1 #include "config.h" 2 #include "ScrollableLayerAndroid.h" 3 4 #if USE(ACCELERATED_COMPOSITING) 5 6 namespace WebCore { 7 8 bool ScrollableLayerAndroid::scrollTo(int x, int y) 9 { 10 SkIRect scrollBounds; 11 getScrollRect(&scrollBounds); 12 if (!scrollBounds.fRight && !scrollBounds.fBottom) 13 return false; 14 15 SkScalar newX = SkScalarPin(x, 0, scrollBounds.fRight); 16 SkScalar newY = SkScalarPin(y, 0, scrollBounds.fBottom); 17 // Check for no change. 18 if (newX == scrollBounds.fLeft && newY == scrollBounds.fTop) 19 return false; 20 21 setPosition(m_scrollLimits.fLeft - newX, m_scrollLimits.fTop - newY); 22 return true; 23 } 24 25 void ScrollableLayerAndroid::getScrollRect(SkIRect* out) const 26 { 27 const SkPoint& pos = getPosition(); 28 out->fLeft = m_scrollLimits.fLeft - pos.fX; 29 out->fTop = m_scrollLimits.fTop - pos.fY; 30 out->fRight = getSize().width() - m_scrollLimits.width(); 31 out->fBottom = getSize().height() - m_scrollLimits.height(); 32 } 33 34 bool ScrollableLayerAndroid::scrollRectIntoView(const SkIRect& rect) 35 { 36 // Apply the local transform to the rect to get it relative to the parent 37 // layer. 38 SkMatrix localTransform; 39 getLocalTransform(&localTransform); 40 SkRect transformedRect; 41 transformedRect.set(rect); 42 localTransform.mapRect(&transformedRect); 43 44 // Test left before right to prioritize left alignment if transformedRect is wider than 45 // visible area. 46 int x = m_scrollLimits.fLeft; 47 if (transformedRect.fLeft < m_scrollLimits.fLeft) 48 x = transformedRect.fLeft; 49 else if (transformedRect.fRight > m_scrollLimits.fRight) 50 x = transformedRect.fRight - std::max(m_scrollLimits.width(), transformedRect.width()); 51 52 // Test top before bottom to prioritize top alignment if transformedRect is taller than 53 // visible area. 54 int y = m_scrollLimits.fTop; 55 if (transformedRect.fTop < m_scrollLimits.fTop) 56 y = transformedRect.fTop; 57 else if (transformedRect.fBottom > m_scrollLimits.fBottom) 58 y = transformedRect.fBottom - std::max(m_scrollLimits.height(), transformedRect.height()); 59 60 return scrollTo(x - getPosition().fX, y - getPosition().fY); 61 } 62 63 } // namespace WebCore 64 65 #endif // USE(ACCELERATED_COMPOSITING) 66
