commit 9abc6041877077beb864314306884392d19b82f5
author Cary Clark <cary@android.com> Mon Mar 01 13:38:55 2010 -0500
committer Cary Clark <cary@android.com> Mon Mar 01 14:09:39 2010 -0500
tree 2ea25acc3fcb1e0a0811ed68a71e35ce0d29064d
parent bd176981556f55a8f081b8ee6c804a384deb9644

use advance widths to deduce spaces in selected text

The earlier method of using bounding boxes does not work if the
characters have sufficiently large kerning, such as 'A Java' or
sufficiently small kerning, such as '16'.

Also, don't add spaces after hyphens or dashes, and detect
baseline changes correctly. Reset the first space condition once
text is clipped out.

http://b/2457350
http://b/2165553

WebKit/android/nav/SelectText.cpp

diff --git a/WebKit/android/nav/SelectText.cpp b/WebKit/android/nav/SelectText.cpp
index f028a0f..e471307 100644
--- a/WebKit/android/nav/SelectText.cpp
+++ b/WebKit/android/nav/SelectText.cpp
@@ -193,6 +193,10 @@
     bool mCapture;
 };
 
+#define HYPHEN_MINUS 0x2D // ASCII hyphen
+#define HYPHEN 0x2010 // unicode hyphen, first in range of dashes
+#define HORZ_BAR 0x2015 // unicode horizontal bar, last in range of dashes
+
 class TextExtractor : public CommonCheck {
 public:
     TextExtractor(const SkRegion& region) : mSelectRegion(region),
@@ -204,38 +208,58 @@
         INHERITED::setUp(paint, matrix, y, text);
         SkPaint charPaint = paint;
         charPaint.setTextEncoding(SkPaint::kUTF8_TextEncoding);
-        mMinSpaceWidth = charPaint.measureText(" ", 1) * 3 / 4;
+        mMinSpaceWidth = std::max(0, SkScalarToFixed(
+            charPaint.measureText(" ", 1)) - SK_Fixed1);
     }
 
-    virtual bool onIRect(const SkIRect& rect, uint16_t glyphID) {
+    virtual bool onIRectGlyph(const SkIRect& rect,
+        const SkBounder::GlyphRec& rec)
+    {
         SkIRect full;
         full.set(rect.fLeft, top(), rect.fRight, bottom());
         if (mSelectRegion.contains(full)) {
-            if (!mSkipFirstSpace
-                    && ((mLast.fTop < top() && mLast.fBottom < top() + 2)
-                    || (mLast.fLeft < rect.fLeft // glyphs are LTR
-                    && mLast.fRight + mMinSpaceWidth < rect.fLeft))) {
-                DBG_NAV_LOGD("TextExtractor [%02x] append space", glyphID);
+            if (!mSkipFirstSpace && (mLastUni < HYPHEN || mLastUni > HORZ_BAR)
+                    && mLastUni != HYPHEN_MINUS
+                    && (mLastGlyph.fLSB.fY != rec.fLSB.fY // new baseline
+                    || mLastGlyph.fLSB.fX > rec.fLSB.fX // glyphs are LTR
+                    || mLastGlyph.fRSB.fX + mMinSpaceWidth < rec.fLSB.fX)) {
+                DBG_NAV_LOGD("TextExtractor append space"
+                    " mLast=(%d,%d,r=%d,b=%d) mLastGlyph=((%g,%g),(%g,%g),%d)"
+                    " full=(%d,%d,r=%d,b=%d) rec=((%g,%g),(%g,%g),%d)"
+                    " mMinSpaceWidth=%g",
+                    mLast.fLeft, mLast.fTop, mLast.fRight, mLast.fBottom,
+                    SkFixedToScalar(mLastGlyph.fLSB.fX),
+                    SkFixedToScalar(mLastGlyph.fLSB.fY),
+                    SkFixedToScalar(mLastGlyph.fRSB.fX),
+                    SkFixedToScalar(mLastGlyph.fRSB.fY), mLastGlyph.fGlyphID,
+                    full.fLeft, full.fTop, full.fRight, full.fBottom,
+                    SkFixedToScalar(rec.fLSB.fX),
+                    SkFixedToScalar(rec.fLSB.fY),
+                    SkFixedToScalar(rec.fRSB.fX),
+                    SkFixedToScalar(rec.fRSB.fY), rec.fGlyphID,
+                    SkFixedToScalar(mMinSpaceWidth));
                 *mSelectText.append() = ' ';
             } else
                 mSkipFirstSpace = false;
             DBG_NAV_LOGD("TextExtractor [%02x] append full=(%d,%d,r=%d,b=%d)",
-                glyphID, full.fLeft, full.fTop, full.fRight, full.fBottom);
-            SkUnichar uni;
+                rec.fGlyphID, full.fLeft, full.fTop, full.fRight, full.fBottom);
             SkPaint utfPaint = *mPaint;
             utfPaint.setTextEncoding(SkPaint::kUTF16_TextEncoding);
-            utfPaint.glyphsToUnichars(&glyphID, 1, &uni);
-            if (uni) {
+            utfPaint.glyphsToUnichars(&rec.fGlyphID, 1, &mLastUni);
+            if (mLastUni) {
                 uint16_t chars[2];
-                size_t count = SkUTF16_FromUnichar(uni, chars);
+                size_t count = SkUTF16_FromUnichar(mLastUni, chars);
                 *mSelectText.append() = chars[0];
                 if (count == 2)
                     *mSelectText.append() = chars[1];
             }
             mLast = full;
-        } else
+            mLastGlyph = rec;
+        } else {
+            mSkipFirstSpace = true;
             DBG_NAV_LOGD("TextExtractor [%02x] skip full=(%d,%d,r=%d,b=%d)",
-                glyphID, full.fLeft, full.fTop, full.fRight, full.fBottom);
+                rec.fGlyphID, full.fLeft, full.fTop, full.fRight, full.fBottom);
+        }
         return false;
     }
 
@@ -247,7 +271,9 @@
     const SkRegion& mSelectRegion;
     SkTDArray<uint16_t> mSelectText;
     SkIRect mLast;
-    SkScalar mMinSpaceWidth;
+    SkBounder::GlyphRec mLastGlyph;
+    SkUnichar mLastUni;
+    SkFixed mMinSpaceWidth;
     bool mSkipFirstSpace;
 private:
     typedef CommonCheck INHERITED;