-/**
- * Returns whether to lock scrolling to a particular axis
- *
- * @param[in] panDelta Distance panned since gesture started
- * @param[in] currentLockAxis The current lock axis value
- * @param[in] lockGradient How quickly to lock to a particular axis
- *
- * @return The new axis lock state
- */
-ScrollView::LockAxis GetLockAxis(const Vector2& panDelta, ScrollView::LockAxis currentLockAxis, float lockGradient)
-{
- if(panDelta.LengthSquared() > AUTOLOCK_AXIS_MINIMUM_DISTANCE2 &&
- currentLockAxis == ScrollView::LockPossible)
- {
- float dx = fabsf(panDelta.x);
- float dy = fabsf(panDelta.y);
- if(dx * lockGradient >= dy)
- {
- // 0.36:1 gradient to the horizontal (deviate < 20 degrees)
- currentLockAxis = ScrollView::LockVertical;
- }
- else if(dy * lockGradient > dx)
- {
- // 0.36:1 gradient to the vertical (deviate < 20 degrees)
- currentLockAxis = ScrollView::LockHorizontal;
- }
- else
- {
- currentLockAxis = ScrollView::LockNone;
- }
- }
- return currentLockAxis;
-}
-
-/**
- * Internal Pre-Position Property Constraint.
- *
- * Generates position property based on current position + gesture displacement.
- * Or generates position property based on positionX/Y.
- * Note: This is the position prior to any clamping at scroll boundaries.
- */
-struct InternalPrePositionConstraint
-{
- InternalPrePositionConstraint(const Vector2& initialPanPosition,
- const Vector2& initialPanMask,
- bool axisAutoLock,
- float axisAutoLockGradient,
- ScrollView::LockAxis initialLockAxis,
- const Vector2& maxOvershoot,
- const RulerPtr& rulerX,
- const RulerPtr& rulerY)
- : mLocalStart(initialPanPosition),
- mInitialPanMask(initialPanMask),
- mMaxOvershoot(maxOvershoot),
- mAxisAutoLockGradient(axisAutoLockGradient),
- mLockAxis(initialLockAxis),
- mAxisAutoLock(axisAutoLock),
- mWasPanning(false)
- {
- const RulerDomain& rulerDomainX = rulerX->GetDomain();
- const RulerDomain& rulerDomainY = rulerY->GetDomain();
- mDomainMin = Vector2(rulerDomainX.min, -rulerDomainY.min);
- mDomainMax = Vector2(-rulerDomainX.max, -rulerDomainY.max);
- mClampX = rulerDomainX.enabled;
- mClampY = rulerDomainY.enabled;
- mFixedRulerX = rulerX->GetType() == Ruler::FIXED;
- mFixedRulerY = rulerY->GetType() == Ruler::FIXED;
- }
-
- void operator()(Vector2& scrollPostPosition, const PropertyInputContainer& inputs)
- {
- const Vector2& panPosition = inputs[0]->GetVector2();
- const bool& inGesture = inputs[1]->GetBoolean();
-
- // First check if we are within a gesture.
- // The ScrollView may have received a start gesture from ::OnPan()
- // while the finish gesture is received now in this constraint.
- // This gesture must then be rejected as the value will be "old".
- // Typically the last value from the end of the last gesture.
- // If we are rejecting the gesture, we simply don't modify the constraint target.
- if(inGesture)
- {
- if(!mWasPanning)
- {
- mPrePosition = scrollPostPosition;
- mStartPosition = mPrePosition;
- mCurrentPanMask = mInitialPanMask;
- mWasPanning = true;
- }
-
- // Calculate Deltas...
- const Vector2& currentPosition = panPosition;
- Vector2 panDelta(currentPosition - mLocalStart);
-
- // Axis Auto Lock - locks the panning to the horizontal or vertical axis if the pan
- // appears mostly horizontal or mostly vertical respectively...
- if(mAxisAutoLock)
- {
- mLockAxis = GetLockAxis(panDelta, mLockAxis, mAxisAutoLockGradient);
- if(mLockAxis == ScrollView::LockVertical)
- {
- mCurrentPanMask.y = 0.0f;
- }
- else if(mLockAxis == ScrollView::LockHorizontal)
- {
- mCurrentPanMask.x = 0.0f;
- }
- }
-
- // Restrict deltas based on ruler enable/disable and axis-lock state...
- panDelta *= mCurrentPanMask;
-
- // Perform Position transform based on input deltas...
- scrollPostPosition = mPrePosition;
- scrollPostPosition += panDelta;
-
- // if no wrapping then clamp preposition to maximum overshoot amount
- const Vector3& size = inputs[2]->GetVector3();
- if(mClampX)
- {
- float newXPosition = Clamp(scrollPostPosition.x, (mDomainMax.x + size.x) - mMaxOvershoot.x, mDomainMin.x + mMaxOvershoot.x);
- if((newXPosition < scrollPostPosition.x - Math::MACHINE_EPSILON_1) || (newXPosition > scrollPostPosition.x + Math::MACHINE_EPSILON_1))
- {
- mPrePosition.x = newXPosition;
- mLocalStart.x = panPosition.x;
- }
- scrollPostPosition.x = newXPosition;
- }
- if(mClampY)
- {
- float newYPosition = Clamp(scrollPostPosition.y, (mDomainMax.y + size.y) - mMaxOvershoot.y, mDomainMin.y + mMaxOvershoot.y);
- if((newYPosition < scrollPostPosition.y - Math::MACHINE_EPSILON_1) || (newYPosition > scrollPostPosition.y + Math::MACHINE_EPSILON_1))
- {
- mPrePosition.y = newYPosition;
- mLocalStart.y = panPosition.y;
- }
- scrollPostPosition.y = newYPosition;
- }
-
- // If we are using a fixed ruler in a particular axis, limit the maximum pages scrolled on that axis.
- if(mFixedRulerX || mFixedRulerY)
- {
- // Here we limit the maximum amount that can be moved from the starting position of the gesture to one page.
- // We do this only if we have a fixed ruler (on that axis) and the mode is enabled.
- // Note: 1.0f is subtracted to keep the value within one page size (otherwise we stray on to the page after).
- // Note: A further 1.0f is subtracted to handle a compensation that happens later within the flick handling code in SnapWithVelocity().
- // When a flick is completed, an adjustment of 1.0f is sometimes made to allow for the scenario where:
- // A flick finishes before the update thread has advanced the scroll position past the previous snap point.
- Vector2 viewPageSizeLimit(size.x - (1.0f + 1.0f), size.y - (1.0f - 1.0f));
- Vector2 minPosition(mStartPosition.x - viewPageSizeLimit.x, mStartPosition.y - viewPageSizeLimit.y);
- Vector2 maxPosition(mStartPosition.x + viewPageSizeLimit.x, mStartPosition.y + viewPageSizeLimit.y);
-
- if(mFixedRulerX)
- {
- scrollPostPosition.x = Clamp(scrollPostPosition.x, minPosition.x, maxPosition.x);
- }
- if(mFixedRulerY)
- {
- scrollPostPosition.y = Clamp(scrollPostPosition.y, minPosition.y, maxPosition.y);
- }
- }
- }
- }
-
- Vector2 mPrePosition;
- Vector2 mLocalStart;
- Vector2 mStartPosition; ///< The start position of the gesture - used to limit scroll amount (not modified by clamping).
- Vector2 mInitialPanMask; ///< Initial pan mask (based on ruler settings).
- Vector2 mCurrentPanMask; ///< Current pan mask that can be altered by axis lock mode.
- Vector2 mDomainMin;
- Vector2 mDomainMax;
- Vector2 mMaxOvershoot;
-
- float mAxisAutoLockGradient; ///< Set by ScrollView
- ScrollView::LockAxis mLockAxis;
-
- bool mAxisAutoLock : 1; ///< Set by ScrollView
- bool mWasPanning : 1;
- bool mClampX : 1;
- bool mClampY : 1;
- bool mFixedRulerX : 1;
- bool mFixedRulerY : 1;
-};
-
-/**
- * Internal Position Property Constraint.
- *
- * Generates position property based on pre-position
- * Note: This is the position after clamping.
- * (uses result of InternalPrePositionConstraint)
- */
-struct InternalPositionConstraint
-{
- InternalPositionConstraint(const RulerDomain& domainX, const RulerDomain& domainY, bool wrap)
- : mDomainMin(-domainX.min, -domainY.min),
- mDomainMax(-domainX.max, -domainY.max),
- mClampX(domainX.enabled),
- mClampY(domainY.enabled),
- mWrap(wrap)
- {
- }
-
- void operator()(Vector2& position, const PropertyInputContainer& inputs)
- {
- position = inputs[0]->GetVector2();
- const Vector2& size = inputs[3]->GetVector3().GetVectorXY();
- const Vector2& min = inputs[1]->GetVector2();
- const Vector2& max = inputs[2]->GetVector2();
-
- if(mWrap)
- {
- position.x = -WrapInDomain(-position.x, min.x, max.x);
- position.y = -WrapInDomain(-position.y, min.y, max.y);
- }
- else
- {
- // clamp post position to domain
- position.x = mClampX ? Clamp(position.x, mDomainMax.x + size.x, mDomainMin.x) : position.x;
- position.y = mClampY ? Clamp(position.y, mDomainMax.y + size.y, mDomainMin.y) : position.y;
- }
- }
-
- Vector2 mDomainMin;
- Vector2 mDomainMax;
- bool mClampX;
- bool mClampY;
- bool mWrap;
-};
-
-/**
- * This constraint updates the X overshoot property using the difference
- * SCROLL_PRE_POSITION.x and SCROLL_POSITION.x, returning a relative value between 0.0f and 1.0f
- */
-struct OvershootXConstraint
-{
- OvershootXConstraint(float maxOvershoot)
- : mMaxOvershoot(maxOvershoot)
- {
- }
-
- void operator()(float& current, const PropertyInputContainer& inputs)
- {
- if(inputs[2]->GetBoolean())
- {
- const Vector2& scrollPrePosition = inputs[0]->GetVector2();
- const Vector2& scrollPostPosition = inputs[1]->GetVector2();
- float newOvershoot = scrollPrePosition.x - scrollPostPosition.x;
- current = (newOvershoot > 0.0f ? std::min(newOvershoot, mMaxOvershoot) : std::max(newOvershoot, -mMaxOvershoot)) / mMaxOvershoot;
- }
- else
- {
- current = 0.0f;
- }
- }
-
- float mMaxOvershoot;
-};
-
-/**
- * This constraint updates the Y overshoot property using the difference
- * SCROLL_PRE_POSITION.y and SCROLL_POSITION.y, returning a relative value between 0.0f and 1.0f
- */
-struct OvershootYConstraint
-{
- OvershootYConstraint(float maxOvershoot)
- : mMaxOvershoot(maxOvershoot)
- {
- }
-
- void operator()(float& current, const PropertyInputContainer& inputs)
- {
- if(inputs[2]->GetBoolean())
- {
- const Vector2& scrollPrePosition = inputs[0]->GetVector2();
- const Vector2& scrollPostPosition = inputs[1]->GetVector2();
- float newOvershoot = scrollPrePosition.y - scrollPostPosition.y;
- current = (newOvershoot > 0.0f ? std::min(newOvershoot, mMaxOvershoot) : std::max(newOvershoot, -mMaxOvershoot)) / mMaxOvershoot;
- }
- else
- {
- current = 0.0f;
- }
- }
-
- float mMaxOvershoot;
-};
-
-/**
- * Internal Position-Delta Property Constraint.
- *
- * Generates position-delta property based on scroll-position + scroll-offset properties.
- */
-void InternalPositionDeltaConstraint(Vector2& current, const PropertyInputContainer& inputs)
-{
- const Vector2& scrollPosition = inputs[0]->GetVector2();
- const Vector2& scrollOffset = inputs[1]->GetVector2();
-
- current = scrollPosition + scrollOffset;
-}
-
-/**
- * Internal Final Position Constraint
- * The position of content is:
- * of scroll-position + f(scroll-overshoot)
- * where f(...) function defines how overshoot
- * should affect final-position.
- */
-struct InternalFinalConstraint
-{
- InternalFinalConstraint(AlphaFunctionPrototype functionX,
- AlphaFunctionPrototype functionY)
- : mFunctionX(functionX),
- mFunctionY(functionY)
- {
- }
-
- void operator()(Vector2& current, const PropertyInputContainer& inputs)
- {
- const float& overshootx = inputs[1]->GetFloat();
- const float& overshooty = inputs[2]->GetFloat();
- Vector2 offset(mFunctionX(overshootx),
- mFunctionY(overshooty));
-
- current = inputs[0]->GetVector2() - offset;
- }
-
- AlphaFunctionPrototype mFunctionX;
- AlphaFunctionPrototype mFunctionY;
-};
-
projects / platform / core / uifw / dali-toolkit.git / blobdiff