Issue #1619 - Convert Intrinsic Ratio to Float

https://bugzilla.mozilla.org/show_bug.cgi?id=1547792

Aspect Ratio handling simplified by using floating point integers:
- Multiplication of value (or inverse value) to a known side for Scaling
- No unequal equal values such as "4/3" vs "8/6" vs "20/15"
- Truly "Empty" aspect ratios, even if one dimension is not 0

1 files changed, 10 insertions, 12 deletions

diff --git a/layout/base/nsCSSRendering.h b/layout/base/nsCSSRendering.h
index 791e9656e..8ebeb7537 100644
--- a/layout/base/nsCSSRendering.h
+++ b/layout/base/nsCSSRendering.h
@@ -17,6 +17,7 @@
 #include "nsLayoutUtils.h"
 #include "nsStyleStruct.h"
 #include "nsIFrame.h"
+#include "mozilla/AspectRatio.h"
 
 class gfxDrawable;
 class nsStyleContext;
@@ -41,8 +42,7 @@ class ImageContainer;
 struct CSSSizeOrRatio
 {
   CSSSizeOrRatio()
-    : mRatio(0, 0)
-    , mHasWidth(false)
+    : mHasWidth(false)
     , mHasHeight(false) {}
 
   bool CanComputeConcreteSize() const
@@ -50,12 +50,12 @@ struct CSSSizeOrRatio
     return mHasWidth + mHasHeight + HasRatio() >= 2;
   }
   bool IsConcrete() const { return mHasWidth && mHasHeight; }
-  bool HasRatio() const { return mRatio.width > 0 && mRatio.height > 0; }
+  bool HasRatio() const { return !!mRatio; }
   bool IsEmpty() const
   {
     return (mHasWidth && mWidth <= 0) ||
            (mHasHeight && mHeight <= 0) ||
-           mRatio.width <= 0 || mRatio.height <= 0; 
+           !mRatio; 
   }
 
   // CanComputeConcreteSize must return true when ComputeConcreteSize is
@@ -67,7 +67,7 @@ struct CSSSizeOrRatio
     mWidth = aWidth;
     mHasWidth = true;
     if (mHasHeight) {
-      mRatio = nsSize(mWidth, mHeight);
+      mRatio = AspectRatio::FromSize(mWidth, mHeight);
     }
   }
   void SetHeight(nscoord aHeight)
@@ -75,7 +75,7 @@ struct CSSSizeOrRatio
     mHeight = aHeight;
     mHasHeight = true;
     if (mHasWidth) {
-      mRatio = nsSize(mWidth, mHeight);
+      mRatio = AspectRatio::FromSize(mWidth, mHeight);
     }
   }
   void SetSize(const nsSize& aSize)
@@ -84,16 +84,16 @@ struct CSSSizeOrRatio
     mHeight = aSize.height;
     mHasWidth = true;
     mHasHeight = true;
-    mRatio = aSize;    
+    mRatio = AspectRatio::FromSize(mWidth, mHeight);    
   }
-  void SetRatio(const nsSize& aRatio)
+  void SetRatio(const AspectRatio& aRatio)
   {
     MOZ_ASSERT(!mHasWidth || !mHasHeight,
                "Probably shouldn't be setting a ratio if we have a concrete size");
     mRatio = aRatio;
   }
 
-  nsSize mRatio;
+  AspectRatio mRatio;
   nscoord mWidth;
   nscoord mHeight;
   bool mHasWidth;
@@ -184,11 +184,9 @@ public:
   /**
    * Compute the size of the rendered image using either the 'cover' or
    * 'contain' constraints (aFitType).
-   * aIntrinsicRatio may be an invalid ratio, that is one or both of its
-   * dimensions can be less than or equal to zero.
    */
   static nsSize ComputeConstrainedSize(const nsSize& aConstrainingSize,
-                                       const nsSize& aIntrinsicRatio,
+                                       const mozilla::AspectRatio& aIntrinsicRatio,
                                        FitType aFitType);
   /**
    * Compute the size of the rendered image (the concrete size) where no cover/