SkScalerContextRec::computeMatrices to return status.

src/core/SkScalerContext.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkScalerContext.h"
 #include "SkAutoPixmapStorage.h"
@@ skipping 669 matching lines @@
 
 void SkScalerContextRec::getSingleMatrix(SkMatrix* m) const {
     this->getLocalMatrix(m);
 
     //  now concat the device matrix
     SkMatrix    deviceMatrix;
     this->getMatrixFrom2x2(&deviceMatrix);
     m->postConcat(deviceMatrix);
 }
 
-void SkScalerContextRec::computeMatrices(PreMatrixScale preMatrixScale, SkVector* s, SkMatrix* sA,
+bool SkScalerContextRec::computeMatrices(PreMatrixScale preMatrixScale, SkVector* s, SkMatrix* sA,
                                          SkMatrix* GsA, SkMatrix* G_inv, SkMatrix* A_out)
 {
     // A is the 'total' matrix.
     SkMatrix A;
     this->getSingleMatrix(&A);
 
     // The caller may find the 'total' matrix useful when dealing directly with EM sizes.
     if (A_out) {
         *A_out = A;
     }
@@ skipping 15 matching lines @@
     {
         s->fX = SK_Scalar1;
         s->fY = SK_Scalar1;
         sA->setScale(0, 0);
         if (GsA) {
             GsA->setScale(0, 0);
         }
         if (G_inv) {
             G_inv->reset();
         }
-        return;
+        return false;
     }
 
     // GA is the matrix A with rotation removed.
     SkMatrix GA;
     bool skewedOrFlipped = A.getSkewX() || A.getSkewY() || A.getScaleX() < 0 || A.getScaleY() < 0;
     if (skewedOrFlipped) {
         // h is where A maps the horizontal baseline.
         SkPoint h = SkPoint::Make(SK_Scalar1, 0);
         A.mapPoints(&h, 1);
 
@@ skipping 59 matching lines @@
         *sA = A;
         sA->preScale(SkScalarInvert(s->fX), SkScalarInvert(s->fY));
     }
 
     // The 'remainingWithoutRotation' matrix GsA is the non-rotational part of A without the scale.
     if (GsA) {
         *GsA = GA;
          // G is rotational so reorders with the scale.
         GsA->preScale(SkScalarInvert(s->fX), SkScalarInvert(s->fY));
     }
+
+    return true;
 }
 
 SkAxisAlignment SkScalerContext::computeAxisAlignmentForHText() {
     // Why fPost2x2 can be used here.
     // getSingleMatrix multiplies in getLocalMatrix, which consists of
     // * fTextSize (a scale, which has no effect)
     // * fPreScaleX (a scale in x, which has no effect)
     // * fPreSkewX (has no effect, but would on vertical text alignment).
     // In other words, making the text bigger, stretching it along the
     // horizontal axis, or fake italicizing it does not move the baseline.
@@ skipping 44 matching lines @@
 SkScalerContext* SkTypeface::createScalerContext(const SkScalerContextEffects& effects,
                                                  const SkDescriptor* desc,
                                                  bool allowFailure) const {
     SkScalerContext* c = this->onCreateScalerContext(effects, desc);
 
     if (!c && !allowFailure) {
         c = new SkScalerContext_Empty(const_cast<SkTypeface*>(this), effects, desc);
     }
     return c;
 }