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- some optimization of FPathTraverse:

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* we do not really need compatibility PointOnLineSide here. Unlike the movement code it'd only affect some extreme edge cases.
 * removed the special case for very short traces. This was a result of the original and very imprecise PointOnLine functions. Since those no longer get used here and floating point precision is a lot higher there is no need for this kind of treatment.
 * PointOnLine checks for the sides of an actor's bounding box don't need a full PointOnLineSide call, a simple coordinate comparison is fully sufficient, and this can easily be done in the existing switch/case block.
This commit is contained in:
Christoph Oelckers 2016-04-05 16:29:07 +02:00
parent ad13a55f0d
commit 04b0a13bd3
1 changed files with 45 additions and 125 deletions
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102
src/p_maputl.cpp
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@ -65,21 +65,6 @@ int P_AproxDistance (int dx, int dy)
return (dx < dy) ? dx+dy-(dx>>1) : dx+dy-(dy>>1);
}
//==========================================================================
//
// P_PointOnDivlineSideCompat
//
// Returns the fractional intercept point along the first divline
// with compatibility flag handling
//
//==========================================================================
inline int P_PointOnDivlineSideCompat(double x, double y, const divline_t *line)
{
return (i_compatflags2 & COMPATF2_POINTONLINE)
? P_VanillaPointOnDivlineSide(x, y, line) : P_PointOnDivlineSide(x, y, line);
}
//==========================================================================
//
// P_InterceptVector
@ -1168,20 +1153,8 @@ void FPathTraverse::AddLineIntercepts(int bx, int by)
double frac;
divline_t dl;
// avoid precision problems with two routines
if ( trace.dx > 16
|| trace.dy > 16
|| trace.dx < -16
|| trace.dy < -16)
{
s1 = P_PointOnDivlineSideCompat (ld->v1->fX(), ld->v1->fY(), &trace);
s2 = P_PointOnDivlineSideCompat (ld->v2->fX(), ld->v2->fY(), &trace);
}
else
{
s1 = P_PointOnLineSide (trace.x, trace.y, ld);
s2 = P_PointOnLineSide (trace.x+trace.dx, trace.y+trace.dy, ld);
}
s1 = P_PointOnDivlineSide (ld->v1->fX(), ld->v1->fY(), &trace);
s2 = P_PointOnDivlineSide (ld->v2->fX(), ld->v2->fY(), &trace);
if (s1 == s2) continue; // line isn't crossed
@ -1232,36 +1205,38 @@ void FPathTraverse::AddThingIntercepts (int bx, int by, FBlockThingsIterator &it
switch (i)
{
case 0: // Top edge
line.x = thing->X() + thing->radius;
line.y = thing->Y() + thing->radius;
if (trace.y < line.y) continue;
line.x = thing->X() + thing->radius;
line.dx = -thing->radius * 2;
line.dy = 0;
break;
case 1: // Right edge
line.x = thing->X() + thing->radius;
if (trace.x < line.x) continue;
line.y = thing->Y() - thing->radius;
line.dx = 0;
line.dy = thing->radius * 2;
break;
case 2: // Bottom edge
line.x = thing->X() - thing->radius;
line.y = thing->Y() - thing->radius;
if (trace.y > line.y) continue;
line.x = thing->X() - thing->radius;
line.dx = thing->radius * 2;
line.dy = 0;
break;
case 3: // Left edge
line.x = thing->X() - thing->radius;
if (trace.x > line.x) continue;
line.y = thing->Y() + thing->radius;
line.dx = 0;
line.dy = thing->radius * -2;
break;
}
// Check if this side is facing the trace origin
if (P_PointOnDivlineSide (trace.x, trace.y, &line) == 0)
{
numfronts++;
// If it is, see if the trace crosses it
@ -1305,8 +1280,7 @@ void FPathTraverse::AddThingIntercepts (int bx, int by, FBlockThingsIterator &it
newintercept.done = false;
newintercept.d.thing = thing;
intercepts.Push (newintercept);
continue;
}
break;
}
}
@ -1350,8 +1324,8 @@ void FPathTraverse::AddThingIntercepts (int bx, int by, FBlockThingsIterator &it
y2 = thing->Y() + thing->radius;
}
s1 = P_PointOnDivlineSideCompat (x1, y1, &trace);
s2 = P_PointOnDivlineSideCompat (x2, y2, &trace);
s1 = P_PointOnDivlineSide (x1, y1, &trace);
s2 = P_PointOnDivlineSide (x2, y2, &trace);
if (s1 != s2)
{
@ -1894,60 +1868,6 @@ int P_VanillaPointOnLineSide(double x, double y, const line_t* line)
return 1; // back side
}
//===========================================================================
//
// P_VanillaPointOnDivlineSide
// P_PointOnDivlineSideCompat() from the initial Doom source code release
//
//===========================================================================
int P_VanillaPointOnDivlineSide(double x, double y, const divline_t* line)
{
int dx;
int dy;
int left;
int right;
int ldx;
int ldy;
if (!line->dx)
{
if (x <= line->x)
return line->dy > 0;
return line->dy < 0;
}
if (!line->dy)
{
if (y <= line->y)
return line->dx < 0;
return line->dx > 0;
}
// This is supposed to be compatible so the rest needs to be done
// with the same broken fixed point checks as the original
dx = FloatToFixed(x - line->x);
dy = FloatToFixed(y - line->y);
ldx = FloatToFixed(line->dx);
ldy = FloatToFixed(line->dy);
// try to quickly decide by looking at sign bits
if ( (ldy ^ ldx ^ dx ^ dy)&0x80000000 )
{
if ( (ldy ^ dx) & 0x80000000 )
return 1; // (left is negative)
return 0;
}
left = MulScale16( ldy>>8, dx>>8 );
right = MulScale16( dy>>8 , ldx>>8 );
if (right < left)
return 0; // front side
return 1; // back side
}
//==========================================================================
//
// Use buggy PointOnSide and fix actors that lie on