Adding code to calculate Underline Thickness from Font Metrics, this will be useful when Skia is us…

src/ports/SkFontHost_mac.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 <vector>
 #ifdef SK_BUILD_FOR_MAC
@@ skipping 1361 matching lines @@
     SkPaint::FontMetrics theMetrics;
     theMetrics.fTop          = CGToScalar(-CGRectGetMaxY_inline(theBounds));
     theMetrics.fAscent       = CGToScalar(-CTFontGetAscent(fCTFont));
     theMetrics.fDescent      = CGToScalar( CTFontGetDescent(fCTFont));
     theMetrics.fBottom       = CGToScalar(-CGRectGetMinY_inline(theBounds));
     theMetrics.fLeading      = CGToScalar( CTFontGetLeading(fCTFont));
     theMetrics.fAvgCharWidth = CGToScalar( CGRectGetWidth_inline(theBounds));
     theMetrics.fXMin         = CGToScalar( CGRectGetMinX_inline(theBounds));
     theMetrics.fXMax         = CGToScalar( CGRectGetMaxX_inline(theBounds));
     theMetrics.fXHeight      = CGToScalar( CTFontGetXHeight(fCTFont));
+    theMetrics.fUnderlineThickness = CGToScalar( CTFontGetUnderlineThickness(fCTFont));
+    theMetrics.fUnderlinePosition = CGToScalar( CTFontGetUnderlinePosition(fCTFont));
+
+    if(!theMetrics.fUnderlineThickness)

[bungeman-skia, 2014/02/19 15:39:17]

There is no reason for any of these tests; in this case we must just always set
that we trust these as CoreText only supports fonts which have this information.
Essentially, CoreText is claiming that these values are valid. If it returns a
value of 0, we still need to trust that, as it's perfectly valid to have the
underline position on the baseline.

[h.joshi, 2014/02/19 17:12:03]

Okey, will make changes.

On 2014/02/19 15:39:17, bungeman1 wrote:

+        theMetrics.unsetFontMetricsFlag(SkPaint::FontMetrics::kUnderlineThinknessIsValid_FontMetricFlag);
+    else
+        theMetrics.setFontMetricsFlag(SkPaint::FontMetrics::kUnderlineThinknessIsValid_FontMetricFlag);
+
+    if(!theMetrics.fUnderlinePosition)
+        theMetrics.unsetFontMetricsFlag(SkPaint::FontMetrics::kUnderlinePositionIsValid_FontMetricsflag);
+    else
+        theMetrics.setFontMetricsFlag(SkPaint::FontMetrics::kUnderlinePositionIsValid_FontMetricsflag);
 
     if (mx != NULL) {
         *mx = theMetrics;
     }
     if (my != NULL) {
         *my = theMetrics;
     }
 }
 
 void SkScalerContext_Mac::CTPathElement(void *info, const CGPathElement *element) {
@@ skipping 913 matching lines @@
         return create_typeface(NULL, familyName, (SkTypeface::Style)styleBits);
     }
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 SkFontMgr* SkFontMgr::Factory() {
     return SkNEW(SkFontMgr_Mac);
 }
 #endif