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- fixed: Due to the iteration limit of 100 in the path traverse code, running a trace was effectively limited to somewhere around 12800 map units. Also added the safer exit condition checks from the sight checking code to FPathTraverse.

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This commit is contained in:
Christoph Oelckers 2016-04-03 21:41:58 +02:00
parent 70b8afc5ec
commit 3f5e0c682e
2 changed files with 17 additions and 8 deletions
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21
src/p_maputl.cpp
View file

@ -1545,7 +1545,7 @@ void FPathTraverse::init(double x1, double y1, double x2, double y2, int flags,
// we want to use one list of checked actors for the entire operation // we want to use one list of checked actors for the entire operation
FBlockThingsIterator btit; FBlockThingsIterator btit;
for (count = 0 ; count < 100 ; count++) for (count = 0 ; count < 1000 ; count++)
{ {
if (flags & PT_ADDLINES) if (flags & PT_ADDLINES)
{ {
@ -1557,26 +1557,30 @@ void FPathTraverse::init(double x1, double y1, double x2, double y2, int flags,
AddThingIntercepts(mapx, mapy, btit, compatible); AddThingIntercepts(mapx, mapy, btit, compatible);
} }
if (mapx == xt2 && mapy == yt2) // both coordinates reached the end, so end the traversing.
{ if ((mapxstep | mapystep) == 0)
break; break;
}
// [RH] Handle corner cases properly instead of pretending they don't exist. // [RH] Handle corner cases properly instead of pretending they don't exist.
switch (((xs_FloorToInt(yintercept) == mapy) << 1) | (xs_FloorToInt(xintercept) == mapx)) switch (((xs_FloorToInt(yintercept) == mapy) << 1) | (xs_FloorToInt(xintercept) == mapx))
{ {
case 0: // neither xintercept nor yintercept match! case 0: // neither xintercept nor yintercept match!
count = 100; // Stop traversing, because somebody screwed up. count = 1000; // Stop traversing, because somebody screwed up.
break; break;
case 1: // xintercept matches case 1: // xintercept matches
xintercept += xstep; xintercept += xstep;
mapy += mapystep; mapy += mapystep;
if (mapy == mapey)
mapystep = 0;
break; break;
case 2: // yintercept matches case 2: // yintercept matches
yintercept += ystep; yintercept += ystep;
mapx += mapxstep; mapx += mapxstep;
if (mapx == mapex)
mapxstep = 0;
break; break;
case 3: // xintercept and yintercept both match case 3: // xintercept and yintercept both match
@ -1584,6 +1588,7 @@ void FPathTraverse::init(double x1, double y1, double x2, double y2, int flags,
// being entered need to be checked (which will happen when this loop // 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 // continues), but the other two blocks adjacent to the corner also need to
// be checked. // be checked.
// Since Doom.exe did not do this, this code won't either if run in compatibility mode.
if (!compatible) if (!compatible)
{ {
if (flags & PT_ADDLINES) if (flags & PT_ADDLINES)
@ -1601,10 +1606,14 @@ void FPathTraverse::init(double x1, double y1, double x2, double y2, int flags,
yintercept += ystep; yintercept += ystep;
mapx += mapxstep; mapx += mapxstep;
mapy += mapystep; mapy += mapystep;
if (mapx == mapex)
mapxstep = 0;
if (mapy == mapey)
mapystep = 0;
} }
else else
{ {
count = 100; // Doom originally did not handle this case so do the same in compatibility mode. count = 1000; // Doom originally did not handle this case so do the same in compatibility mode.
} }
break; break;
} }

4
src/p_sight.cpp
View file

@ -713,7 +713,7 @@ bool SightCheck::P_SightPathTraverse ()
// step through map blocks // step through map blocks
// Count is present to prevent a round off error from skipping the break // Count is present to prevent a round off error from skipping the break
for (count = 0 ; count < 100 ; count++) for (count = 0 ; count < 1000 ; count++)
{ {
// end traversing when reaching the end of the blockmap // 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. // an early out is not possible because with portals a trace can easily land outside the map's bounds.
@ -737,7 +737,7 @@ bool SightCheck::P_SightPathTraverse ()
case 0: // neither xintercept nor yintercept match! case 0: // neither xintercept nor yintercept match!
sightcounts[5]++; sightcounts[5]++;
// Continuing won't make things any better, so we might as well stop right here // Continuing won't make things any better, so we might as well stop right here
count = 100; count = 1000;
break; break;
case 1: // xintercept matches case 1: // xintercept matches