/*
* ====================
* =
* = P_TraverseIntercepts
* =
* = Returns true if the traverser function returns true for all lines
* ====================
*/
public static bool P_TraverseIntercepts(P_PathTraverse_delegate func, int maxfrac)
{
int count;
int dist;
p_local.intercept_t scan, in_;
count = intercept_p;
in_ = null; // shut up compiler warning
while ((count--) != 0)
{
dist = DoomDef.MAXINT;
for (int i = 0; i < intercept_p; ++i)
{
scan = intercepts[i];
if (scan.frac < dist)
{
dist = scan.frac;
in_ = scan;
}
}
if (dist > maxfrac)
{
return(true); // checked everything in range
}
if (!func.function(in_))
{
return(false); // don't bother going farther
}
in_.frac = DoomDef.MAXINT;
}
return(true); // everything was traversed
}
public static bool P_PathTraverse(int x1, int y1, int x2, int y2,
int flags, P_PathTraverse_delegate trav)
{
int xt1, yt1, xt2, yt2;
int xstep, ystep;
int partial;
int xintercept, yintercept;
int mapx, mapy, mapxstep, mapystep;
int count;
earlyout = (flags & p_local.PT_EARLYOUT) != 0;
r_main.validcount++;
intercept_p = 0;
if (((x1 - p_setup.bmaporgx) & (p_local.MAPBLOCKSIZE - 1)) == 0)
{
x1 += DoomDef.FRACUNIT; // don't side exactly on a line
}
if (((y1 - p_setup.bmaporgy) & (p_local.MAPBLOCKSIZE - 1)) == 0)
{
y1 += DoomDef.FRACUNIT; // don't side exactly on a line
}
trace.x = x1;
trace.y = y1;
trace.dx = x2 - x1;
trace.dy = y2 - y1;
x1 -= p_setup.bmaporgx;
y1 -= p_setup.bmaporgy;
xt1 = x1 >> p_local.MAPBLOCKSHIFT;
yt1 = y1 >> p_local.MAPBLOCKSHIFT;
x2 -= p_setup.bmaporgx;
y2 -= p_setup.bmaporgy;
xt2 = x2 >> p_local.MAPBLOCKSHIFT;
yt2 = y2 >> p_local.MAPBLOCKSHIFT;
if (xt2 > xt1)
{
mapxstep = 1;
partial = DoomDef.FRACUNIT - ((x1 >> p_local.MAPBTOFRAC) & (DoomDef.FRACUNIT - 1));
ystep = d_main.FixedDiv(y2 - y1, Math.Abs(x2 - x1));
}
else if (xt2 < xt1)
{
mapxstep = -1;
partial = (x1 >> p_local.MAPBTOFRAC) & (DoomDef.FRACUNIT - 1);
ystep = d_main.FixedDiv(y2 - y1, Math.Abs(x2 - x1));
}
else
{
mapxstep = 0;
partial = DoomDef.FRACUNIT;
ystep = 256 * DoomDef.FRACUNIT;
}
yintercept = (y1 >> p_local.MAPBTOFRAC) + DoomDef.FixedMul(partial, ystep);
if (yt2 > yt1)
{
mapystep = 1;
partial = DoomDef.FRACUNIT - ((y1 >> p_local.MAPBTOFRAC) & (DoomDef.FRACUNIT - 1));
xstep = d_main.FixedDiv(x2 - x1, Math.Abs(y2 - y1));
}
else if (yt2 < yt1)
{
mapystep = -1;
partial = (y1 >> p_local.MAPBTOFRAC) & (DoomDef.FRACUNIT - 1);
xstep = d_main.FixedDiv(x2 - x1, Math.Abs(y2 - y1));
}
else
{
mapystep = 0;
partial = DoomDef.FRACUNIT;
xstep = 256 * DoomDef.FRACUNIT;
}
xintercept = (x1 >> p_local.MAPBTOFRAC) + DoomDef.FixedMul(partial, xstep);
//
// step through map blocks
// Count is present to prevent a round off error from skipping the break
mapx = xt1;
mapy = yt1;
for (count = 0; count < 64; count++)
{
if ((flags & p_local.PT_ADDLINES) != 0)
{
if (!P_BlockLinesIterator(mapx, mapy, PIT_AddLineIntercepts))
{
return(false); // early out
}
}
if ((flags & p_local.PT_ADDTHINGS) != 0)
{
if (!P_BlockThingsIterator(mapx, mapy, PIT_AddThingIntercepts))
{
return(false); // early out
}
}
if (mapx == xt2 && mapy == yt2)
{
break;
}
if ((yintercept >> DoomDef.FRACBITS) == mapy)
{
yintercept += ystep;
mapx += mapxstep;
}
else if ((xintercept >> DoomDef.FRACBITS) == mapx)
{
xintercept += xstep;
mapy += mapystep;
}
}
//
// go through the sorted list
//
return(p_maputl.P_TraverseIntercepts(trav, DoomDef.FRACUNIT));
}
