minetest/src/voxelalgorithms.h
Dániel Juhász ab371cc934 Light calculation: New bulk node lighting code
This commit introduces a new bulk node lighting algorithm to minimize
lighting bugs during l-system tree generation, schematic placement and
non-mapgen-object lua voxelmanip light calculation.

If the block above the changed area is not loaded, it gets loaded to avoid
lighting bugs.
Light is updated as soon as write_to_map is called on a voxel manipulator,
therefore update_map does nothing.
2017-03-11 02:06:18 +00:00

165 lines
4.7 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.
*/
#ifndef VOXELALGORITHMS_HEADER
#define VOXELALGORITHMS_HEADER
#include "voxel.h"
#include "mapnode.h"
#include "util/container.h"
#include "util/cpp11_container.h"
class Map;
class ServerMap;
class MapBlock;
class MMVManip;
namespace voxalgo
{
// TODO: Move unspreadLight and spreadLight from VoxelManipulator to here
void setLight(VoxelManipulator &v, VoxelArea a, u8 light,
INodeDefManager *ndef);
void clearLightAndCollectSources(VoxelManipulator &v, VoxelArea a,
enum LightBank bank, INodeDefManager *ndef,
std::set<v3s16> & light_sources,
std::map<v3s16, u8> & unlight_from);
struct SunlightPropagateResult
{
bool bottom_sunlight_valid;
SunlightPropagateResult(bool bottom_sunlight_valid_):
bottom_sunlight_valid(bottom_sunlight_valid_)
{}
};
SunlightPropagateResult propagateSunlight(VoxelManipulator &v, VoxelArea a,
bool inexistent_top_provides_sunlight,
std::set<v3s16> & light_sources,
INodeDefManager *ndef);
/*!
* 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,
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);
/*!
* 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;
/*!
* Each component stores the smallest positive number, by which
* m_next_intersection_multi's components can be increased.
*/
v3f m_intersection_multi_inc;
/*!
* 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;
//! Position of the current node.
v3s16 m_current_node_pos;
//! If true, the next node will intersect the line, too.
bool m_has_next;
/*!
* 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_has_next; }
};
} // namespace voxalgo
#endif