Add nine patch type to SkRRect.

src/core/SkRRect.cpp

Index: src/core/SkRRect.cpp
diff --git a/src/core/SkRRect.cpp b/src/core/SkRRect.cpp
index 915ed75327f590c567ec18a5e9e0d92f64b76ee4..03f173eafe60164c4539d08882d9f00be8603161 100644
--- a/src/core/SkRRect.cpp
+++ b/src/core/SkRRect.cpp
@@ -43,6 +43,55 @@ void SkRRect::setRectXY(const SkRect& rect, SkScalar xRad, SkScalar yRad) {
     SkDEBUGCODE(this->validate();)
 }
 
+void SkRRect::setNinePatch(const SkRect& rect, SkScalar leftRad, SkScalar topRad,
+                           SkScalar rightRad, SkScalar bottomRad) {
+    if (rect.isEmpty()) {
+        this->setEmpty();
+        return;
+    }
+
+    leftRad = SkMaxScalar(leftRad, 0);
+    topRad = SkMaxScalar(topRad, 0);
+    rightRad = SkMaxScalar(rightRad, 0);
+    bottomRad = SkMaxScalar(bottomRad, 0);
+

[robertphillips, 2014/03/14 16:22:59]

I think we need to scale the x & y radii separately?

[bsalomon, 2014/03/14 16:30:20]

We don't in the other setters (which I just stole from).

[robertphillips, 2014/03/14 16:52:07]

Sigh - that is correct
(http://www.w3.org/TR/2010/WD-css3-background-20100612/#the-border-radius --
Overlapping Curves).

+    SkScalar scale = SK_Scalar1;
+    if (leftRad + rightRad > rect.width()) {
+        scale = SkScalarDiv(rect.width(), leftRad + rightRad);
+    }
+    if (topRad + bottomRad > rect.height()) {
+        scale = SkMinScalar(scale, SkScalarDiv(rect.width(), leftRad + rightRad));
+    }
+
+    if (scale < SK_Scalar1) {
+        leftRad = SkScalarMul(leftRad, scale);
+        topRad = SkScalarMul(topRad, scale);
+        rightRad = SkScalarMul(rightRad, scale);
+        bottomRad = SkScalarMul(bottomRad, scale);
+    }
+
+    if (leftRad == rightRad && topRad == bottomRad) {
+        if (leftRad >= SkScalarHalf(rect.width()) && topRad >= SkScalarHalf(rect.height())) {
+            fType = kOval_Type;

[robertphillips, 2014/03/14 16:22:59]

don't we also need "&& 0 == topRad"?

[bsalomon, 2014/03/14 16:30:20]

I don't think so... if the top radius is 0 then so is the bottom, which means
all the corners are square, right?

Maybe I should be jamming the them to 0 here so we store them that way?

[robertphillips, 2014/03/14 16:52:07]

You're right - probably both a comment and jamming them all to zero is in order

+        } else if (0 == leftRad) {
+            fType = kRect_Type;
+        } else {
+            fType = kSimple_Type;
+        }
+    } else {
+        fType = kNinePatch_Type;
+    }
+
+    fRect = rect;
+    fRadii[kUpperLeft_Corner].set(leftRad, topRad);
+    fRadii[kUpperRight_Corner].set(rightRad, topRad);
+    fRadii[kLowerRight_Corner].set(rightRad, bottomRad);
+    fRadii[kLowerLeft_Corner].set(leftRad, bottomRad);
+
+    SkDEBUGCODE(this->validate();)
+}
+
+
 void SkRRect::setRectRadii(const SkRect& rect, const SkVector radii[4]) {
     if (rect.isEmpty()) {
         this->setEmpty();
@@ -238,7 +287,14 @@ void SkRRect::computeType() const {
         return;
     }
 
-    fType = kComplex_Type;
+    if (fRadii[kUpperLeft_Corner].fX == fRadii[kLowerLeft_Corner].fX &&
+        fRadii[kUpperLeft_Corner].fY == fRadii[kUpperRight_Corner].fY &&
+        fRadii[kUpperRight_Corner].fX == fRadii[kLowerRight_Corner].fX &&
+        fRadii[kLowerLeft_Corner].fY == fRadii[kLowerRight_Corner].fY) {
+        fType = kNinePatch_Type;
+    } else {
+        fType = kComplex_Type;
+    }
 }
 
 static bool matrix_only_scale_and_translate(const SkMatrix& matrix) {
@@ -391,6 +447,10 @@ void SkRRect::validate() const {
             allCornersSquare = false;
         }
     }

[robertphillips, 2014/03/14 16:22:59]

maybe a radii_make_nine_patch predicate to share code with above?

[bsalomon, 2014/03/14 16:30:20]

I'm not sure what you mean.

[robertphillips, 2014/03/14 16:52:07]

Add a helper function?

[bsalomon, 2014/03/14 17:15:31]

gotcha! will do. I thought you meant incorporating into the above loop.

+    bool patchesOfNine = fRadii[kUpperLeft_Corner].fX == fRadii[kLowerLeft_Corner].fX &&
+                         fRadii[kUpperLeft_Corner].fY == fRadii[kUpperRight_Corner].fY &&
+                         fRadii[kUpperRight_Corner].fX == fRadii[kLowerRight_Corner].fX &&
+                         fRadii[kLowerLeft_Corner].fY == fRadii[kLowerRight_Corner].fY;
 
     switch (fType) {
         case kEmpty_Type:
@@ -417,9 +477,15 @@ void SkRRect::validate() const {
             SkASSERT(!fRect.isEmpty());
             SkASSERT(!allRadiiZero && allRadiiSame && !allCornersSquare);
             break;
+        case kNinePatch_Type:
+            SkASSERT(!fRect.isEmpty());
+            SkASSERT(!allRadiiZero && !allRadiiSame && !allCornersSquare);
+            SkASSERT(patchesOfNine);
+            break;
         case kComplex_Type:
             SkASSERT(!fRect.isEmpty());
             SkASSERT(!allRadiiZero && !allRadiiSame && !allCornersSquare);
+            SkASSERT(!patchesOfNine);
             break;
         case kUnknown_Type:
             // no limits on this