Bug 841192. Part 12: Move RoundedRectIntersectsRect from nsDisplayList.cpp to nsLayoutUtils. r=mattwoodrow

--HG--
extra : rebase_source : aa0ad96c363b70895b068a6d4805f9164cc03b27

layout/base/nsDisplayList.cpp

@@ -1657,69 +1657,6 @@ nsDisplayBackgroundImage::AppendBackgroundItemsToTop(nsDisplayListBuilder* aBuil
   return NS_OK;
 }
 
-// Helper for RoundedRectIntersectsRect.
-static bool
-CheckCorner(nscoord aXOffset, nscoord aYOffset,
-            nscoord aXRadius, nscoord aYRadius)
-{
-  NS_ABORT_IF_FALSE(aXOffset > 0 && aYOffset > 0,
-                    "must not pass nonpositives to CheckCorner");
-  NS_ABORT_IF_FALSE(aXRadius >= 0 && aYRadius >= 0,
-                    "must not pass negatives to CheckCorner");
-
-  // Avoid floating point math unless we're either (1) within the
-  // quarter-ellipse area at the rounded corner or (2) outside the
-  // rounding.
-  if (aXOffset >= aXRadius || aYOffset >= aYRadius)
-    return true;
-
-  // Convert coordinates to a unit circle with (0,0) as the center of
-  // curvature, and see if we're inside the circle or outside.
-  float scaledX = float(aXRadius - aXOffset) / float(aXRadius);
-  float scaledY = float(aYRadius - aYOffset) / float(aYRadius);
-  return scaledX * scaledX + scaledY * scaledY < 1.0f;
-}
-
-
-/**
- * Return whether any part of aTestRect is inside of the rounded
- * rectangle formed by aBounds and aRadii (which are indexed by the
- * NS_CORNER_* constants in nsStyleConsts.h).
- *
- * See also RoundedRectContainsRect.
- */
-static bool
-RoundedRectIntersectsRect(const nsRect& aRoundedRect, nscoord aRadii[8],
-                          const nsRect& aTestRect)
-{
-  NS_ABORT_IF_FALSE(aTestRect.Intersects(aRoundedRect),
-                    "we should already have tested basic rect intersection");
-
-  // distances from this edge of aRoundedRect to opposite edge of aTestRect,
-  // which we know are positive due to the Intersects check above.
-  nsMargin insets;
-  insets.top = aTestRect.YMost() - aRoundedRect.y;
-  insets.right = aRoundedRect.XMost() - aTestRect.x;
-  insets.bottom = aRoundedRect.YMost() - aTestRect.y;
-  insets.left = aTestRect.XMost() - aRoundedRect.x;
-
-  // Check whether the bottom-right corner of aTestRect is inside the
-  // top left corner of aBounds when rounded by aRadii, etc.  If any
-  // corner is not, then fail; otherwise succeed.
-  return CheckCorner(insets.left, insets.top,
-                     aRadii[NS_CORNER_TOP_LEFT_X],
-                     aRadii[NS_CORNER_TOP_LEFT_Y]) &&
-         CheckCorner(insets.right, insets.top,
-                     aRadii[NS_CORNER_TOP_RIGHT_X],
-                     aRadii[NS_CORNER_TOP_RIGHT_Y]) &&
-         CheckCorner(insets.right, insets.bottom,
-                     aRadii[NS_CORNER_BOTTOM_RIGHT_X],
-                     aRadii[NS_CORNER_BOTTOM_RIGHT_Y]) &&
-         CheckCorner(insets.left, insets.bottom,
-                     aRadii[NS_CORNER_BOTTOM_LEFT_X],
-                     aRadii[NS_CORNER_BOTTOM_LEFT_Y]);
-}
-
 // Check that the rounded border of aFrame, added to aToReferenceFrame,
 // intersects aRect.  Assumes that the unrounded border has already
 // been checked for intersection.

layout/base/nsLayoutUtils.cpp

@@ -1425,6 +1425,62 @@ nsLayoutUtils::RoundedRectIntersectRect(const nsRect& aRoundedRect,
   return result;
 }
 
+// Helper for RoundedRectIntersectsRect.
+static bool
+CheckCorner(nscoord aXOffset, nscoord aYOffset,
+            nscoord aXRadius, nscoord aYRadius)
+{
+  NS_ABORT_IF_FALSE(aXOffset > 0 && aYOffset > 0,
+                    "must not pass nonpositives to CheckCorner");
+  NS_ABORT_IF_FALSE(aXRadius >= 0 && aYRadius >= 0,
+                    "must not pass negatives to CheckCorner");
+
+  // Avoid floating point math unless we're either (1) within the
+  // quarter-ellipse area at the rounded corner or (2) outside the
+  // rounding.
+  if (aXOffset >= aXRadius || aYOffset >= aYRadius)
+    return true;
+
+  // Convert coordinates to a unit circle with (0,0) as the center of
+  // curvature, and see if we're inside the circle or outside.
+  float scaledX = float(aXRadius - aXOffset) / float(aXRadius);
+  float scaledY = float(aYRadius - aYOffset) / float(aYRadius);
+  return scaledX * scaledX + scaledY * scaledY < 1.0f;
+}
+
+bool
+nsLayoutUtils::RoundedRectIntersectsRect(const nsRect& aRoundedRect,
+                                         const nscoord aRadii[8],
+                                         const nsRect& aTestRect)
+{
+  if (!aTestRect.Intersects(aRoundedRect))
+    return false;
+
+  // distances from this edge of aRoundedRect to opposite edge of aTestRect,
+  // which we know are positive due to the Intersects check above.
+  nsMargin insets;
+  insets.top = aTestRect.YMost() - aRoundedRect.y;
+  insets.right = aRoundedRect.XMost() - aTestRect.x;
+  insets.bottom = aRoundedRect.YMost() - aTestRect.y;
+  insets.left = aTestRect.XMost() - aRoundedRect.x;
+
+  // Check whether the bottom-right corner of aTestRect is inside the
+  // top left corner of aBounds when rounded by aRadii, etc.  If any
+  // corner is not, then fail; otherwise succeed.
+  return CheckCorner(insets.left, insets.top,
+                     aRadii[NS_CORNER_TOP_LEFT_X],
+                     aRadii[NS_CORNER_TOP_LEFT_Y]) &&
+         CheckCorner(insets.right, insets.top,
+                     aRadii[NS_CORNER_TOP_RIGHT_X],
+                     aRadii[NS_CORNER_TOP_RIGHT_Y]) &&
+         CheckCorner(insets.right, insets.bottom,
+                     aRadii[NS_CORNER_BOTTOM_RIGHT_X],
+                     aRadii[NS_CORNER_BOTTOM_RIGHT_Y]) &&
+         CheckCorner(insets.left, insets.bottom,
+                     aRadii[NS_CORNER_BOTTOM_LEFT_X],
+                     aRadii[NS_CORNER_BOTTOM_LEFT_Y]);
+}
+
 nsRect
 nsLayoutUtils::MatrixTransformRectOut(const nsRect &aBounds,
                                       const gfx3DMatrix &aMatrix, float aFactor)

layout/base/nsLayoutUtils.h

@@ -657,6 +657,15 @@ public:
                                            const nscoord aRadii[8],
                                            const nsRect& aContainedRect);
 
+  /**
+   * Return whether any part of aTestRect is inside of the rounded
+   * rectangle formed by aBounds and aRadii (which are indexed by the
+   * NS_CORNER_* constants in nsStyleConsts.h). This is precise.
+   */
+  static bool RoundedRectIntersectsRect(const nsRect& aRoundedRect,
+                                        const nscoord aRadii[8],
+                                        const nsRect& aTestRect);
+
   enum {
     PAINT_IN_TRANSFORM = 0x01,
     PAINT_SYNC_DECODE_IMAGES = 0x02,