| // Copyright 2015 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "OrientationIterator.h" |
| |
| #include "wtf/PtrUtil.h" |
| |
| namespace blink { |
| |
| OrientationIterator::OrientationIterator(const UChar* buffer, |
| unsigned bufferSize, |
| FontOrientation runOrientation) |
| : m_utf16Iterator(makeUnique<UTF16TextIterator>(buffer, bufferSize)), |
| m_bufferSize(bufferSize), |
| m_atEnd(bufferSize == 0) { |
| // There's not much point in segmenting by isUprightInVertical if the text |
| // orientation is not "mixed". |
| ASSERT(runOrientation == FontOrientation::VerticalMixed); |
| } |
| |
| bool OrientationIterator::consume(unsigned* orientationLimit, |
| RenderOrientation* renderOrientation) { |
| if (m_atEnd) |
| return false; |
| |
| RenderOrientation currentRenderOrientation = OrientationInvalid; |
| UChar32 nextUChar32; |
| while (m_utf16Iterator->consume(nextUChar32)) { |
| if (currentRenderOrientation == OrientationInvalid || |
| !Character::isGraphemeExtended(nextUChar32)) { |
| RenderOrientation previousRenderOrientation = currentRenderOrientation; |
| currentRenderOrientation = |
| Character::isUprightInMixedVertical(nextUChar32) |
| ? OrientationKeep |
| : OrientationRotateSideways; |
| if (previousRenderOrientation != currentRenderOrientation && |
| previousRenderOrientation != OrientationInvalid) { |
| *orientationLimit = m_utf16Iterator->offset(); |
| *renderOrientation = previousRenderOrientation; |
| return true; |
| } |
| } |
| m_utf16Iterator->advance(); |
| } |
| *orientationLimit = m_bufferSize; |
| *renderOrientation = currentRenderOrientation; |
| m_atEnd = true; |
| return true; |
| } |
| |
| } // namespace blink |
