Changeset 231953 in webkit

Timestamp:

May 18, 2018 7:31:02 AM (6 years ago)

Author:

Alan Bujtas

Message:

[LFC] Implement height computation for replaced elements.
​https://bugs.webkit.org/show_bug.cgi?id=185756

Reviewed by Antti Koivisto.

• layout/FormattingContext.cpp:

(WebCore::Layout::FormattingContext::computeHeight const):
(WebCore::Layout::FormattingContext::computeOutOfFlowWidth const):
(WebCore::Layout::FormattingContext::computeOutOfFlowHeight const):
(WebCore::Layout::FormattingContext::computeFloatingHeight const):
(WebCore::Layout::FormattingContext::computeReplacedHeight const):
(WebCore::Layout::FormattingContext::computeReplacedWidth const):
(WebCore::Layout::FormattingContext::computeOutOfFlowReplacedHeight const):

• layout/FormattingContext.h:

Location:

trunk/Source/WebCore

Files:

• ChangeLog (modified) (1 diff)
• layout/FormattingContext.cpp (modified) (6 diffs)
• layout/FormattingContext.h (modified) (3 diffs)
• layout/blockformatting/BlockFormattingContext.cpp (modified) (1 diff)

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2018-05-18  Zalan Bujtas  <zalan@apple.com>
+
+        [LFC] Implement height computation for replaced elements.
+        https://bugs.webkit.org/show_bug.cgi?id=185756
+
+        Reviewed by Antti Koivisto.
+
+        * layout/FormattingContext.cpp:
+        (WebCore::Layout::FormattingContext::computeHeight const):
+        (WebCore::Layout::FormattingContext::computeOutOfFlowWidth const):
+        (WebCore::Layout::FormattingContext::computeOutOfFlowHeight const):
+        (WebCore::Layout::FormattingContext::computeFloatingHeight const):
+        (WebCore::Layout::FormattingContext::computeReplacedHeight const):
+        (WebCore::Layout::FormattingContext::computeReplacedWidth const):
+        (WebCore::Layout::FormattingContext::computeOutOfFlowReplacedHeight const):
+        * layout/FormattingContext.h:
+
 2018-05-18  Zalan Bujtas  <zalan@apple.com>
 

trunk/Source/WebCore/layout/FormattingContext.cpp

@@ -75 +75 @@
         return computeOutOfFlowHeight(layoutContext, layoutBox, displayBox);
     if (layoutBox.isFloatingPositioned())
-        return computeFloatingHeight(layoutBox, displayBox);
+        return computeFloatingHeight(layoutContext, layoutBox, displayBox);
     return computeInFlowHeight(layoutContext, layoutBox, displayBox);
 }
@@ -85 +85 @@
         return;
     }
-    ASSERT_NOT_IMPLEMENTED_YET();
+    computeOutOfFlowReplacedWidth(layoutContext, layoutBox, displayBox);
 }
 
@@ -103 +103 @@
         return;
     }
-    ASSERT_NOT_IMPLEMENTED_YET();
-}
-
-void FormattingContext::computeFloatingHeight(const Box&, Display::Box&) const
-{
+    computeOutOfFlowReplacedHeight(layoutContext, layoutBox, displayBox);
+}
+
+void FormattingContext::computeFloatingHeight(LayoutContext& layoutContext, const Box& layoutBox, Display::Box& displayBox) const
+{
+    if (!layoutBox.replaced()) {
+        ASSERT_NOT_IMPLEMENTED_YET();
+        return;
+    }
+    computeReplacedHeight(layoutContext, layoutBox, displayBox);
 }
 
@@ -209 +214 @@
     else
         ASSERT_NOT_REACHED();
+
+    displayBox.setHeight(computedHeightValue);
+}
+
+void FormattingContext::computeReplacedHeight(LayoutContext&, const Box& layoutBox, Display::Box& displayBox) const
+{
+    ASSERT((layoutBox.isOutOfFlowPositioned() || layoutBox.isFloatingPositioned() || layoutBox.isInFlow()) && layoutBox.replaced());
+    // 10.6.5 Absolutely positioned, replaced elements. The used value of 'height' is determined as for inline replaced elements.
+
+    // 10.6.2 Inline replaced elements, block-level replaced elements in normal flow, 'inline-block' replaced elements in normal flow and floating replaced elements
+    //
+    // 1. If 'height' and 'width' both have computed values of 'auto' and the element also has an intrinsic height, then that intrinsic height is the used value of 'height'.
+    //
+    // 2. Otherwise, if 'height' has a computed value of 'auto', and the element has an intrinsic ratio then the used value of 'height' is:
+    //    (used width) / (intrinsic ratio)
+    //
+    // 3. Otherwise, if 'height' has a computed value of 'auto', and the element has an intrinsic height, then that intrinsic height is the used value of 'height'.
+    //
+    // 4. Otherwise, if 'height' has a computed value of 'auto', but none of the conditions above are met, then the used value of 'height' must be set to
+    //    the height of the largest rectangle that has a 2:1 ratio, has a height not greater than 150px, and has a width not greater than the device width.
+    auto& style = layoutBox.style();
+    auto width = style.logicalWidth();
+    auto height = style.logicalHeight();
+
+    LayoutUnit computedHeightValue;
+    auto replaced = layoutBox.replaced();
+    ASSERT(replaced);
+
+    if (height.isAuto()) {
+        if (width.isAuto() && replaced->hasIntrinsicHeight()) {
+            // #1
+            computedHeightValue = replaced->intrinsicHeight();
+        } else if (replaced->hasIntrinsicRatio()) {
+            // #2
+            computedHeightValue = width.value() / replaced->intrinsicRatio();
+        } else if (replaced->hasIntrinsicHeight()) {
+            // #3
+            computedHeightValue = replaced->intrinsicHeight();
+        } else {
+            // #4
+            computedHeightValue = 150;
+        }
+    } else
+        computedHeightValue = height.value();
 
     displayBox.setHeight(computedHeightValue);
@@ -264 +313 @@
     }
 
-    displayBox.setWidth(computedWidthValue);   
+    displayBox.setWidth(computedWidthValue);
 }
 
@@ -360 +409 @@
 }
 
+void FormattingContext::computeOutOfFlowReplacedHeight(LayoutContext& layoutContext, const Box& layoutBox, Display::Box& displayBox) const
+{
+    ASSERT(layoutBox.isOutOfFlowPositioned() && layoutBox.replaced());
+    // 10.6.5 Absolutely positioned, replaced elements
+    //
+    // The used value of 'height' is determined as for inline replaced elements.
+    computeReplacedHeight(layoutContext, layoutBox, displayBox);
+}
+
 void FormattingContext::computeOutOfFlowReplacedWidth(LayoutContext& layoutContext, const Box& layoutBox, Display::Box& displayBox) const
 {

trunk/Source/WebCore/layout/FormattingContext.h

@@ -77 +77 @@
 
     virtual void computeOutOfFlowHeight(LayoutContext&, const Box&, Display::Box&) const;
-    virtual void computeFloatingHeight(const Box&, Display::Box&) const;
+    virtual void computeFloatingHeight(LayoutContext&, const Box&, Display::Box&) const;
     virtual void computeInFlowHeight(LayoutContext&, const Box&, Display::Box&) const = 0;
 
@@ -88 +88 @@
     void layoutOutOfFlowDescendants(LayoutContext&s) const;
 
+    void computeReplacedHeight(LayoutContext&, const Box&, Display::Box&) const;
     void computeReplacedWidth(LayoutContext&, const Box&, Display::Box&) const;
 
@@ -93 +94 @@
     void computeOutOfFlowNonReplacedHeight(LayoutContext&, const Box&, Display::Box&) const;
     void computeOutOfFlowNonReplacedWidth(LayoutContext&, const Box&, Display::Box&) const;
+    void computeOutOfFlowReplacedHeight(LayoutContext&, const Box&, Display::Box&) const;
     void computeOutOfFlowReplacedWidth(LayoutContext&, const Box&, Display::Box&) const;
 

trunk/Source/WebCore/layout/blockformatting/BlockFormattingContext.cpp

@@ -190 +190 @@
         return;
     }
-    ASSERT_NOT_IMPLEMENTED_YET();
+    computeReplacedHeight(layoutContext, layoutBox, displayBox);
 }