minetest/src/voxelalgorithms.h

158 lines
4.5 KiB
C++

/*
Minetest
Copyright (C) 2010-2013 celeron55, Perttu Ahola <celeron55@gmail.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
This program 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 Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#pragma once
#include "voxel.h"
#include "mapnode.h"
#include "util/container.h"
class Map;
class ServerMap;
class MapBlock;
class MMVManip;
namespace voxalgo
{
/*!
* Updates the lighting on the map.
* The result will be correct only if
* no nodes were changed except the given ones.
* Before calling this procedure make sure that all new nodes on
* the map have zero light level!
*
* \param oldnodes contains the MapNodes that were replaced by the new
* MapNodes and their positions
* \param modified_blocks output, contains all map blocks that
* the function modified
*/
void update_lighting_nodes(
Map *map,
const std::vector<std::pair<v3s16, MapNode>> &oldnodes,
std::map<v3s16, MapBlock*> &modified_blocks);
/*!
* Updates borders of the given mapblock.
* Only updates if the block was marked with incomplete
* lighting and the neighbor is also loaded.
*
* \param block the block to update
* \param modified_blocks output, contains all map blocks that
* the function modified
*/
void update_block_border_lighting(Map *map, MapBlock *block,
std::map<v3s16, MapBlock*> &modified_blocks);
/*!
* Copies back nodes from a voxel manipulator
* to the map and updates lighting.
* For server use only.
*
* \param modified_blocks output, contains all map blocks that
* the function modified
*/
void blit_back_with_light(ServerMap *map, MMVManip *vm,
std::map<v3s16, MapBlock*> *modified_blocks);
/*!
* Corrects the light in a map block.
* For server use only.
*
* \param block the block to update
*/
void repair_block_light(ServerMap *map, MapBlock *block,
std::map<v3s16, MapBlock*> *modified_blocks);
/*!
* This class iterates trough voxels that intersect with
* a line. The collision detection does not see nodeboxes,
* every voxel is a cube and is returned.
* This iterator steps to all nodes exactly once.
*/
struct VoxelLineIterator
{
public:
//! Starting position of the line in world coordinates.
v3f m_start_position;
//! Direction and length of the line in world coordinates.
v3f m_line_vector;
/*!
* Each component stores the next smallest positive number, by
* which multiplying the line's vector gives a vector that ends
* on the intersection of two nodes.
*/
v3f m_next_intersection_multi { 10000.0f, 10000.0f, 10000.0f };
/*!
* Each component stores the smallest positive number, by which
* m_next_intersection_multi's components can be increased.
*/
v3f m_intersection_multi_inc { 10000.0f, 10000.0f, 10000.0f };
/*!
* Direction of the line. Each component can be -1 or 1 (if a
* component of the line's vector is 0, then there will be 1).
*/
v3s16 m_step_directions { 1, 1, 1 };
//! Position of the current node.
v3s16 m_current_node_pos;
//! Index of the current node
s16 m_current_index = 0;
//! Position of the start node.
v3s16 m_start_node_pos;
//! Index of the last node
s16 m_last_index;
/*!
* Creates a voxel line iterator with the given line.
* @param start_position starting point of the line
* in voxel coordinates
* @param line_vector length and direction of the
* line in voxel coordinates. start_position+line_vector
* is the end of the line
*/
VoxelLineIterator(const v3f &start_position,const v3f &line_vector);
/*!
* Steps to the next voxel.
* Updates m_current_node_pos and
* m_previous_node_pos.
* Note that it works even if hasNext() is false,
* continuing the line as a ray.
*/
void next();
/*!
* Returns true if the next voxel intersects the given line.
*/
inline bool hasNext() const
{
return m_current_index < m_last_index;
}
/*!
* Returns how many times next() must be called until
* voxel==m_current_node_pos.
* If voxel does not intersect with the line,
* the result is undefined.
*/
s16 getIndex(v3s16 voxel);
};
} // namespace voxalgo