total patches = sqr(m_MapSizePatches) ssize_t m_MapSizePatches; // the patches comprising this terrain CPatch* m_Patches; // 16-bit heightmap data u16* m_Heightmap; // base colour (usually white) SColor4ub m_BaseColour; }; #endif