caching some values for faster valueAt calculations

This commit is contained in:
Uwe Rathmann 2023-02-04 11:53:54 +01:00
parent 9d4c423591
commit ca70fec579
2 changed files with 49 additions and 8 deletions

View File

@ -40,6 +40,7 @@ void QskLinearDirection::setVector( const QLineF& vector ) noexcept
m_y1 = vector.y1();
m_x2 = vector.x2();
m_y2 = vector.y2();
m_dot = -1.0;
}
void QskLinearDirection::setVector( const QPointF& start, const QPointF& stop ) noexcept
@ -48,6 +49,7 @@ void QskLinearDirection::setVector( const QPointF& start, const QPointF& stop )
m_y1 = start.y();
m_x2 = stop.x();
m_y2 = stop.y();
m_dot = -1.0;
}
void QskLinearDirection::setVector( qreal x1, qreal y1, qreal x2, qreal y2 ) noexcept
@ -56,50 +58,59 @@ void QskLinearDirection::setVector( qreal x1, qreal y1, qreal x2, qreal y2 ) noe
m_y1 = y1;
m_x2 = x2;
m_y2 = y2;
m_dot = -1.0;
}
void QskLinearDirection::setStart( const QPointF& pos ) noexcept
{
m_x1 = pos.x();
m_y1 = pos.y();
m_dot = -1.0;
}
void QskLinearDirection::setStart( qreal x, qreal y ) noexcept
{
m_x1 = x;
m_y1 = y;
m_dot = -1.0;
}
void QskLinearDirection::setStop( const QPointF& pos ) noexcept
{
m_x2 = pos.x();
m_y2 = pos.y();
m_dot = -1.0;
}
void QskLinearDirection::setStop( qreal x, qreal y ) noexcept
{
m_x2 = x;
m_y2 = y;
m_dot = -1.0;
}
void QskLinearDirection::setX1( qreal x ) noexcept
{
m_x1 = x;
m_dot = -1.0;
}
void QskLinearDirection::setY1( qreal y ) noexcept
{
m_y1 = y;
m_dot = -1.0;
}
void QskLinearDirection::setX2( qreal x ) noexcept
{
m_x2 = x;
m_dot = -1.0;
}
void QskLinearDirection::setY2( qreal y ) noexcept
{
m_y2 = y;
m_dot = -1.0;
}
void QskLinearDirection::setInterval( Qt::Orientation orientation, qreal from, qreal to )
@ -114,6 +125,14 @@ void QskLinearDirection::setInterval( Qt::Orientation orientation, qreal from, q
m_x1 = from;
m_x2 = to;
}
m_dot = -1.0;
}
void QskLinearDirection::precalculate() const noexcept
{
m_dx = m_x2 - m_x1;
m_dy = m_y2 - m_y1;
m_dot = m_dx * m_dx + m_dy * m_dy;
}
static inline bool qskIntersectsTop(
@ -133,14 +152,14 @@ static inline bool qskIntersectsBottom(
static inline bool qskIntersectsLeft(
qreal vx, qreal vy, qreal m, const QRectF& rect )
{
const qreal cy = vy - ( vx - rect.left() ) * m;
const auto cy = vy - ( vx - rect.left() ) * m;
return ( cy > rect.top() && cy < rect.bottom() );
}
static inline bool qskIntersectsRight(
qreal vx, qreal vy, qreal m, const QRectF& rect )
{
const qreal cy = vy - ( vx - rect.right() ) * m;
const auto cy = vy - ( vx - rect.right() ) * m;
return ( cy > rect.top() && cy < rect.bottom() );
}
@ -152,7 +171,6 @@ bool QskLinearDirection::contains( const QRectF& rect ) const
|| ( m_x1 >= rect.right() && m_x2 <= rect.left() );
}
if ( m_x1 == m_x2 )
{
return ( m_y1 <= rect.top() && m_y2 >= rect.bottom() )

View File

@ -68,6 +68,9 @@ class QSK_EXPORT QskLinearDirection
constexpr qreal y2() const noexcept;
void setY2( qreal ) noexcept;
qreal dx() const noexcept;
qreal dy() const noexcept;
/*
In direction of the gradient vector, where 0.0 corresponds to
points on the perpendicular at the start and 1.0 to points on
@ -82,10 +85,16 @@ class QSK_EXPORT QskLinearDirection
bool contains( const QRectF& ) const;
private:
void precalculate() const noexcept;
qreal m_x1 = 0.0;
qreal m_y1 = 0.0;
qreal m_x2 = 0.0;
qreal m_y2 = 1.0;
mutable qreal m_dx = 0.0;
mutable qreal m_dy = 0.0;
mutable qreal m_dot = -1.0;
};
class QSK_EXPORT QskConicDirection
@ -219,6 +228,22 @@ inline constexpr qreal QskLinearDirection::y2() const noexcept
return m_y2;
}
inline qreal QskLinearDirection::dx() const noexcept
{
if ( m_dot < 0.0 )
precalculate();
return m_dx;
}
inline qreal QskLinearDirection::dy() const noexcept
{
if ( m_dot < 0.0 )
precalculate();
return m_dy;
}
inline constexpr QLineF QskLinearDirection::vector() const noexcept
{
return QLineF( m_x1, m_y1, m_x2, m_y2 );
@ -262,12 +287,10 @@ inline qreal QskLinearDirection::valueAt( const QPointF& pos ) const
inline qreal QskLinearDirection::valueAt( qreal x, qreal y ) const
{
// we could cache these values TODO ..
const qreal dx = m_x2 - m_x1;
const qreal dy = m_y2 - m_y1;
const qreal dot = dx * dx + dy * dy;
if ( m_dot < 0.0 )
precalculate();
return ( ( x - m_x1 ) * dx + ( y - m_y1 ) * dy ) / dot;
return ( ( x - m_x1 ) * m_dx + ( y - m_y1 ) * m_dy ) / m_dot;
}
inline constexpr QskConicDirection::QskConicDirection(