void
ctCameraScript_LooseLead::Update( float timeStep )
{
float delta = m_targetPosition.x - m_position.x;
if ( vsFabs(delta) > 4.f )
{
m_following = true;
}
if ( m_following )
{
vsVector2D predictedPosition = m_targetPosition;
predictedPosition.x += ctPlayer::Instance()->GetVelocity().x * 2.f;
m_spring.SetCenter( predictedPosition );
if ( vsFabs(ctPlayer::Instance()->GetVelocity().x) <= 0.f )
{
m_following = false;
}
}
else
{
m_spring.SetCenter( m_position );
}
m_position = m_spring.Update( timeStep );
}
float
vsVector2D::ApproximateLength() const
{
const float factor = (1.0f + 1.0f/(4.0f-2.0f*SQRT_TWO))/2.0f;
float ax = vsFabs(x);
float ay = vsFabs(y);
return factor * vsMin((1.0f / SQRT_TWO)*(ax+ay), vsMax(ax, ay));
}
void
astPlayerShip::HandleSpawnTimer( float timeStep )
{
m_timeSinceSpawn += timeStep;
const float c_invulnerableTime = 3.0f; // three seconds of invulnerability
if ( m_spawnInvulnerable )
{
float scale = 1.0f;
vsColor c = vsColor::Blue;
if ( m_timeSinceSpawn > c_invulnerableTime )
{
SetCollisionsActive(true);
m_spawnInvulnerable = false;
}
else if ( m_timeSinceSpawn > 2.0f )
{
float frac = (m_timeSinceSpawn - 2.0f);
float theta = frac * TWOPI;
float pulseAmt = vsFabs(vsSin(theta));
c = vsInterpolate(pulseAmt, vsColor::LightBlue, vsColor::White);
}
else if ( m_timeSinceSpawn > 1.0f )
{
float frac = (m_timeSinceSpawn - 1.0f);
float theta = frac * TWOPI;
float pulseAmt = vsFabs(vsSin(theta));
c = vsInterpolate(pulseAmt, vsColor::LightBlue, vsColor::White);
}
else
{
c = vsInterpolate(m_timeSinceSpawn, vsColor::Black, vsColor::LightBlue);
}
const float c_scaleTime = 3.0f;
if ( m_timeSinceSpawn < c_scaleTime )
{
float frac = m_timeSinceSpawn / c_scaleTime;
frac = 1.0f - ((frac-1.f) * (frac-1.f)); // slam in, ease out
//frac = (3.0f * frac * frac) - (2.0f * frac * frac * frac); // ease in, ease out
scale = vsInterpolate( frac, 5.0f, 1.0f );
}
SetColor(c);
m_transform.SetScale( vsVector2D(scale,scale) );
}
}
float
vsSpline3D::ClosestTimeTo( const vsVector3D& position )
{
//lastBestT is a composite value;
//the whole part is the "before" knot, and the fraction
//is the 't' for that segment.
float lastBestT = 0.5f;
float lastMove = 1.f;
float scale = 0.75f;
vsVector3D lastBestPoint;
vsVector3D lastBestTangent;
int iterations = 0;
while ( lastMove > 0.0001f )
{
lastBestPoint = PositionAtTime(lastBestT);
lastBestTangent = VelocityAtTime(lastBestT);
vsVector3D delta = position - lastBestPoint;
float move = lastBestTangent.Dot(delta) / lastBestTangent.SqLength();
move = vsClamp(move, -lastMove*scale, lastMove*scale);
lastBestT = vsClamp( lastBestT+move, 0.f, 1.f );
lastMove = vsFabs(move);
iterations++;
}
return lastBestT;
}
