func distFromPointToSeg(p linear.Vec2, s linear.Seg2) float64 {
s.P = s.P.Sub(p)
s.Q = s.Q.Sub(p)
cross := s.Ray().Cross()
crossSeg := linear.Seg2{Q: cross}
if crossSeg.Left(s.P) != crossSeg.Left(s.Q) {
return s.DistFromOrigin()
}
da := s.P.Mag()
db := s.Q.Mag()
if da < db {
return da
}
return db
}
func (b *BaseEnt) Think(g *Game) {
// This will clear out old conditions
b.StatsInst.Think()
var dead []int
// Calling DoOrdered is too slow, so we just sort the Gids ourselves and go
// through them in order.
pids := make([]int, len(b.Processes))[0:0]
for pid := range b.Processes {
pids = append(pids, pid)
}
sort.Ints(pids)
for _, pid := range pids {
proc := b.Processes[pid]
proc.Think(g)
if proc.Dead() {
dead = append(dead, pid)
} else {
b.StatsInst.ApplyCondition(proc)
}
}
// Removed dead processes from the ent
for _, id := range dead {
delete(b.Processes, id)
}
if b.Delta.Speed < -1.0 {
b.Delta.Speed = -1.0
}
if b.Delta.Speed > 1.0 {
b.Delta.Speed = 1.0
}
// TODO: Speed is a complete misnomer now - fix it!
force := b.Delta.Speed * (linear.Vec2{1, 0}).Rotate(b.Target.Angle).Dot((linear.Vec2{1, 0}).Rotate(b.Angle_))
b.ApplyForce((linear.Vec2{1, 0}).Rotate(b.Angle_).Scale(force * b.Stats().MaxAcc()))
mangle := math.Atan2(b.Velocity.Y, b.Velocity.X)
friction := g.Friction
b.Velocity = b.Velocity.Scale(
math.Pow(friction, 1+3*math.Abs(math.Sin(b.Angle_-mangle))))
if b.Velocity.Mag2() < 0.01 {
b.Velocity = linear.Vec2{0, 0}
} else {
size := b.Stats().Size()
sizeSq := size * size
// We pretend that the player is started from a little behind wherever they
// actually are. This makes it a lot easier to get collisions to make sense
// from frame to frame.
epsilon := b.Velocity.Norm().Scale(size / 2)
move := linear.Seg2{b.Position.Sub(epsilon), b.Position.Add(b.Velocity)}
prev := b.Position
walls := g.local.temp.WallCache.GetWalls(int(b.Position.X), int(b.Position.Y))
for _, wall := range walls {
// Don't bother with back-facing segments
if wall.Right(b.Position) {
continue
}
// Check against the segment itself
if wall.Ray().Cross().Dot(move.Ray()) <= 0 {
shiftNorm := wall.Ray().Cross().Norm()
shift := shiftNorm.Scale(size)
col := linear.Seg2{shift.Add(wall.P), shift.Add(wall.Q)}
if move.DoesIsect(col) {
cross := col.Ray().Cross()
fix := linear.Seg2{move.Q, cross.Add(move.Q)}
isect := fix.Isect(col)
move.Q = isect
}
}
}
for _, wall := range walls {
// Check against the leading vertex
{
v := wall.P
originMove := linear.Seg2{move.P.Sub(v), move.Q.Sub(v)}
originPerp := linear.Seg2{linear.Vec2{}, move.Ray().Cross()}
dist := originMove.DistFromOrigin()
if originPerp.DoesIsect(originMove) && dist < size {
// Stop passthrough
isect := originMove.Isect(originPerp).Add(v)
diff := math.Sqrt(sizeSq - dist*dist)
finalLength := isect.Sub(move.P).Mag() - diff
move.Q = move.Ray().Norm().Scale(finalLength).Add(move.P)
} else if v.Sub(move.Q).Mag2() < sizeSq {
move.Q = move.Q.Sub(v).Norm().Scale(size).Add(v)
}
}
}
b.Position = move.Q
b.Velocity = b.Position.Sub(prev)
}
if math.Abs(b.Angle_+b.Target.Angle-math.Pi) < 0.01 {
b.Angle_ += 0.1
} else {
frac := 0.80
curDir := (linear.Vec2{1, 0}).Rotate(b.Angle_).Scale(frac)
targetDir := (linear.Vec2{1, 0}).Rotate(b.Target.Angle).Scale(1.0 - frac)
newDir := curDir.Add(targetDir)
if newDir.Mag() > 0.01 {
b.Angle_ = newDir.Angle()
}
}
}
