Refactor PathFinder functions to be useable by AiWander

This avoids having to duplicate the distanceSquared and getClosestPoint functions.
pull/927/head
Austin Salgat 9 years ago
parent 96231e17f0
commit 38f5a225ea

@ -39,33 +39,6 @@ namespace MWMechanics
// distance must be long enough that NPC will need to move to get there.
static const int MINIMUM_WANDER_DISTANCE = DESTINATION_TOLERANCE * 2;
float distanceSquared(ESM::Pathgrid::Point point, const osg::Vec3f& pos)
{
return (MWMechanics::PathFinder::MakeOsgVec3(point) - pos).length2();
}
int getClosestPoint(const ESM::Pathgrid* grid, const osg::Vec3f& pos)
{
assert(grid && !grid->mPoints.empty());
float distanceBetween = distanceSquared(grid->mPoints[0], pos);
int closestIndex = 0;
// TODO: if this full scan causes performance problems mapping pathgrid
// points to a quadtree may help
for(unsigned int counter = 1; counter < grid->mPoints.size(); counter++)
{
float potentialDistBetween = distanceSquared(grid->mPoints[counter], pos);
if(potentialDistBetween < distanceBetween)
{
distanceBetween = potentialDistBetween;
closestIndex = counter;
}
}
return closestIndex;
}
const std::string AiWander::sIdleSelectToGroupName[GroupIndex_MaxIdle - GroupIndex_MinIdle + 1] =
{
std::string("idle2"),
@ -779,7 +752,7 @@ namespace MWMechanics
CoordinateConverter(cell).toLocal(npcPos);
// Find closest pathgrid point
int closestPointIndex = getClosestPoint(pathgrid, npcPos);
int closestPointIndex = PathFinder::GetClosestPoint(pathgrid, npcPos);
// mAllowedNodes for this actor with pathgrid point indexes based on mDistance
// and if the point is connected to the closest current point

@ -10,43 +10,6 @@
namespace
{
// Slightly cheaper version for comparisons.
// Caller needs to be careful for very short distances (i.e. less than 1)
// or when accumuating the results i.e. (a + b)^2 != a^2 + b^2
//
float distanceSquared(ESM::Pathgrid::Point point, const osg::Vec3f& pos)
{
return (MWMechanics::PathFinder::MakeOsgVec3(point) - pos).length2();
}
// Return the closest pathgrid point index from the specified position co
// -ordinates. NOTE: Does not check if there is a sensible way to get there
// (e.g. a cliff in front).
//
// NOTE: pos is expected to be in local co-ordinates, as is grid->mPoints
//
int getClosestPoint(const ESM::Pathgrid* grid, const osg::Vec3f& pos)
{
assert(grid && !grid->mPoints.empty());
float distanceBetween = distanceSquared(grid->mPoints[0], pos);
int closestIndex = 0;
// TODO: if this full scan causes performance problems mapping pathgrid
// points to a quadtree may help
for(unsigned int counter = 1; counter < grid->mPoints.size(); counter++)
{
float potentialDistBetween = distanceSquared(grid->mPoints[counter], pos);
if(potentialDistBetween < distanceBetween)
{
distanceBetween = potentialDistBetween;
closestIndex = counter;
}
}
return closestIndex;
}
// Chooses a reachable end pathgrid point. start is assumed reachable.
std::pair<int, bool> getClosestReachablePoint(const ESM::Pathgrid* grid,
const MWWorld::CellStore *cell,
@ -62,7 +25,7 @@ namespace
// points to a quadtree may help
for(unsigned int counter = 0; counter < grid->mPoints.size(); counter++)
{
float potentialDistBetween = distanceSquared(grid->mPoints[counter], pos);
float potentialDistBetween = MWMechanics::PathFinder::DistanceSquared(grid->mPoints[counter], pos);
if (potentialDistBetween < closestDistanceReachable)
{
// found a closer one
@ -146,7 +109,7 @@ namespace MWMechanics
* pathgrid point (e.g. wander) then it may be worth while to call
* pop_back() to remove the redundant entry.
*
* NOTE: co-ordinates must be converted prior to calling getClosestPoint()
* NOTE: co-ordinates must be converted prior to calling GetClosestPoint()
*
* |
* | cell
@ -199,16 +162,16 @@ namespace MWMechanics
return;
}
// NOTE: getClosestPoint expects local co-ordinates
// NOTE: GetClosestPoint expects local co-ordinates
CoordinateConverter converter(mCell->getCell());
// NOTE: It is possible that getClosestPoint returns a pathgrind point index
// NOTE: It is possible that GetClosestPoint returns a pathgrind point index
// that is unreachable in some situations. e.g. actor is standing
// outside an area enclosed by walls, but there is a pathgrid
// point right behind the wall that is closer than any pathgrid
// point outside the wall
osg::Vec3f startPointInLocalCoords(converter.toLocalVec3(startPoint));
int startNode = getClosestPoint(mPathgrid, startPointInLocalCoords);
int startNode = GetClosestPoint(mPathgrid, startPointInLocalCoords);
osg::Vec3f endPointInLocalCoords(converter.toLocalVec3(endPoint));
std::pair<int, bool> endNode = getClosestReachablePoint(mPathgrid, cell,
@ -218,8 +181,8 @@ namespace MWMechanics
// if it's shorter for actor to travel from start to end, than to travel from either
// start or end to nearest pathgrid point, just travel from start to end.
float startToEndLength2 = (endPointInLocalCoords - startPointInLocalCoords).length2();
float endTolastNodeLength2 = distanceSquared(mPathgrid->mPoints[endNode.first], endPointInLocalCoords);
float startTo1stNodeLength2 = distanceSquared(mPathgrid->mPoints[startNode], startPointInLocalCoords);
float endTolastNodeLength2 = DistanceSquared(mPathgrid->mPoints[endNode.first], endPointInLocalCoords);
float startTo1stNodeLength2 = DistanceSquared(mPathgrid->mPoints[startNode], startPointInLocalCoords);
if ((startToEndLength2 < startTo1stNodeLength2) || (startToEndLength2 < endTolastNodeLength2))
{
mPath.push_back(endPoint);

@ -4,6 +4,7 @@
#include <components/esm/defs.hpp>
#include <components/esm/loadpgrd.hpp>
#include <list>
#include <cassert>
namespace MWWorld
{
@ -89,6 +90,43 @@ namespace MWMechanics
{
return osg::Vec3f(static_cast<float>(p.mX), static_cast<float>(p.mY), static_cast<float>(p.mZ));
}
// Slightly cheaper version for comparisons.
// Caller needs to be careful for very short distances (i.e. less than 1)
// or when accumuating the results i.e. (a + b)^2 != a^2 + b^2
//
static float DistanceSquared(ESM::Pathgrid::Point point, const osg::Vec3f& pos)
{
return (MWMechanics::PathFinder::MakeOsgVec3(point) - pos).length2();
}
// Return the closest pathgrid point index from the specified position co
// -ordinates. NOTE: Does not check if there is a sensible way to get there
// (e.g. a cliff in front).
//
// NOTE: pos is expected to be in local co-ordinates, as is grid->mPoints
//
static int GetClosestPoint(const ESM::Pathgrid* grid, const osg::Vec3f& pos)
{
assert(grid && !grid->mPoints.empty());
float distanceBetween = DistanceSquared(grid->mPoints[0], pos);
int closestIndex = 0;
// TODO: if this full scan causes performance problems mapping pathgrid
// points to a quadtree may help
for(unsigned int counter = 1; counter < grid->mPoints.size(); counter++)
{
float potentialDistBetween = DistanceSquared(grid->mPoints[counter], pos);
if(potentialDistBetween < distanceBetween)
{
distanceBetween = potentialDistBetween;
closestIndex = counter;
}
}
return closestIndex;
}
private:
void buildPath(const ESM::Pathgrid::Point &startPoint, const ESM::Pathgrid::Point &endPoint,

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