server/src/game/Object/ObjectPosSelector.cpp
2020-02-17 12:08:28 +00:00

238 lines
8.2 KiB
C++

/**
* MaNGOS is a full featured server for World of Warcraft, supporting
* the following clients: 1.12.x, 2.4.3, 3.3.5a, 4.3.4a and 5.4.8
*
* Copyright (C) 2005-2016 MaNGOS project <https://getmangos.eu>
*
* This program 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.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* World of Warcraft, and all World of Warcraft or Warcraft art, images,
* and lore are copyrighted by Blizzard Entertainment, Inc.
*/
#include "ObjectPosSelector.h"
#include "Object.h"
// The bigger this value, the more space npcs require around their target
#define OCCUPY_POS_ANGLE_ATAN_FACTOR 1.8f
ObjectPosSelector::ObjectPosSelector(float x, float y, float dist, float searchedForSize, WorldObject const* searchPosFor) :
m_centerX(x), m_centerY(y), m_searcherDist(dist), m_searchPosFor(searchPosFor)
{
// if size == 0, m_anglestep will become 0 -> freeze
if (searchedForSize == 0.0f)
searchedForSize = DEFAULT_WORLD_OBJECT_SIZE;
// undefined behaviour
if (m_searcherDist == 0.0f)
m_searcherDist = DEFAULT_WORLD_OBJECT_SIZE;
m_searchedForReqHAngle = atan(OCCUPY_POS_ANGLE_ATAN_FACTOR * searchedForSize / m_searcherDist);
// Really init in InitilizeAngle
m_nextUsedAreaItr[USED_POS_PLUS] = m_UsedAreaLists[USED_POS_PLUS].begin();
m_nextUsedAreaItr[USED_POS_MINUS] = m_UsedAreaLists[USED_POS_MINUS].begin();
m_stepAngle[USED_POS_PLUS] = 0.0f;
m_stepAngle[USED_POS_MINUS] = 0.0f;
}
/**
* Add used area (circle) near target object excluded from possible searcher position
*
*
* @param obj Object that occupies area
* @param angle Angle of used circle center point from target-searcher line
* @param dist Distance from target object center point to used circle center point
*
* Used circles data stored as projections to searcher dist size circle as angle coordinate and half angle size
*/
void ObjectPosSelector::AddUsedArea(WorldObject const* obj, float angle, float dist)
{
MANGOS_ASSERT(obj);
// skip some unexpected results.
if (dist == 0.0f)
return;
// (half) angle that obj occupies
float sr_angle = atan(OCCUPY_POS_ANGLE_ATAN_FACTOR * obj->GetObjectBoundingRadius() / dist);
if (angle >= 0)
m_UsedAreaLists[USED_POS_PLUS].insert(UsedArea(angle, OccupiedArea(sr_angle, obj)));
else
m_UsedAreaLists[USED_POS_MINUS].insert(UsedArea(-angle, OccupiedArea(sr_angle, obj)));
}
/**
* Check searcher circle not intercepting with used circle
*
* @param usedArea Used circle as projection to searcher distance circle in angles form
* @param side Side of used circle
* @param angle Checked angle
*
* @return true, if used circle not intercepted with searcher circle in terms projection angles
*/
bool ObjectPosSelector::CheckAngle(UsedArea const& usedArea, UsedAreaSide side, float angle) const
{
float used_offset = usedArea.second.angleOffset;
float used_angle = usedArea.first * SignOf(side);
// check first left/right used angles if exists
return fabs(used_angle - angle) > used_offset || (m_searchPosFor && usedArea.second.occupyingObj == m_searchPosFor);
}
/**
* Check original (0.0f) angle fit to existed used area excludes
*
* @return true, if 0.0f angle with m_searcher_halfangle*2 angle size not intercept with used circles
*/
bool ObjectPosSelector::CheckOriginalAngle() const
{
// check first left/right used angles if exists
return (m_UsedAreaLists[USED_POS_PLUS].empty() || CheckAngle(*m_UsedAreaLists[USED_POS_PLUS].begin(), USED_POS_PLUS, 0.0f)) &&
(m_UsedAreaLists[USED_POS_MINUS].empty() || CheckAngle(*m_UsedAreaLists[USED_POS_MINUS].begin(), USED_POS_MINUS, 0.0f));
}
/**
* Initialize data for search angles starting from first possible angle at both sides
*/
void ObjectPosSelector::InitializeAngle()
{
InitializeAngle(USED_POS_PLUS);
InitializeAngle(USED_POS_MINUS);
}
/**
* Initialize data for search angles starting from first possible angle at side
*/
void ObjectPosSelector::InitializeAngle(UsedAreaSide side)
{
m_nextUsedAreaItr[side] = m_UsedAreaLists[side].begin();
// if another side not alow use 0.0f angle calculate possible value in 0..m_searchedForReqHAngle range
if (!m_UsedAreaLists[~side].empty())
{
UsedArea const& otherArea = *m_UsedAreaLists[~side].begin();
m_stepAngle[side] = std::max(m_searchedForReqHAngle + otherArea.second.angleOffset - otherArea.first, 0.0f);
}
else // Other side empty. start from 0
m_stepAngle[side] = 0.0f;
// As m_stepAngle will be incremented first in ::NextSideAngle
m_stepAngle[side] -= m_searchedForReqHAngle;
}
/**
* Find next angle in free area
*
* @param angle Return at success found angle
*
* @return true, if angle found
*/
bool ObjectPosSelector::NextAngle(float& angle)
{
// loop until both side fail and leave 0..PI
for (;;)
{
// ++ direction less updated
if (m_stepAngle[USED_POS_PLUS] < M_PI_F && m_stepAngle[USED_POS_PLUS] <= m_stepAngle[USED_POS_MINUS])
{
if (NextSideAngle(USED_POS_PLUS, angle))
return true;
}
// -- direction less updated
else if (m_stepAngle[USED_POS_MINUS] < M_PI_F)
{
if (NextSideAngle(USED_POS_MINUS, angle))
return true;
}
// both sides finishes
else
break;
}
// no angles
return false;
}
/**
* Find next angle at side
*
* @param side Side of angle
* @param angle Return at success found angle
*
* @return true, if angle found
*
*/
bool ObjectPosSelector::NextSideAngle(UsedAreaSide side, float& angle)
{
// next possible angle
m_stepAngle[side] += (m_searchedForReqHAngle + 0.01);
// prevent jump to another side
if (m_stepAngle[side] > M_PI_F)
return false;
// no used area anymore on this side
if (m_nextUsedAreaItr[side] == m_UsedAreaLists[side].end())
{
angle = m_stepAngle[side] * SignOf(side);
return true;
}
// Already occupied and no better found
if ((m_searchPosFor && m_nextUsedAreaItr[side]->second.occupyingObj == m_searchPosFor) ||
// Next occupied is too far away
(m_stepAngle[side] + m_searchedForReqHAngle < m_nextUsedAreaItr[side]->first - m_nextUsedAreaItr[side]->second.angleOffset))
{
angle = m_stepAngle[side] * SignOf(side);
return true;
}
// angle set at first possible pos after passed m_nextUsedAreaItr
m_stepAngle[side] = m_nextUsedAreaItr[side]->first + m_nextUsedAreaItr[side]->second.angleOffset;
++m_nextUsedAreaItr[side];
return false;
}
/**
* Find next angle in used area, that used if no angle found in free area with LoS
*
* @param angle Return at success found angle
*
* @return true, if angle found
*/
bool ObjectPosSelector::NextUsedAngle(float& angle)
{
if (m_nextUsedAreaItr[USED_POS_PLUS] == m_UsedAreaLists[USED_POS_PLUS].end() &&
m_nextUsedAreaItr[USED_POS_MINUS] == m_UsedAreaLists[USED_POS_MINUS].end())
return false;
// ++ direction less updated
if (m_nextUsedAreaItr[USED_POS_PLUS] != m_UsedAreaLists[USED_POS_PLUS].end() &&
(m_nextUsedAreaItr[USED_POS_MINUS] == m_UsedAreaLists[USED_POS_MINUS].end() ||
m_nextUsedAreaItr[USED_POS_PLUS]->first <= m_nextUsedAreaItr[USED_POS_MINUS]->first))
{
angle = m_nextUsedAreaItr[USED_POS_PLUS]->first * SignOf(USED_POS_PLUS);
++m_nextUsedAreaItr[USED_POS_PLUS];
}
else
{
angle = m_nextUsedAreaItr[USED_POS_MINUS]->first * SignOf(USED_POS_MINUS);
++m_nextUsedAreaItr[USED_POS_MINUS];
}
return true;
}