/// <summary>
/// Find a target on the aiming line.
/// Sets LineTaget when a target is aimed at.
/// </summary>
public Fixed AimLineAttack(Mobj shooter, Angle angle, Fixed range)
{
currentShooter = shooter;
currentShooterZ = shooter.Z + (shooter.Height >> 1) + Fixed.FromInt(8);
currentRange = range;
var targetX = shooter.X + range.ToIntFloor() * Trig.Cos(angle);
var targetY = shooter.Y + range.ToIntFloor() * Trig.Sin(angle);
// Can't shoot outside view angles.
topSlope = Fixed.FromInt(100) / 160;
bottomSlope = Fixed.FromInt(-100) / 160;
lineTarget = null;
world.PathTraversal.PathTraverse(
shooter.X, shooter.Y,
targetX, targetY,
PathTraverseFlags.AddLines | PathTraverseFlags.AddThings,
aimTraverseFunc);
if (lineTarget != null)
{
return(currentAimSlope);
}
return(Fixed.Zero);
}
/// <summary>
/// Looks for special lines in front of the player to activate.
/// </summary>
public void UseLines(Player player)
{
var pt = world.PathTraversal;
useThing = player.Mobj;
var angle = player.Mobj.Angle;
var x1 = player.Mobj.X;
var y1 = player.Mobj.Y;
var x2 = x1 + useRange.ToIntFloor() * Trig.Cos(angle);
var y2 = y1 + useRange.ToIntFloor() * Trig.Sin(angle);
pt.PathTraverse(x1, y1, x2, y2, PathTraverseFlags.AddLines, useTraverseFunc);
}
/// <summary>
/// Fire a hitscan bullet.
/// If damage == 0, it is just a test trace that will leave linetarget set.
/// </summary>
public void LineAttack(Mobj shooter, Angle angle, Fixed range, Fixed slope, int damage)
{
currentShooter = shooter;
currentShooterZ = shooter.Z + (shooter.Height >> 1) + Fixed.FromInt(8);
currentRange = range;
currentAimSlope = slope;
currentDamage = damage;
var targetX = shooter.X + range.ToIntFloor() * Trig.Cos(angle);
var targetY = shooter.Y + range.ToIntFloor() * Trig.Sin(angle);
world.PathTraversal.PathTraverse(
shooter.X, shooter.Y,
targetX, targetY,
PathTraverseFlags.AddLines | PathTraverseFlags.AddThings,
shootTraverseFunc);
}
public bool PathTraverse(Fixed x1, Fixed y1, Fixed x2, Fixed y2, PathTraverseFlags flags, Func <Intercept, bool> trav)
{
earlyOut = (flags & PathTraverseFlags.EarlyOut) != 0;
var validCount = world.GetNewValidCount();
var bm = world.Map.BlockMap;
interceptCount = 0;
if (((x1 - bm.OriginX).Data & (BlockMap.MapBlockSize.Data - 1)) == 0)
{
// Don't side exactly on a line.
x1 += Fixed.One;
}
if (((y1 - bm.OriginY).Data & (BlockMap.MapBlockSize.Data - 1)) == 0)
{
// Don't side exactly on a line.
y1 += Fixed.One;
}
trace.X = x1;
trace.Y = y1;
trace.Dx = x2 - x1;
trace.Dy = y2 - y1;
x1 -= bm.OriginX;
y1 -= bm.OriginY;
var blockX1 = x1.Data >> BlockMap.MapBlockShift;
var blockY1 = y1.Data >> BlockMap.MapBlockShift;
x2 -= bm.OriginX;
y2 -= bm.OriginY;
var blockX2 = x2.Data >> BlockMap.MapBlockShift;
var blockY2 = y2.Data >> BlockMap.MapBlockShift;
Fixed stepX;
Fixed stepY;
Fixed partial;
int blockStepX;
int blockStepY;
if (blockX2 > blockX1)
{
blockStepX = 1;
partial = new Fixed(Fixed.FracUnit - ((x1.Data >> BlockMap.MapBToFrac) & (Fixed.FracUnit - 1)));
stepY = (y2 - y1) / Fixed.Abs(x2 - x1);
}
else if (blockX2 < blockX1)
{
blockStepX = -1;
partial = new Fixed((x1.Data >> BlockMap.MapBToFrac) & (Fixed.FracUnit - 1));
stepY = (y2 - y1) / Fixed.Abs(x2 - x1);
}
else
{
blockStepX = 0;
partial = Fixed.One;
stepY = Fixed.FromInt(256);
}
var interceptY = new Fixed(y1.Data >> BlockMap.MapBToFrac) + (partial * stepY);
if (blockY2 > blockY1)
{
blockStepY = 1;
partial = new Fixed(Fixed.FracUnit - ((y1.Data >> BlockMap.MapBToFrac) & (Fixed.FracUnit - 1)));
stepX = (x2 - x1) / Fixed.Abs(y2 - y1);
}
else if (blockY2 < blockY1)
{
blockStepY = -1;
partial = new Fixed((y1.Data >> BlockMap.MapBToFrac) & (Fixed.FracUnit - 1));
stepX = (x2 - x1) / Fixed.Abs(y2 - y1);
}
else
{
blockStepY = 0;
partial = Fixed.One;
stepX = Fixed.FromInt(256);
}
var interceptX = new Fixed(x1.Data >> BlockMap.MapBToFrac) + (partial * stepX);
// Step through map blocks.
// Count is present to prevent a round off error from skipping the break.
var bx = blockX1;
var by = blockY1;
for (var count = 0; count < 64; count++)
{
if ((flags & PathTraverseFlags.AddLines) != 0)
{
if (!bm.IterateLines(bx, by, lineInterceptFunc, validCount))
{
// Early out.
return(false);
}
}
if ((flags & PathTraverseFlags.AddThings) != 0)
{
if (!bm.IterateThings(bx, by, thingInterceptFunc))
{
// Early out.
return(false);
}
}
if (bx == blockX2 && by == blockY2)
{
break;
}
if ((interceptY.ToIntFloor()) == by)
{
interceptY += stepY;
bx += blockStepX;
}
else if ((interceptX.ToIntFloor()) == bx)
{
interceptX += stepX;
by += blockStepY;
}
}
// Go through the sorted list.
return(TraverseIntercepts(trav, Fixed.One));
}