// Check if the given ship is within this projectile's blast radius. (The
// projectile will not explode unless it is also within the trigger radius.)
bool Projectile::InBlastRadius(const Ship &ship, int step, double closestHit) const
{
// "Invisible" ships can be killed by weapons with blast radii.
Point offset = position + closestHit * velocity - ship.Position();
if(offset.Length() <= weapon->BlastRadius())
return true;
const Mask &mask = ship.GetMask(step);
return mask.WithinRange(offset, ship.Facing(), weapon->BlastRadius());
}
// Check if this projectile collides with the given step, with the animation
// frame for the given step.
double Projectile::CheckCollision(const Ship &ship, int step) const
{
const Mask &mask = ship.GetMask(step);
Point offset = position - ship.Position();
double radius = weapon->TriggerRadius();
if(radius > 0. && mask.WithinRange(offset, angle, radius))
return 0.;
return mask.Collide(offset, velocity, ship.Facing());
}
