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

src/core/SkPaint.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 "SkPaint.h"
 #include "SkAnnotation.h"
@@ skipping 30 matching lines @@
 //#define SK_REPORT_API_RANGE_CHECK
 
 #ifdef SK_BUILD_FOR_ANDROID
 #define GEN_ID_INC                  fGenerationID++
 #define GEN_ID_INC_EVAL(expression) if (expression) { fGenerationID++; }
 #else
 #define GEN_ID_INC
 #define GEN_ID_INC_EVAL(expression)
 #endif
 
+#define setFontMetricsBitSet(__fObject, __bitSet)       \
+{                                                                                        \
+    if(__fObject != NULL) {                                                \
+        __fObject->fFontMetricsFlag |= __bitSet;             \
+    }                                                                                     \
+}
+
 SkPaint::SkPaint() {
     // since we may have padding, we zero everything so that our memcmp() call
     // in operator== will work correctly.
     // with this, we can skip 0 and null individual initializations
     sk_bzero(this, sizeof(*this));
 
 #if 0   // not needed with the bzero call above
     fTypeface   = NULL;
     fTextSkewX  = 0;
     fPathEffect  = NULL;
@@ skipping 1217 matching lines @@
         zoomMatrix.setScale(zoom, zoom);
         zoomPtr = &zoomMatrix;
     }
 
     FontMetrics storage;
     if (NULL == metrics) {
         metrics = &storage;
     }
 
     paint.descriptorProc(NULL, zoomPtr, FontMetricsDescProc, metrics, true);
+    metrics->fFontMetricsFlag = 0;
 
     if (scale) {
-        metrics->fTop = SkScalarMul(metrics->fTop, scale);
-        metrics->fAscent = SkScalarMul(metrics->fAscent, scale);
-        metrics->fDescent = SkScalarMul(metrics->fDescent, scale);
-        metrics->fBottom = SkScalarMul(metrics->fBottom, scale);
-        metrics->fLeading = SkScalarMul(metrics->fLeading, scale);
-        metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale);
-        metrics->fXMin = SkScalarMul(metrics->fXMin, scale);
-        metrics->fXMax = SkScalarMul(metrics->fXMax, scale);
-        metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale);
+        if( (metrics->fTop = SkScalarMul(metrics->fTop, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_Top); };
+        if( (metrics->fAscent = SkScalarMul(metrics->fAscent, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_Ascent); };
+        if( (metrics->fDescent = SkScalarMul(metrics->fDescent, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_Descent); };
+        if( (metrics->fBottom = SkScalarMul(metrics->fBottom, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_Bottom); };
+        if( (metrics->fLeading = SkScalarMul(metrics->fLeading, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_Leading); };
+        if( (metrics->fAvgCharWidth = SkScalarMul(metrics->fAvgCharWidth, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_AvgCharWidth); };
+        if( (metrics->fXMin = SkScalarMul(metrics->fXMin, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_XMin); };
+        if( (metrics->fXMax = SkScalarMul(metrics->fXMax, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_XMax); };
+        if( (metrics->fXHeight = SkScalarMul(metrics->fXHeight, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_XHeight); };
+        if( (metrics->fUnderlineThickness = SkScalarMul(metrics->fUnderlineThickness, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_UnderlineThickness); };
+        if( (metrics->fUnderlinePosition = SkScalarMul(metrics->fUnderlinePosition, scale)) ) { setFontMetricsBitSet(metrics, kFontMetrics_UnderlinePosition); };
     }
     return metrics->fDescent - metrics->fAscent + metrics->fLeading;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 
 static void set_bounds(const SkGlyph& g, SkRect* bounds, SkScalar scale) {
     bounds->set(g.fLeft * scale,
                 g.fTop * scale,
                 (g.fLeft + g.fWidth) * scale,
@@ skipping 941 matching lines @@
         this->getMaskFilter()->computeFastBounds(*storage, storage);
     }
 
     if (this->getImageFilter()) {
         this->getImageFilter()->computeFastBounds(*storage, storage);
     }
 
     return *storage;
 }
 
+bool SkPaint::isFontMetricsBitSet(FontMetrics * fObject, FontMetricsBitSet bitSet) const
+{
+    if(fObject != NULL) {
+        return SkToBool(fObject->fFontMetricsFlag & bitSet);
+    }
+    return false;
+}
+
 #ifdef SK_DEVELOPER
 void SkPaint::toString(SkString* str) const {
     str->append("<dl><dt>SkPaint:</dt><dd><dl>");
 
     SkTypeface* typeface = this->getTypeface();
     if (NULL != typeface) {
         SkDynamicMemoryWStream ostream;
         typeface->serialize(&ostream);
         SkAutoTUnref<SkData> data(ostream.copyToData());
 
@@ skipping 273 matching lines @@
             case SkXfermode::kPlus_Mode:
                 return 0 == this->getAlpha();
             case SkXfermode::kDst_Mode:
                 return true;
             default:
                 break;
         }
     }
     return false;
 }