//-----------------------------------------------------------------------------
// Purpose: Calculates the physics shake values
//-----------------------------------------------------------------------------
void CASWEnvShake::Think( void )
{
int i;
if ( gpGlobals->curtime > m_nextShake )
{
// Higher frequency means we recalc the extents more often and perturb the display again
m_nextShake = gpGlobals->curtime + (1.0f / Frequency());
// Compute random shake extents (the shake will settle down from this)
for (i = 0; i < 2; i++ )
{
m_maxForce[i] = random->RandomFloat( -1, 1 );
}
// make the force it point mostly up
m_maxForce.z = 4;
VectorNormalize( m_maxForce );
m_maxForce *= m_currentAmp * 400; // amplitude is the acceleration of a 100kg object
}
float fraction = ( m_stopTime - gpGlobals->curtime ) / Duration();
if ( fraction < 0 )
{
m_pShakeController->ClearObjects();
return;
}
float freq = 0;
// Ramp up frequency over duration
if ( fraction )
{
freq = (Frequency() / fraction);
}
// square fraction to approach zero more quickly
fraction *= fraction;
// Sine wave that slowly settles to zero
fraction = fraction * sin( gpGlobals->curtime * freq );
// Add to view origin
for ( i = 0; i < 3; i++ )
{
// store the force in the controller callback
m_shakeCallback.m_force[i] = m_maxForce[i] * fraction;
}
// Drop amplitude a bit, less for higher frequency shakes
m_currentAmp -= m_currentAmp * ( gpGlobals->frametime / (Duration() * Frequency()) );
SetNextThink( gpGlobals->curtime );
}
//-----------------------------------------------------------------------------
// Purpose:
//-----------------------------------------------------------------------------
void CASWEnvShake::ApplyShake( ShakeCommand_t command )
{
if ( !HasSpawnFlags( SF_ASW_SHAKE_NO_VIEW ) )
{
bool air = (GetSpawnFlags() & SF_ASW_SHAKE_INAIR) ? true : false;
UTIL_ASW_ScreenShake( GetAbsOrigin(), Amplitude(), Frequency(), Duration(), Radius(), command, air );
}
if ( GetSpawnFlags() & SF_ASW_SHAKE_ROPES )
{
CRopeKeyframe::ShakeRopes( GetAbsOrigin(), Radius(), Frequency() );
}
if ( GetSpawnFlags() & SF_ASW_SHAKE_PHYSICS )
{
if ( !m_pShakeController )
{
m_pShakeController = physenv->CreateMotionController( &m_shakeCallback );
}
// do physics shake
switch( command )
{
case SHAKE_START:
{
m_stopTime = gpGlobals->curtime + Duration();
m_nextShake = 0;
m_pShakeController->ClearObjects();
SetNextThink( gpGlobals->curtime );
m_currentAmp = Amplitude();
CBaseEntity *list[1024];
float radius = Radius();
// probably checked "Shake Everywhere" do a big radius
if ( !radius )
{
radius = MAX_COORD_INTEGER;
}
Vector extents = Vector(radius, radius, radius);
Vector mins = GetAbsOrigin() - extents;
Vector maxs = GetAbsOrigin() + extents;
int count = UTIL_EntitiesInBox( list, 1024, mins, maxs, 0 );
for ( int i = 0; i < count; i++ )
{
//
// Only shake physics entities that players can see. This is one frame out of date
// so it's possible that we could miss objects if a player changed PVS this frame.
//
if ( ( list[i]->GetMoveType() == MOVETYPE_VPHYSICS ) )
{
IPhysicsObject *pPhys = list[i]->VPhysicsGetObject();
if ( pPhys && pPhys->IsMoveable() )
{
m_pShakeController->AttachObject( pPhys, false );
pPhys->Wake();
}
}
}
}
break;
case SHAKE_STOP:
m_pShakeController->ClearObjects();
break;
case SHAKE_AMPLITUDE:
m_currentAmp = Amplitude();
case SHAKE_FREQUENCY:
m_pShakeController->WakeObjects();
break;
}
}
}