vcl: add GenericSalLayout::GetTextRect()

I have extended GlyphItem to also record the original and new height,
along with the y offset.

Change-Id: I1e9646a8f0d844951d5533d035d9a16dbc8e257c
Reviewed-on: https://gerrit.libreoffice.org/14216Reviewed-by: Chris Sherlock <chris.sherlock79@gmail.com>
Tested-by: Chris Sherlock <chris.sherlock79@gmail.com>

vcl/generic/glyphs/gcach_layout.cxx

@@ -514,7 +514,7 @@ bool HbLayoutEngine::Layout(ServerFontLayout& rLayout, ImplLayoutArgs& rArgs)
                 int32_t nYAdvance = pHbPositions[i].y_advance >> 6;
 
                 Point aNewPos = Point(aCurrPos.X() + nXOffset, -(aCurrPos.Y() + nYOffset));
-                const GlyphItem aGI(nCharPos, nGlyphIndex, aNewPos, nGlyphFlags, nXAdvance, nXOffset);
+                const GlyphItem aGI(nCharPos, nGlyphIndex, aNewPos, nGlyphFlags, nXAdvance, nXOffset, nYAdvance, nYOffset);
                 rLayout.AppendGlyph(aGI);
 
                 aCurrPos.X() += nXAdvance;

vcl/inc/sallayout.hxx

@@ -273,9 +273,15 @@ struct GlyphItem
 {
     int     mnFlags;
     int     mnCharPos;      // index in string
+
     int     mnOrigWidth;    // original glyph width
     int     mnNewWidth;     // width after adjustments
     int     mnXOffset;
+
+    int     mnOrigHeight;    // original glyph height
+    int     mnNewHeight;     // width after adjustments
+    int     mnYOffset;
+
     sal_GlyphId maGlyphId;
     Point   maLinearPos;    // absolute position of non rotated string
 
@@ -298,10 +304,12 @@ public:
             {}
 
             GlyphItem( int nCharPos, sal_GlyphId aGlyphId, const Point& rLinearPos,
-                long nFlags, int nOrigWidth, int nXOffset )
+                long nFlags, int nOrigWidth, int nXOffset, int nOrigHeight, int nYOffset )
             :   mnFlags(nFlags), mnCharPos(nCharPos),
                 mnOrigWidth(nOrigWidth), mnNewWidth(nOrigWidth),
                 mnXOffset(nXOffset),
+                mnOrigHeight(nOrigHeight), mnNewHeight(nOrigHeight),
+                mnYOffset(nYOffset),
                 maGlyphId(aGlyphId), maLinearPos(rLinearPos)
             {}
 
@@ -330,6 +338,7 @@ public:
 
     // used by upper layers
     virtual DeviceCoordinate GetTextWidth() const SAL_OVERRIDE;
+    virtual Rectangle GetTextRect() const;
     virtual DeviceCoordinate FillDXArray( DeviceCoordinate* pDXArray ) const SAL_OVERRIDE;
     virtual sal_Int32 GetTextBreak(DeviceCoordinate nMaxWidth, DeviceCoordinate nCharExtra, int nFactor) const SAL_OVERRIDE;
     virtual void    GetCaretPositions( int nArraySize, long* pCaretXArray ) const SAL_OVERRIDE;

vcl/source/gdi/sallayout.cxx

@@ -945,6 +945,43 @@ DeviceCoordinate GenericSalLayout::GetTextWidth() const
     return nWidth;
 }
 
+Rectangle GenericSalLayout::GetTextRect() const
+{
+    if( m_GlyphItems.empty() )
+        return Rectangle(Point(0, 0), Size(0, 0));
+
+    // initialize the extent
+    DeviceCoordinate nMinXPos = 0;
+    DeviceCoordinate nMaxXPos = 0;
+
+    DeviceCoordinate nMinYPos = 0;
+    DeviceCoordinate nMaxYPos = 0;
+
+    for( GlyphVector::const_iterator pGlyphIter = m_GlyphItems.begin(), end = m_GlyphItems.end(); pGlyphIter != end ; ++pGlyphIter )
+    {
+        // update the text extent with the glyph extent
+        DeviceCoordinate nXPos = pGlyphIter->maLinearPos.X();
+        DeviceCoordinate nYPos = pGlyphIter->maLinearPos.Y();
+
+        if( nMinXPos > nXPos )
+            nMinXPos = nXPos;
+        nXPos += pGlyphIter->mnNewWidth - pGlyphIter->mnXOffset;
+        if( nMaxXPos < nXPos )
+            nMaxXPos = nXPos;
+
+        if( nMinYPos > nYPos )
+            nMinYPos = nYPos;
+        nYPos += pGlyphIter->mnNewWidth - pGlyphIter->mnYOffset;
+        if( nMaxYPos < nYPos )
+            nMaxYPos = nYPos;
+    }
+
+    DeviceCoordinate nWidth  = nMaxXPos - nMinXPos;
+    DeviceCoordinate nHeight = nMaxYPos - nMinYPos;
+
+    return Rectangle( Point(nMinXPos, nMinYPos), Size(nWidth, nHeight) );
+}
+
 void GenericSalLayout::AdjustLayout( ImplLayoutArgs& rArgs )
 {
     SalLayout::AdjustLayout( rArgs );