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p_sight.cpp
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p_sight.cpp
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//-----------------------------------------------------------------------------
//
// Copyright 1993-1994 id Software
// Copyright 1994-1996 Raven Software
// Copyright 1999-2016 Randy Heit
// Copyright 2002-2016 Christoph Oelckers
//
// 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 3 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, see http://www.gnu.org/licenses/
//
//-----------------------------------------------------------------------------
//
#include <assert.h>
#include "doomdef.h"
#include "p_local.h"
#include "p_maputl.h"
#include "p_blockmap.h"
#include "m_random.h"
#include "p_lnspec.h"
#include "po_man.h"
#include "b_bot.h"
#include "p_spec.h"
#include "vm.h"
#include "g_levellocals.h"
#include "actorinlines.h"
static FRandom pr_botchecksight ("BotCheckSight");
static FRandom pr_checksight ("CheckSight");
/*
==============================================================================
P_CheckSight
This uses specialized forms of the maputils routines for optimized performance
==============================================================================
*/
// Performance meters
static int sightcounts[6];
static cycle_t SightCycles;
static cycle_t MaxSightCycles;
enum
{
SO_TOPFRONT = 1,
SO_TOPBACK = 2,
SO_BOTTOMFRONT = 4,
SO_BOTTOMBACK = 8,
};
struct SightOpening
{
double top;
double bottom;
int range;
int portalflags;
void SwapSides()
{
portalflags = ((portalflags & (SO_TOPFRONT | SO_BOTTOMFRONT)) << 1) | ((portalflags & (SO_TOPBACK | SO_BOTTOMBACK)) >> 1);
}
};
struct SightTask
{
double Frac;
double topslope;
double bottomslope;
int direction;
int portalgroup;
};
static TArray<intercept_t> intercepts (128);
static TArray<SightTask> portals(32);
class SightCheck
{
FLevelLocals *Level;
DVector3 sightstart;
DVector2 sightend;
double Startfrac;
AActor * seeingthing;
double Lastztop; // z at last line
double Lastzbottom; // z at last line
sector_t * lastsector; // last sector being entered by trace
double topslope, bottomslope; // slopes to top and bottom of target
int Flags;
divline_t Trace;
int portaldir;
int portalgroup;
bool portalfound;
unsigned int myseethrough;
void P_SightOpening(SightOpening &open, const line_t *linedef, double x, double y);
bool PTR_SightTraverse (intercept_t *in);
bool P_SightCheckLine (line_t *ld);
int P_SightBlockLinesIterator (int x, int y);
bool P_SightTraverseIntercepts ();
bool LineBlocksSight(line_t *ld);
public:
SightCheck(FLevelLocals *l)
{
Level = l;
}
bool P_SightPathTraverse ();
void init(AActor * t1, AActor * t2, sector_t *startsector, SightTask *task, int flags)
{
sightstart = t1->PosRelative(task->portalgroup);
sightend = t2->PosRelative(task->portalgroup);
sightstart.Z += t1->Height * 0.75;
portalgroup = task->portalgroup;
Startfrac = task->Frac;
Trace = { sightstart.X, sightstart.Y, sightend.X - sightstart.X, sightend.Y - sightstart.Y };
Lastztop = Lastzbottom = sightstart.Z;
lastsector = startsector;
seeingthing=t2;
topslope = task->topslope;
bottomslope = task->bottomslope;
Flags = flags;
portaldir = task->direction;
portalfound = false;
myseethrough = FF_SEETHROUGH;
}
};
//==========================================================================
//
// P_SightOpening
//
// Simplified version that removes everything not needed for a sight check
//
//==========================================================================
void SightCheck::P_SightOpening(SightOpening &open, const line_t *linedef, double x, double y)
{
open.portalflags = 0;
open.bottom = open.top = 0;
sector_t *front = linedef->frontsector;
sector_t *back = linedef->backsector;
if (back == NULL)
{
// single sided line
if (linedef->flags & ML_PORTALCONNECT)
{
if (!front->PortalBlocksSight(sector_t::ceiling)) open.top = LINEOPEN_MAX, open.portalflags |= SO_TOPFRONT;
if (!front->PortalBlocksSight(sector_t::floor)) open.bottom = LINEOPEN_MIN, open.portalflags |= SO_BOTTOMFRONT;
if (open.top == 0) open.top = front->floorplane.ZatPoint(x, y);
if (open.bottom == 0) open.bottom = front->ceilingplane.ZatPoint(x, y);
}
open.range = 0;
return;
}
double fc = 0, ff = 0, bc = 0, bf = 0;
if (linedef->flags & ML_PORTALCONNECT)
{
if (!front->PortalBlocksSight(sector_t::ceiling)) fc = LINEOPEN_MAX, open.portalflags |= SO_TOPFRONT;
if (!back->PortalBlocksSight(sector_t::ceiling)) bc = LINEOPEN_MAX, open.portalflags |= SO_TOPBACK;
if (!front->PortalBlocksSight(sector_t::floor)) ff = LINEOPEN_MIN, open.portalflags |= SO_BOTTOMFRONT;
if (!back->PortalBlocksSight(sector_t::floor)) bf = LINEOPEN_MIN, open.portalflags |= SO_BOTTOMBACK;
}
if (fc == 0) fc = front->ceilingplane.ZatPoint(x, y);
if (bc == 0) bc = back->ceilingplane.ZatPoint(x, y);
if (ff == 0) ff = front->floorplane.ZatPoint(x, y);
if (bf == 0) bf = back->floorplane.ZatPoint(x, y);
open.bottom = MAX(ff, bf);
open.top = MIN(fc, bc);
// we only want to know if there is an opening, not how large it is.
open.range = open.bottom < open.top;
}
/*
==============
=
= PTR_SightTraverse
=
==============
*/
bool SightCheck::PTR_SightTraverse (intercept_t *in)
{
line_t *li;
double slope;
SightOpening open;
int frontflag = -1;
li = in->d.line;
//
// crosses a two sided line
//
// ignore self referencing sectors if COMPAT_TRACE is on
if ((Level->i_compatflags & COMPATF_TRACE) && li->frontsector == li->backsector)
return true;
double trX = Trace.x + Trace.dx * in->frac;
double trY = Trace.y + Trace.dy * in->frac;
P_SightOpening(open, li, trX, trY);
if (LineBlocksSight(in->d.line))
{
// This may not skip P_SightOpening, but only reduce the open range to 0.
open.range = 0;
if (open.bottom != LINEOPEN_MIN) open.bottom = open.top;
}
FLinePortal *lport = li->getPortal();
if (open.range == 0 && open.portalflags == 0 && (lport == nullptr || lport->mType != PORTT_LINKED)) // quick test for totally closed doors (must be delayed if portal checks are needed, though)
return false; // stop
if (in->frac == 0)
return true;
// check bottom
if (open.bottom > LINEOPEN_MIN)
{
slope = (open.bottom - sightstart.Z) / in->frac;
if (slope > bottomslope)
bottomslope = slope;
}
// check top
if (open.top < LINEOPEN_MAX)
{
slope = (open.top - sightstart.Z) / in->frac;
if (slope < topslope)
topslope = slope;
}
if (open.portalflags)
{
sector_t *frontsec, *backsec;
frontflag = P_PointOnLineSidePrecise(sightstart, li);
if (!frontflag)
{
frontsec = li->frontsector;
backsec = li->backsector;
}
else
{
frontsec = li->backsector;
if (!frontsec) return false; // We are looking through the backside of a one-sided line. Just abort if that happens.
backsec = li->frontsector;
open.SwapSides(); // swap flags to make the next checks simpler.
}
if (portaldir != sector_t::floor && (open.portalflags & SO_TOPBACK) && !(open.portalflags & SO_TOPFRONT))
{
portals.Push({ in->frac, topslope, bottomslope, sector_t::ceiling, backsec->GetOppositePortalGroup(sector_t::ceiling) });
}
if (portaldir != sector_t::ceiling && (open.portalflags & SO_BOTTOMBACK) && !(open.portalflags & SO_BOTTOMFRONT))
{
portals.Push({ in->frac, topslope, bottomslope, sector_t::floor, backsec->GetOppositePortalGroup(sector_t::floor) });
}
}
if (lport != nullptr && lport->mDestination != nullptr)
{
portals.Push({ in->frac, topslope, bottomslope, portaldir, lport->mDestination->frontsector->PortalGroup });
return false;
}
if (topslope <= bottomslope || open.range == 0)
return false; // stop
// now handle 3D-floors
if(li->frontsector->e->XFloor.ffloors.Size() || li->backsector->e->XFloor.ffloors.Size())
{
if (frontflag == -1) frontflag = P_PointOnLineSidePrecise(sightstart, li);
//Check 3D FLOORS!
for(int i=1;i<=2;i++)
{
sector_t * s=i==1? li->frontsector:li->backsector;
double highslope, lowslope;
double topz= topslope * in->frac + sightstart.Z;
double bottomz= bottomslope * in->frac + sightstart.Z;
for (auto rover : s->e->XFloor.ffloors)
{
if ((rover->flags & FF_SEETHROUGH) == myseethrough || !(rover->flags & FF_EXISTS)) continue;
if ((Flags & SF_IGNOREWATERBOUNDARY) && (rover->flags & FF_SOLID) == 0) continue;
double ff_bottom = rover->bottom.plane->ZatPoint(trX, trY);
double ff_top = rover->top.plane->ZatPoint(trX, trY);
highslope = (ff_top - sightstart.Z) / in->frac;
lowslope = (ff_bottom - sightstart.Z) / in->frac;
if (highslope >= topslope)
{
// blocks completely
if (lowslope <= bottomslope) return false;
// blocks upper edge of view
if (lowslope < topslope) topslope = lowslope;
}
else if (lowslope <= bottomslope)
{
// blocks lower edge of view
if (highslope > bottomslope) bottomslope = highslope;
}
else
{
// the 3D-floor is inside the viewing cone but neither clips the top nor the bottom so by
// itself it can't be view blocking.
// However, if there's a 3D-floor on the other side that obstructs the same vertical range
// the 2 together will block sight.
sector_t * sb = i == 2 ? li->frontsector : li->backsector;
for (auto rover2 : sb->e->XFloor.ffloors)
{
if ((rover2->flags & FF_SEETHROUGH) == myseethrough || !(rover2->flags & FF_EXISTS)) continue;
if ((Flags & SF_IGNOREWATERBOUNDARY) && (rover->flags & FF_SOLID) == 0) continue;
double ffb_bottom = rover2->bottom.plane->ZatPoint(trX, trY);
double ffb_top = rover2->top.plane->ZatPoint(trX, trY);
if ((ffb_bottom >= ff_bottom && ffb_bottom <= ff_top) ||
(ffb_top <= ff_top && ffb_top >= ff_bottom) ||
(ffb_top >= ff_top && ffb_bottom <= ff_bottom) ||
(ffb_top <= ff_top && ffb_bottom >= ff_bottom))
{
return false;
}
}
}
// trace is leaving a sector with a 3d-floor
if (s == lastsector && frontflag == i - 1)
{
// upper slope intersects with this 3d-floor
if (Lastztop <= ff_bottom && topz > ff_top)
{
topslope = lowslope;
}
// lower slope intersects with this 3d-floor
if (Lastzbottom >= ff_top && bottomz < ff_top)
{
bottomslope = highslope;
}
}
if (topslope <= bottomslope) return false; // stop
}
}
lastsector = frontflag==0 ? li->backsector : li->frontsector;
}
else lastsector=NULL; // don't need it if there are no 3D-floors
Lastztop = (topslope * in->frac) + sightstart.Z;
Lastzbottom = (bottomslope * in->frac) + sightstart.Z;
return true; // keep going
}
// performs trivial visibility checks.
bool SightCheck::LineBlocksSight(line_t *ld)
{
// try to early out the check
if (!ld->backsector || !(ld->flags & ML_TWOSIDED) || (ld->flags & ML_BLOCKSIGHT))
return true; // stop checking
// [RH] don't see past block everything lines
if (ld->flags & ML_BLOCKEVERYTHING)
{
if (!(Flags & SF_SEEPASTBLOCKEVERYTHING))
{
return true;
}
// Pretend the other side is invisible if this is not an impact line
// that runs a script on the current map. Used to prevent monsters
// from trying to attack through a block everything line unless
// there's a chance their attack will make it nonblocking.
if (!(Flags & SF_SEEPASTSHOOTABLELINES))
{
if (!(ld->activation & SPAC_Impact))
{
return true;
}
if (ld->special != ACS_Execute && ld->special != ACS_ExecuteAlways)
{
return true;
}
if (ld->args[1] != 0 && ld->args[1] != Level->levelnum)
{
return true;
}
}
}
return false;
}
/*
==================
=
= P_SightCheckLine
=
===================
*/
bool SightCheck::P_SightCheckLine (line_t *ld)
{
divline_t dl;
if (ld->validcount == validcount)
{
return true;
}
ld->validcount = validcount;
if (P_PointOnDivlineSide (ld->v1->fPos(), &Trace) ==
P_PointOnDivlineSide (ld->v2->fPos(), &Trace))
{
return true; // line isn't crossed
}
P_MakeDivline (ld, &dl);
if (P_PointOnDivlineSide (Trace.x, Trace.y, &dl) ==
P_PointOnDivlineSide (Trace.x+Trace.dx, Trace.y+Trace.dy, &dl))
{
return true; // line isn't crossed
}
if (!portalfound) // when portals come into play, the quick-outs here may not be performed
{
if (LineBlocksSight(ld)) return false;
}
sightcounts[3]++;
// store the line for later intersection testing
intercept_t newintercept;
newintercept.isaline = true;
newintercept.d.line = ld;
intercepts.Push (newintercept);
return true;
}
/*
==================
=
= P_SightBlockLinesIterator
=
===================
*/
int SightCheck::P_SightBlockLinesIterator (int x, int y)
{
int offset;
int *list;
int res = 1;
polyblock_t *polyLink;
unsigned int i;
offset = y* Level->blockmap.bmapwidth+x;
// if any of the previous blocks may contain a portal we may abort the collection of lines here, but we may not abort the sight check.
// (We still try to delay activating this for as long as possible.)
portalfound = portalfound || Level->PortalBlockmap(x, y).containsLinkedPortals;
polyLink = Level->PolyBlockMap[offset];
portalfound |= (polyLink && Level->PortalBlockmap.hasLinkedPolyPortals);
while (polyLink)
{
if (polyLink->polyobj)
{ // only check non-empty links
if (polyLink->polyobj->validcount != validcount)
{
polyLink->polyobj->validcount = validcount;
for (i = 0; i < polyLink->polyobj->Linedefs.Size(); i++)
{
if (!P_SightCheckLine(polyLink->polyobj->Linedefs[i]))
{
if (!portalfound) return 0;
else res = -1;
}
}
}
}
polyLink = polyLink->next;
}
for (list = Level->blockmap.GetLines(x, y); *list != -1; list++)
{
if (!P_SightCheckLine (&Level->lines[*list]))
{
if (!portalfound) return 0;
else res = -1;
}
}
return res; // everything was checked
}
/*
====================
=
= P_SightTraverseIntercepts
=
= Returns true if the traverser function returns true for all lines
====================
*/
bool SightCheck::P_SightTraverseIntercepts ()
{
unsigned count;
double dist;
intercept_t *scan, *in;
unsigned scanpos;
divline_t dl;
count = intercepts.Size ();
//
// calculate intercept distance
//
for (scanpos = 0; scanpos < intercepts.Size (); scanpos++)
{
scan = &intercepts[scanpos];
P_MakeDivline (scan->d.line, &dl);
scan->frac = P_InterceptVector (&Trace, &dl);
if (scan->frac < Startfrac)
{
scan->frac = INT_MAX;
count--;
}
}
//
// go through in order
// proper order is needed to handle 3D floors and portals.
//
in = NULL;
while (count--)
{
dist = INT_MAX;
for (scanpos = 0; scanpos < intercepts.Size (); scanpos++)
{
scan = &intercepts[scanpos];
if (scan->frac < dist)
{
dist = scan->frac;
in = scan;
}
}
if (in != NULL)
{
if (!PTR_SightTraverse (in))
return false; // don't bother going farther
in->frac = INT_MAX;
}
}
if (lastsector == seeingthing->Sector && lastsector->e->XFloor.ffloors.Size())
{
// we must do one last check whether the trace has crossed a 3D floor in the last sector
double topz = topslope + sightstart.Z;
double bottomz = bottomslope + sightstart.Z;
for (auto rover : lastsector->e->XFloor.ffloors)
{
if ((rover->flags & FF_SEETHROUGH) == myseethrough || !(rover->flags & FF_EXISTS)) continue;
if ((Flags & SF_IGNOREWATERBOUNDARY) && (rover->flags & FF_SOLID) == 0) continue;
double ff_bottom = rover->bottom.plane->ZatPoint(seeingthing);
double ff_top = rover->top.plane->ZatPoint(seeingthing);
if (Lastztop <= ff_bottom && topz > ff_bottom && Lastzbottom <= ff_bottom && bottomz > ff_bottom) return false;
if (Lastzbottom >= ff_top && bottomz < ff_top && Lastztop >= ff_top && topz < ff_top) return false;
}
}
return true; // everything was traversed
}
/*
==================
=
= P_SightPathTraverse
=
= Traces a line from x1,y1 to x2,y2, calling the traverser function for each block
= Returns true if the traverser function returns true for all lines
==================
*/
bool SightCheck::P_SightPathTraverse ()
{
double x1, x2, y1, y2;
double xt1,yt1,xt2,yt2;
double xstep,ystep;
double partialx, partialy;
double xintercept, yintercept;
int mapx, mapy, mapxstep, mapystep;
int count;
validcount++;
intercepts.Clear ();
x1 = sightstart.X + Startfrac * Trace.dx;
y1 = sightstart.Y + Startfrac * Trace.dy;
x2 = sightend.X;
y2 = sightend.Y;
if (lastsector == NULL) lastsector = Level->PointInSector(x1, y1);
// for FF_SEETHROUGH the following rule applies:
// If the viewer is in an area without FF_SEETHROUGH he can only see into areas without this flag
// If the viewer is in an area with FF_SEETHROUGH he can only see into areas with this flag
bool checkfloor = true, checkceiling = true;
for(auto rover : lastsector->e->XFloor.ffloors)
{
if(!(rover->flags & FF_EXISTS)) continue;
if ((Flags & SF_IGNOREWATERBOUNDARY) && (rover->flags & FF_SOLID) == 0) continue;
double ff_bottom=rover->bottom.plane->ZatPoint(sightstart);
double ff_top=rover->top.plane->ZatPoint(sightstart);
if (sightstart.Z < ff_top) checkceiling = false;
if (sightstart.Z >= ff_bottom) checkfloor = false;
if (sightstart.Z < ff_top && sightstart.Z >= ff_bottom)
{
myseethrough = rover->flags & FF_SEETHROUGH;
break;
}
}
// We also must check if the starting sector contains portals, and start sight checks in those as well.
if (portaldir != sector_t::floor && checkceiling && !lastsector->PortalBlocksSight(sector_t::ceiling))
{
portals.Push({ 0, topslope, bottomslope, sector_t::ceiling, lastsector->GetOppositePortalGroup(sector_t::ceiling) });
}
if (portaldir != sector_t::ceiling && checkfloor && !lastsector->PortalBlocksSight(sector_t::floor))
{
portals.Push({ 0, topslope, bottomslope, sector_t::floor, lastsector->GetOppositePortalGroup(sector_t::floor) });
}
x1 -= Level->blockmap.bmaporgx;
y1 -= Level->blockmap.bmaporgy;
xt1 = x1 / FBlockmap::MAPBLOCKUNITS;
yt1 = y1 / FBlockmap::MAPBLOCKUNITS;
x2 -= Level->blockmap.bmaporgx;
y2 -= Level->blockmap.bmaporgy;
xt2 = x2 / FBlockmap::MAPBLOCKUNITS;
yt2 = y2 / FBlockmap::MAPBLOCKUNITS;
mapx = xs_FloorToInt(xt1);
mapy = xs_FloorToInt(yt1);
int mapex = xs_FloorToInt(xt2);
int mapey = xs_FloorToInt(yt2);
if (mapex > mapx)
{
mapxstep = 1;
partialx = 1. - xt1 + xs_FloorToInt(xt1);
ystep = (y2 - y1) / fabs(x2 - x1);
}
else if (mapex < mapx)
{
mapxstep = -1;
partialx = xt1 - xs_FloorToInt(xt1);
ystep = (y2 - y1) / fabs(x2 - x1);
}
else
{
mapxstep = 0;
partialx = 1.;
ystep = 256;
}
yintercept = yt1 + partialx * ystep;
if (mapey > mapy)
{
mapystep = 1;
partialy = 1. - yt1 + xs_FloorToInt(yt1);
xstep = (x2 - x1) / fabs(y2 - y1);
}
else if (mapey < mapy)
{
mapystep = -1;
partialy = yt1 - xs_FloorToInt(yt1);
xstep = (x2 - x1) / fabs(y2 - y1);
}
else
{
mapystep = 0;
partialy = 1;
xstep = 256;
}
xintercept = xt1 + partialy * xstep;
// [RH] Fix for traces that pass only through blockmap corners. In that case,
// xintercept and yintercept can both be set ahead of mapx and mapy, so the
// for loop would never advance anywhere.
if (fabs(xstep) == 1. && fabs(ystep) == 1.)
{
if (ystep < 0)
{
partialx = 1. - partialx;
}
if (xstep < 0)
{
partialy = 1. - partialy;
}
if (partialx == partialy)
{
xintercept = xt1;
yintercept = yt1;
}
}
//
// step through map blocks
// Count is present to prevent a round off error from skipping the break
int itres = -1;
for (count = 0 ; count < 1000 ; count++)
{
// end traversing when reaching the end of the blockmap
// an early out is not possible because with portals a trace can easily land outside the map's bounds.
if (!Level->blockmap.isValidBlock(mapx, mapy))
{
break;
}
itres = P_SightBlockLinesIterator(mapx, mapy);
if (itres == 0)
{
sightcounts[1]++;
return false; // early out
}
// either reached the end or had an early-out condition with portals left to check,
if (itres == -1 || (mapxstep | mapystep) == 0)
break;
switch (((xs_FloorToInt(yintercept) == mapy) << 1) | (xs_FloorToInt(xintercept) == mapx))
{
case 0: // neither xintercept nor yintercept match!
sightcounts[5]++;
// Continuing won't make things any better, so we might as well stop right here
count = 1000;
break;
case 1: // xintercept matches
xintercept += xstep;
mapy += mapystep;
if (mapy == mapey)
mapystep = 0;
break;
case 2: // yintercept matches
yintercept += ystep;
mapx += mapxstep;
if (mapx == mapex)
mapxstep = 0;
break;
case 3: // xintercept and yintercept both match
sightcounts[4]++;
// The trace is exiting a block through its corner. Not only does the block
// being entered need to be checked (which will happen when this loop
// continues), but the other two blocks adjacent to the corner also need to
// be checked.
if (!P_SightBlockLinesIterator (mapx + mapxstep, mapy) ||
!P_SightBlockLinesIterator (mapx, mapy + mapystep))
{
sightcounts[1]++;
return false;
}
xintercept += xstep;
yintercept += ystep;
mapx += mapxstep;
mapy += mapystep;
if (mapx == mapex)
mapxstep = 0;
if (mapy == mapey)
mapystep = 0;
break;
}
}
//
// couldn't early out, so go through the sorted list
//
sightcounts[2]++;
bool traverseres = P_SightTraverseIntercepts ( );
if (itres == -1) return false; // if the iterator had an early out there was no line of sight. The traverser was only called to collect more portals.
if (seeingthing->Sector->PortalGroup != portalgroup) return false; // We are in a different group than the seeingthing, so this trace cannot determine visibility alone.
return traverseres;
}
/*
=====================
=
= P_CheckSight
=
= Returns true if a straight line between t1 and t2 is unobstructed
= look from eyes of t1 to any part of t2
=
= killough 4/20/98: cleaned up, made to use new LOS struct
=
=====================
*/
int P_CheckSight (AActor *t1, AActor *t2, int flags)
{
SightCycles.Clock();
bool res;
if (t1 == nullptr || t2 == nullptr)
{
return false;
}
auto s1 = t1->Sector;
auto s2 = t2->Sector;
//
// check for trivial rejection
//
if (!t1->Level->CheckReject(s1, s2))
{
sightcounts[0]++;
res = false; // can't possibly be connected
goto done;
}
//
// check precisely
//
// [RH] Andy Baker's stealth monsters:
// Cannot see an invisible object
if ((flags & SF_IGNOREVISIBILITY) == 0 && ((t2->renderflags & RF_INVISIBLE) || !t2->RenderStyle.IsVisible(t2->Alpha)))
{ // small chance of an attack being made anyway
if ((t1->Level->BotInfo.m_Thinking ? pr_botchecksight() : pr_checksight()) > 50)
{
res = false;
goto done;
}
}
// killough 4/19/98: make fake floors and ceilings block monster view
if (!(flags & SF_IGNOREWATERBOUNDARY))
{
if ((s1->GetHeightSec() &&
((t1->Top() <= s1->heightsec->floorplane.ZatPoint(t1) &&
t2->Z() >= s1->heightsec->floorplane.ZatPoint(t2)) ||
(t1->Z() >= s1->heightsec->ceilingplane.ZatPoint(t1) &&
t2->Top() <= s1->heightsec->ceilingplane.ZatPoint(t2))))
||
(s2->GetHeightSec() &&
((t2->Top() <= s2->heightsec->floorplane.ZatPoint(t2) &&
t1->Z() >= s2->heightsec->floorplane.ZatPoint(t1)) ||
(t2->Z() >= s2->heightsec->ceilingplane.ZatPoint(t2) &&
t1->Top() <= s2->heightsec->ceilingplane.ZatPoint(t1)))))
{
res = false;
goto done;
}
}
// An unobstructed LOS is possible.
// Now look from eyes of t1 to any part of t2.
validcount++;
portals.Clear();
{
sector_t *sec;
double lookheight = t1->Z() + t1->Height*0.75;
t1->GetPortalTransition(lookheight, &sec);
double bottomslope = t2->Z() - lookheight;
double topslope = bottomslope + t2->Height;
SightTask task = { 0, topslope, bottomslope, -1, sec->PortalGroup };
SightCheck s(t1->Level);
s.init(t1, t2, sec, &task, flags);
res = s.P_SightPathTraverse ();
if (!res)
{
double dist = t1->Distance2D(t2);
for (unsigned i = 0; i < portals.Size(); i++)
{
portals[i].Frac += 1 / dist;
s.init(t1, t2, NULL, &portals[i], flags);
if (s.P_SightPathTraverse())
{
res = true;
break;
}
}
}
}
done:
SightCycles.Unclock();
return res;
}
ADD_STAT (sight)
{
FString out;
out.Format ("%04.1f ms (%04.1f max), %5d %2d%4d%4d%4d%4d\n",
SightCycles.TimeMS(), MaxSightCycles.TimeMS(),
sightcounts[3], sightcounts[0], sightcounts[1], sightcounts[2], sightcounts[4], sightcounts[5]);
return out;
}
void P_ResetSightCounters (bool full)
{
if (full)
{
MaxSightCycles.Reset();
}
if (SightCycles.Time() > MaxSightCycles.Time())
{
MaxSightCycles = SightCycles;
}
SightCycles.Reset();
memset (sightcounts, 0, sizeof(sightcounts));
}