/// <summary>
/// Returns true if the traverser function returns true for all lines.
/// </summary>
private bool TraverseIntercepts(Func <Intercept, bool> func, Fixed maxFrac)
{
var count = this.interceptCount;
Intercept intercept = null;
while (count-- > 0)
{
var dist = Fixed.MaxValue;
for (var i = 0; i < this.interceptCount; i++)
{
if (this.intercepts[i].Frac < dist)
{
dist = this.intercepts[i].Frac;
intercept = this.intercepts[i];
}
}
if (dist > maxFrac)
{
// Checked everything in range.
return(true);
}
if (!func(intercept))
{
// Don't bother going farther.
return(false);
}
intercept.Frac = Fixed.MaxValue;
}
// Everything was traversed.
return(true);
}
/// <summary>
/// Find a thing or wall which is on the aiming line.
/// Sets lineTaget and aimSlope when a target is aimed at.
/// </summary>
private bool AimTraverse(Intercept intercept)
{
if (intercept.Line != null)
{
var line = intercept.Line;
if ((line.Flags & LineFlags.TwoSided) == 0)
{
// Stop.
return(false);
}
var mc = this.world.MapCollision;
// Crosses a two sided line.
// A two sided line will restrict the possible target ranges.
mc.LineOpening(line);
if (mc.OpenBottom >= mc.OpenTop)
{
// Stop.
return(false);
}
var dist = this.currentRange * intercept.Frac;
if (line.FrontSector.FloorHeight != line.BackSector.FloorHeight)
{
var slope = (mc.OpenBottom - this.currentShooterZ) / dist;
if (slope > this.bottomSlope)
{
this.bottomSlope = slope;
}
}
if (line.FrontSector.CeilingHeight != line.BackSector.CeilingHeight)
{
var slope = (mc.OpenTop - this.currentShooterZ) / dist;
if (slope < this.topSlope)
{
this.topSlope = slope;
}
}
if (this.topSlope <= this.bottomSlope)
{
// Stop.
return(false);
}
// Shot continues.
return(true);
}
// Shoot a thing.
var thing = intercept.Thing;
if (thing == this.currentShooter)
{
// Can't shoot self.
return(true);
}
{
if ((thing.Flags & MobjFlags.Shootable) == 0)
{
// Corpse or something.
return(true);
}
// Check angles to see if the thing can be aimed at.
var dist = this.currentRange * intercept.Frac;
var thingTopSlope = (thing.Z + thing.Height - this.currentShooterZ) / dist;
if (thingTopSlope < this.bottomSlope)
{
// Shot over the thing.
return(true);
}
var thingBottomSlope = (thing.Z - this.currentShooterZ) / dist;
if (thingBottomSlope > this.topSlope)
{
// Shot under the thing.
return(true);
}
// This thing can be hit!
if (thingTopSlope > this.topSlope)
{
thingTopSlope = this.topSlope;
}
if (thingBottomSlope < this.bottomSlope)
{
thingBottomSlope = this.bottomSlope;
}
this.currentAimSlope = (thingTopSlope + thingBottomSlope) / 2;
this.lineTarget = thing;
// Don't go any farther.
return(false);
}
}
/// <summary>
/// Fire a hitscan bullet along the aiming line.
/// </summary>
private bool ShootTraverse(Intercept intercept)
{
var mi = this.world.MapInteraction;
var pt = this.world.PathTraversal;
if (intercept.Line != null)
{
var line = intercept.Line;
if (line.Special != 0)
{
mi.ShootSpecialLine(this.currentShooter, line);
}
if ((line.Flags & LineFlags.TwoSided) == 0)
{
goto hitLine;
}
var mc = this.world.MapCollision;
// Crosses a two sided line.
mc.LineOpening(line);
var dist = this.currentRange * intercept.Frac;
if (line.FrontSector.FloorHeight != line.BackSector.FloorHeight)
{
var slope = (mc.OpenBottom - this.currentShooterZ) / dist;
if (slope > this.currentAimSlope)
{
goto hitLine;
}
}
if (line.FrontSector.CeilingHeight != line.BackSector.CeilingHeight)
{
var slope = (mc.OpenTop - this.currentShooterZ) / dist;
if (slope < this.currentAimSlope)
{
goto hitLine;
}
}
// Shot continues.
return(true);
// Hit line.
hitLine:
// Position a bit closer.
var frac = intercept.Frac - Fixed.FromInt(4) / this.currentRange;
var x = pt.Trace.X + pt.Trace.Dx * frac;
var y = pt.Trace.Y + pt.Trace.Dy * frac;
var z = this.currentShooterZ + this.currentAimSlope * (frac * this.currentRange);
if (line.FrontSector.CeilingFlat == this.world.Map.SkyFlatNumber)
{
// Don't shoot the sky!
if (z > line.FrontSector.CeilingHeight)
{
return(false);
}
// It's a sky hack wall.
if (line.BackSector != null && line.BackSector.CeilingFlat == this.world.Map.SkyFlatNumber)
{
return(false);
}
}
// Spawn bullet puffs.
this.SpawnPuff(x, y, z);
// Don't go any farther.
return(false);
}
{
// Shoot a thing.
var thing = intercept.Thing;
if (thing == this.currentShooter)
{
// Can't shoot self.
return(true);
}
if ((thing.Flags & MobjFlags.Shootable) == 0)
{
// Corpse or something.
return(true);
}
// Check angles to see if the thing can be aimed at.
var dist = this.currentRange * intercept.Frac;
var thingTopSlope = (thing.Z + thing.Height - this.currentShooterZ) / dist;
if (thingTopSlope < this.currentAimSlope)
{
// Shot over the thing.
return(true);
}
var thingBottomSlope = (thing.Z - this.currentShooterZ) / dist;
if (thingBottomSlope > this.currentAimSlope)
{
// Shot under the thing.
return(true);
}
// Hit thing.
// Position a bit closer.
var frac = intercept.Frac - Fixed.FromInt(10) / this.currentRange;
var x = pt.Trace.X + pt.Trace.Dx * frac;
var y = pt.Trace.Y + pt.Trace.Dy * frac;
var z = this.currentShooterZ + this.currentAimSlope * (frac * this.currentRange);
// Spawn bullet puffs or blod spots, depending on target type.
if ((intercept.Thing.Flags & MobjFlags.NoBlood) != 0)
{
this.SpawnPuff(x, y, z);
}
else
{
this.SpawnBlood(x, y, z, this.currentDamage);
}
if (this.currentDamage != 0)
{
this.world.ThingInteraction.DamageMobj(thing, this.currentShooter, this.currentShooter, this.currentDamage);
}
// Don't go any farther.
return(false);
}
}
