void TBScroller::OnScrollBy(int dx, int dy, bool accumulative)
{
if (!IsStarted())
Start();
float ppms_x = m_func.GetSpeedFromDistance((float)dx);
float ppms_y = m_func.GetSpeedFromDistance((float)dy);
if (accumulative && IsScrolling())
{
TBWidget::ScrollInfo info = m_target->GetScrollInfo();
// If new direction is the same as the current direction,
// calculate the speed needed for the remaining part and
// add that to the new scroll speed.
if (ppms_x < 0 == m_scroll_start_speed_ppms_x < 0)
{
int distance_x = m_func.GetDistanceAtTimeInt(m_scroll_start_speed_ppms_x,
m_func.GetDurationFromSpeed(m_scroll_start_speed_ppms_x));
int distance_remaining_x = m_scroll_start_scroll_x + distance_x - info.x;
distance_remaining_x += m_func.GetDistanceAtTimeInt(ppms_x, m_func.GetDurationFromSpeed(ppms_x));
ppms_x = m_func.GetSpeedFromDistance((float)distance_remaining_x);
}
if (ppms_y < 0 == m_scroll_start_speed_ppms_y < 0)
{
int distance_y = m_func.GetDistanceAtTimeInt(m_scroll_start_speed_ppms_y,
m_func.GetDurationFromSpeed(m_scroll_start_speed_ppms_y));
int distance_remaining_y = m_scroll_start_scroll_y + distance_y - info.y;
distance_remaining_y += m_func.GetDistanceAtTimeInt(ppms_y, m_func.GetDurationFromSpeed(ppms_y));
ppms_y = m_func.GetSpeedFromDistance((float)distance_remaining_y);
}
}
AdjustToSnappingAndScroll(ppms_x, ppms_y);
}
void OvrScrollManager::Frame( float deltaSeconds, unsigned int controllerState )
{
// --
// Controller Input Handling
bool forwardScrolling = false;
bool backwardScrolling = false;
if( CurrentScrollType == HORIZONTAL_SCROLL )
{
forwardScrolling = ( controllerState & ( BUTTON_LSTICK_RIGHT | BUTTON_DPAD_RIGHT ) ) != 0;
backwardScrolling = ( controllerState & ( BUTTON_LSTICK_LEFT | BUTTON_DPAD_LEFT ) ) != 0;
}
else if( CurrentScrollType == VERTICAL_SCROLL )
{
forwardScrolling = ( controllerState & ( BUTTON_LSTICK_DOWN | BUTTON_DPAD_DOWN ) ) != 0;
backwardScrolling = ( controllerState & ( BUTTON_LSTICK_UP | BUTTON_DPAD_UP ) ) != 0;
}
if ( forwardScrolling || backwardScrolling )
{
CurrentScrollState = SMOOTH_SCROLL;
}
SetEnableAutoForwardScrolling( forwardScrolling );
SetEnableAutoBackwardScrolling( backwardScrolling );
// --
// Logic update for the current scroll state
switch( CurrentScrollState )
{
case SMOOTH_SCROLL:
{
// Auto scroll during wrap around initiation.
if( ( !RestrictedScrolling ) || // Either not restricted scrolling
( RestrictedScrolling && ( TouchDirectionLocked != NO_LOCK ) ) ) // or restricted scrolling with touch direction locked
{
if ( TouchIsDown )
{
if ( ( Position < 0.0f ) || ( Position > MaxPosition ) )
{
// When scrolled out of bounds and touch is still down,
// auto-scroll to initiate wrap around easily.
float totalDistance = 0.0f;
for ( int i = 0; i < Deltas.GetNum(); ++i )
{
totalDistance += Deltas[i].d;
}
if ( totalDistance < -EPSILON_VEL )
{
Velocity = -1.0f;
}
else if ( totalDistance > EPSILON_VEL )
{
Velocity = 1.0f;
}
else
{
Velocity = PrevAutoScrollVelocity;
}
}
else
{
Velocity = 0.0f;
}
PrevAutoScrollVelocity = Velocity;
}
}
if ( !IsScrolling() && IsOutOfBounds() )
{
CurrentScrollState = BOUNCE_SCROLL;
const float bounceBackVelocity = ScrollBehavior.BounceBackVelocity;
if ( Position < 0.0f )
{
Velocity = bounceBackVelocity;
}
else if ( Position > MaxPosition )
{
Velocity = -bounceBackVelocity;
}
Velocity = GetModifiedVelocity( Velocity );
}
}
break;
case BOUNCE_SCROLL:
{
if( !IsOutOfBounds() )
{
CurrentScrollState = SMOOTH_SCROLL;
if( Velocity > 0.0f ) // Pulled at the beginning
{
Position = 0.0f;
}
else if( Velocity < 0.0f ) // Pulled at the end
{
Position = MaxPosition;
}
Velocity = 0.0f;
}
}
break;
}
// --
// Scrolling physics update
AccumulatedDeltaTimeInSeconds += deltaSeconds;
OVR_ASSERT( AccumulatedDeltaTimeInSeconds <= 10.0f );
while( true )
{
if( AccumulatedDeltaTimeInSeconds < 0.016f )
{
break;
}
AccumulatedDeltaTimeInSeconds -= 0.016f;
if( CurrentScrollState == SMOOTH_SCROLL || CurrentScrollState == BOUNCE_SCROLL ) // While wrap around don't slow down scrolling
{
Velocity -= Velocity * ScrollBehavior.FrictionPerSec * 0.016f;
if( fabsf(Velocity) < EPSILON_VEL )
{
Velocity = 0.0f;
}
}
Position += Velocity * 0.016f;
if( CurrentScrollState == BOUNCE_SCROLL )
{
if( Velocity > 0.0f )
{
Position = Alg::Clamp( Position, -ScrollBehavior.Padding, MaxPosition );
}
else
{
Position = Alg::Clamp( Position, 0.0f, MaxPosition + ScrollBehavior.Padding );
}
}
else
{
Position = Alg::Clamp( Position, -ScrollBehavior.Padding, MaxPosition + ScrollBehavior.Padding );
}
}
}
void TBScroller::StopOrSnapScroll()
{
AdjustToSnappingAndScroll(0, 0);
if (!IsScrolling())
Stop();
}
