Index: third_party/WebKit/Source/core/layout/ng/NGConstraintSpace.h |
diff --git a/third_party/WebKit/Source/core/layout/ng/NGConstraintSpace.h b/third_party/WebKit/Source/core/layout/ng/NGConstraintSpace.h |
new file mode 100644 |
index 0000000000000000000000000000000000000000..88a401e774f157ffb15262cfd5608216d2fa87b8 |
--- /dev/null |
+++ b/third_party/WebKit/Source/core/layout/ng/NGConstraintSpace.h |
@@ -0,0 +1,150 @@ |
+// Copyright 2016 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. |
+ |
+#ifndef NGConstraintSpace_h |
+#define NGConstraintSpace_h |
+ |
+#include "core/CoreExport.h" |
+#include "platform/LayoutUnit.h" |
+#include "wtf/DoublyLinkedList.h" |
+ |
+namespace blink { |
+ |
+class NGDerivedConstraintSpace; |
+class NGExclusion; |
+class NGFragment; |
+class NGLayoutOpportunityIterator; |
+ |
+enum NGExclusionType { |
+ ClearNone = 0, |
+ ClearFloatLeft = 1, |
+ ClearFloatRight = 2, |
+ ClearFragment = 4 |
+}; |
+ |
+enum NGFragmentationType { |
+ FragmentNone, |
+ FragmentPage, |
+ FragmentColumn, |
+ FragmentRegion |
+}; |
+ |
+enum NGExclusionFlowType { |
+ ExcludeNone, |
+ ExcludeInlineFlow, |
+ ExcludeInlineStart, |
+ ExcludeInlineEnd, |
+ ExcludeInlineBoth |
+}; |
+ |
+class NGExclusion { |
+public: |
+ NGExclusion(); |
+ ~NGExclusion() { } |
+}; |
+ |
+class CORE_EXPORT NGConstraintSpace { |
+public: |
+ NGConstraintSpace(LayoutUnit inlineSize, LayoutUnit blockSize); |
+ ~NGConstraintSpace() { } |
+ |
+ void addExclusion(const NGExclusion, unsigned options = 0); |
+ void setOverflowSize(LayoutUnit inlineSize, LayoutUnit blockSize); |
+ void setFixedSize(bool inlineFixed, bool blockFixed); |
+ void setFragmentationType(NGFragmentationType blockFragmentationType); |
+ |
+ // Available space in each direction, -1 indicates infinite space. |
+ LayoutUnit inlineSize() const { return m_inlineSize; } |
+ LayoutUnit blockSize() const { return m_blockSize; } |
+ |
+ // The size threashold in the inline and block directions respectively that |
+ // triggers the presence of a scrollbar. If exceeded the current layout |
+ // should be aborted and invoked again with a constraint space modified to |
+ // reserve space for a scrollbar. -1 indicates no limit. |
+ LayoutUnit inlineOverflowSize() const { return m_inlineOverflowSize; } |
+ LayoutUnit blockOverflowSize() const { return m_blockOverflowSize; } |
+ |
+ // Some layout modes “stretch” their children to a fixed size (e.g. flex, |
+ // grid). These flags represented whether a layout needs to produce a |
+ // fragment that satisfies a fixed constraint in the inline and block |
+ // direction respectively. |
+ bool fixedInlineSize() const { return m_fixedInlineSize; } |
+ bool fixedBlockSize() const { return m_fixedBlockSize; } |
+ |
+ // If specified a layout should produce a Fragment which fragments at the |
+ // blockSize if possible. |
+ NGFragmentationType blockFragmentationType() const |
+ { |
+ return static_cast<NGFragmentationType>(m_blockFragmentationType); |
+ } |
+ |
+ DoublyLinkedList<const NGExclusion> exclusions(unsigned options = 0) const; |
+ |
+ NGLayoutOpportunityIterator layoutOpportunities( |
+ unsigned clear = ClearNone, |
+ NGExclusionFlowType avoid = ExcludeNone) const; |
+ |
+ // Modifies constraint space to account for a placed fragment. Depending on |
+ // the shape of the fragment this will either modify the inline or block |
+ // size, or add an exclusion. |
+ void subtract(const NGFragment); |
+ |
+private: |
+ LayoutUnit m_inlineSize; |
+ LayoutUnit m_blockSize; |
+ LayoutUnit m_inlineOverflowSize; |
+ LayoutUnit m_blockOverflowSize; |
+ |
+ unsigned m_fixedInlineSize : 1; |
+ unsigned m_fixedBlockSize : 1; |
+ unsigned m_blockFragmentationType : 2; |
+ |
+ DoublyLinkedList<const NGExclusion> m_exclusions; |
+}; |
+ |
+ |
+class CORE_EXPORT NGLayoutOpportunityIterator final { |
+public: |
+ NGLayoutOpportunityIterator(const NGConstraintSpace* space, |
+ unsigned clear, NGExclusionFlowType avoid) |
+ : m_constraintSpace(space) |
+ , m_clear(clear) |
+ , m_avoid(avoid) { } |
+ ~NGLayoutOpportunityIterator() { } |
+ |
+ const NGDerivedConstraintSpace* next(); |
+ |
+private: |
+ const NGConstraintSpace* m_constraintSpace; |
+ unsigned m_clear; |
+ NGExclusionFlowType m_avoid; |
+}; |
+ |
+ |
+class CORE_EXPORT NGDerivedConstraintSpace final : NGConstraintSpace { |
+public: |
+ ~NGDerivedConstraintSpace(); |
+ |
+ LayoutUnit inlineOffset() const; |
+ LayoutUnit blockOffset() const; |
+ |
+ // When creating a derived NGConstraintSpace for the next inline level |
+ // layout opportunity, inlineSize and blockSize of the NGConstraintSpace |
+ // may be different from its parent. These properties hold the inline and |
+ // block size of the original NGConstraintSpaces, allowing percentage |
+ // resolution to work correctly. |
+ LayoutUnit inlineSizeForPercentageResolution() const; |
+ LayoutUnit blockSizeForPercentageResolution() const; |
+ |
+private: |
+ NGDerivedConstraintSpace(); |
+ |
+ LayoutUnit m_inlineOffset; |
+ LayoutUnit m_blockOffset; |
+ NGConstraintSpace* m_original; |
+}; |
+ |
+} // namespace blink |
+ |
+#endif // NGConstraintSpace_h |